You asked, we’re answering: Your top questions about Covid-19 and vaccines

In August, the US Centers for Disease Control and Prevention eliminated several recommendations for schools while continuing to emphasize other key Covid-19 precautions.

Under the new guidelines, the CDC no longer recommends:

• Staying in the same classroom to avoid mixing with other classrooms — a practice known as cohorting.
• The so-called “test-to-stay” strategy, in which students who were exposed to someone with Covid-19 needed to regularly test negative to stay in the classroom.

But the CDC said other precautions are still important. For example:

• Everyone should wear a high-quality mask indoors if they’re in part of the country where the Covid-19 community level is high. Community levels are determined base on local cases, hospitalization rates and hospital capacity. According to the CDC, about 40% of US counties had a high Covid-19 community level as of August 11.
• “People who have known or suspected exposure to COVID-19 should also wear a well-fitting mask or respirator around others for 10 days from their last exposure, regardless of vaccination status or history of prior infection,” the CDC’s website states.
• People who test positive should stay home for at least 5 days and wear a mask around others for at least 10 days.

White House Covid-19 Response Coordinator Dr. Ashish Jha said he anticipates “a very different school year” this year.

“We should look forward to a school year where every child is in school in-person, full-time for the whole year,” Jha said, stressing the importance of vaccination for children and teachers. “I think we have all the ability to do that.”

Updated boosters that will help the immune system fight Omicron subvariants BA.4 and BA.5 will likely be available in early to mid-September, White House Covid-19 Response Coordinator Dr. Ashish Jha said August 16.

“These are substantial upgrades in our vaccines in terms of their ability to prevent infection to prevent transmission,” Jha said.

As of August 13, the highly contagious BA.4 and BA.5 strains made up the vast majority of new Covid-19 cases, according to estimates from the US Centers for Disease Control and Prevention.

Both Pfizer and Moderna have been working on bivalent boosters — vaccines that include both the original formula and a new one that targets the Omicron BA.4 and BA.5 subvariants.

If the shots meet US Food and Drug Administration standards, they will probably be available as early as September, the FDA said.

The United Kingdom has already approved Moderna’s bivalent booster for adults “after it was found to meet the UK regulator’s standards of safety, quality and effectiveness,” the UK government said in a statement August 15.

Anyone age 5 and up who got a 2nd dose of the Pfizer/BioNTech vaccine at least 5 months ago can now get a booster shot (or 3rd dose) of vaccine.

The US Food and Drug Administration issued a statement saying 2nd doses of the vaccine eventually wane. The FDA said 3rd doses boosted antibody levels.

Even though Covid-19 tends to be less severe among children, “the omicron wave has seen more kids getting sick with the disease and being hospitalized, and children may also experience longer term effects, even following initially mild disease,” FDA Commissioner Dr. Robert M. Califf said in a written statement.

“Vaccination continues to be the most effective way to prevent COVID-19 and its severe consequences, and it is safe,” Califf said. “If your child is eligible for the Pfizer-BioNTech COVID-19 Vaccine and has not yet received their primary series, getting them vaccinated can help protect them from the potentially severe consequences that can occur, such as hospitalization and death.”

The recommended gap between 2nd doses and booster doses of the Pfizer vaccine has been shortened – from 6 months to 5 months, the US Centers for Disease Control and Prevention announced in January.

Those who got the 2-dose Moderna vaccine should get a booster shot 6 months after the second dose, the CDC said.

And those who got the single-dose Johnson & Johnson vaccine should get a booster shot after 2 months.

For booster shots, you don’t have to get the same brand of vaccine that you got for your initial vaccination. The FDA has said it’s OK to mix and match brands for the booster dose.

Some immunocompromised people ages 12 and older and all adults ages 50 and up can now get a 4th dose of the Pfizer/BioNTech or Moderna vaccines.

Kids as young as 6 months old can now start getting pediatric doses of the Pfizer/BioNTech vaccine or Moderna vaccine.

Parents can keep track of vaccine availability at vaccines.gov.

The dosages of the vaccines for younger children are a fraction of the dosages for older children and adults.

For kids as young as 6 months old, the US Food and Drug Administration has authorized 3 doses of the Pfizer vaccine or 2 doses of the Moderna vaccine.

With the Pfizer/BioNTech vaccine, the US Centers for Disease Control and Prevention said kids ages 6 months through 4 years should get 3 doses at the following intervals:

• Between the 1st and 2nd doses: 3 to 8 weeks
• Between the 2nd and 3rd doses: At least 8 weeks
• Those with moderately or severely weakened immune systems should separate the 1st and 2nd doses by 3 weeks and the 2nd and 3rd doses by at least 8 weeks, the CDC said.

With the Moderna vaccine, the CDC said children ages 6 months through 5 years should get their doses at the following intervals:

• Between the 1st and 2nd dose: 4 to 8 weeks
• The CDC said children in this age group who are moderately or severely immunocompromised can get a 3rd dose of the Moderna vaccine. For these children, the 1st and 2nd doses should be separated by 4 weeks, and the 2nd and 3rd doses should be separated by at least 4 weeks.

With the BA.5 variant sweeping the country — particularly among young adults — health officials have been considering 2nd booster shots for healthy adults under 50.

But not even the head of the National Institute of Allergy and Infectious Diseases knows when additional doses might be authorized for all younger adults.

“Hopefully we’ll get an answer reasonably soon,” Dr. Anthony Fauci told CNN on July 16.

Right now, anyone age 50 and up can get a 2nd booster shot. For those who got the Pfizer or Moderna vaccines, that typically means a 4th overall dose.

Some people under age 50 can also get a 2nd booster shot — for example, those who are moderately or severely immunocompromised. These people are at greater risk of severe illness and death if they get Covid-19, the US Centers for Disease Control and Prevention says.

According to the CDC, you can be moderately or severely immunocompromised if you:

• Have been receiving active cancer treatment for tumors or cancers of the blood
• Received an organ transplant and are taking medicine to suppress the immune system
• Received chimeric antigen receptor (CAR)-T-cell therapy (a treatment to help your immune system attach to and kill cancer cells) or received a stem cell transplant within the last 2 years
• Have moderate or severe primary immunodeficiency (such as DiGeorge syndrome or Wiskott-Aldrich syndrome)
• Have advanced or untreated HIV infection
• Are getting treatment with high-dose corticosteroids or other drugs that might suppress their immune response

BA.5 is an offshoot of the Omicron variant that’s now the dominant strain in the US, according to the Centers for Disease Control and Prevention.

Like previously dominant strains, BA.5 has mutations that have allowed it to spread easily and quickly overtake other variants. Specifically, BA.5 has three mutations in its spike protein that make it better at infecting cells and better at slipping past immune defenses.

“But we do know it to be more transmissible and more immune-evading,” Walensky said. “People with prior infection, even with BA.1 and BA.2, are likely still at risk for BA.4 or BA.5,” CDC Director Dr. Rochelle Walensky said.

The reason at-home antigen tests expire is because Covid-19 test components “may degrade, or break down, over time,” the US Food and Drug Administration says.

“Because of this, expired test kits could give inaccurate test results.”

But the expiration dates for some at-home Covid-19 tests have been extended. That’s because when at-home antigen tests first hit the market, manufacturers only had several months of data as to how long the tests would work effectively.

“When the tests were first given the green light, when they were approved by the Food and Drug Administration, one of the things that the FDA asked the test developers to do is say, ‘OK, if I have the test at home and I have them on the shelf or on my bookshelf, for how long will they still be accurate?’” said Dr. William Schaffner, a professor of infectious diseases at Vanderbilt University Medical Center.

“Of course, in the beginning when the tests were first developed, the manufacturers waited let’s say 3 months or 6 months, and then they went to the Food and Drug Administration and said, ‘Here is the data,’” Schaffner said.

“Once the test manufacturer has more stability testing results, such as 12 or 18 months, the test manufacturer can contact the FDA to request that the FDA authorize a longer expiration date. When a longer expiration date is authorized, the test manufacturer may send a notice to customers to provide the new authorized expiration date, so the customers know how long they can use the tests they already have.”

Those wondering whether the expiration dates of their at-home tests have been extended can contact the manufacturer or visit its website.

Much has changed since the beginning of the pandemic, including the emergence of more contagious variants, waning immunity from previous infection and initial vaccine doses, and the need for booster shots (or 2nd booster shots).

What hasn’t changed? The need to isolate immediately if you test positive for Covid-19 — regardless of whether you have symptoms, the US Centers for Disease Control and Prevention said.

“Everyone who has presumed or confirmed COVID-19 should stay home and isolate from other people for at least 5 full days (day 0 is the first day of symptoms or the date of the day of the positive viral test for asymptomatic persons). They should wear a mask when around others at home and in public for an additional 5 days,” the CDC’s website says.

Exactly how long you isolate depends on whether you have symptoms and how long they last. According to the CDC:

• You can end isolation after 5 full days if you are fever-free for 24 hours without the use of fever-reducing medication and your other symptoms have improved. (But the loss of taste and smell might last for weeks or months and shouldn’t delay the end of isolation).
• If you still have a fever — or your other symptoms haven’t improved after 5 days of isolation — you should wait until you’re fever-free for 24 hours without the use of fever-reducing medication and your other symptoms have improved. Contact your healthcare provider if you have questions.
• People who are moderately sick from Covid-19 (with symptoms such as shortness of breath or difficulty breathing); very sick from Covid-19 (such as those requiring hospitalization); and those with weakened immune systems should isolate for at least 10 days.
• If you test positive for Covid-19 but never get symptoms even after 5 days, you can leave isolation after 5 full days. But if you develop symptoms during those 5 days, “your 5-day isolation period should start over,” the CDC said.

As for therapies, “it’s important you call your medical provider and ask if you are eligible for therapeutics,” said emergency physician Dr. Leana Wen, professor of health policy and management at the George Washington University Milken Institute School of Public Health.

For those who don’t have a regular medical provider, “the federal government has a therapeutics locator, including a “test-to-treat” option where people can go to get tested, see an urgent care provider, and get the therapies all at the same location,” Wen said. “Your local and state health departments will likely have additional information and resources, too.”

For some people, yes. Paxlovid is a combination of two antiviral medications: nirmatrelvir and ritonavir. It’s now widely available at community pharmacies, the US Food and Drug Administration says.

“There is strong scientific evidence that it reduces the risk of hospitalization and death in patients with mild-to-moderate COVID-19 at high risk for progression to severe disease,” said Dr. John Farley, director of the Office of Infectious Diseases in the FDA’s Center for Drug Evaluation and Research’s Office of New Drugs.

But even doctors are puzzled as to why symptoms can return for some people within two weeks of finishing their Paxlovid. Infectious disease expert Dr. Kent Sepkowitz is one of them. He, too is a “rebounder” whose Covid-19 symptoms improved dramatically after taking Paxlovid, then returned several days later.

Farley said the FDA “is aware of the reports of some patients developing recurrent COVID-19 symptoms after completing a treatment course of Paxlovid. In some of these cases, patients tested negative on a direct SARS-CoV-2 viral test and then tested positive again.”

It’s not clear exactly how often rebound cases happen after taking Paxlovid. As of this spring, a clinical trial of the medication was still ongoing.

In a statement to CNN, Pfizer – the maker of Paxlovid – said that in the clinical trial, a small number of patients in both the group taking placebo pills and the group taking Paxlovid experienced higher viral loads 10 to 14 days after starting treatment compared with their viral loads at day 5.

Because investigators noted this in both groups, Pfizer said it doesn’t believe the phenomenon is tied to the medication. Investigators saw no link between patients’ viral loads and subsequent severe disease.

“We remain confident in its clinical effectiveness at preventing severe outcomes from Covid-19 in high-risk patients,” Pfizer said.

The Novavax vaccine is the 4th and latest Covid-19 vaccine authorized for use in the US. It’s available in a 2-dose series for adults ages 18 and up.

The Novavax vaccine uses totally different technology than the other 3 vaccines available in the US — those from Pfizer/BioNTech, Moderna and Johnson & Johnson.

When the genetic sequence for novel coronavirus was published, Novavax scientists identified the gene for the spike protein and created a modified version of that gene.

Novavax researchers cloned the genes into a baculovirus that infects insects. They then infected moth cells with that virus, prompting them to produce the coronavirus spike protein. These virus-like nanoparticles were harvested to make Novavax’s vaccine.

But the Novavax vaccine is not infectious. “We never touch the coronavirus itself,” said Dr. Gregory Glenn, president of research and development for Novavax.

After the vaccine is given to people, “they make an immune response that’s very much focused just on the spike” protein, Glenn said.

Late-stage trials found that the efficacy of the Novavax vaccine against mild, moderate and severe disease was 90.4%, according to the company. There is not sufficient evidence to determine the impact of the vaccine on transmission of the virus.

In early July, Novavax said its vaccine showed “broad” immune response to currently circulating variants, including Omicron subvariants BA.4 and BA.5.

The Novavax vaccine has some advantages and disadvantages over the others.

“The hallmark of our vaccine is it gives a very strong immune response with very few side effects, and the dose is very small and the vaccine can be stored with normal refrigerated temperatures,” Glenn said. That can make the Novavax vaccine easier to transport and store than the Pfizer and Moderna vaccines, which are more fragile and must be kept frozen.

And people who have been hesitant to get a Covid-19 vaccine might be more comfortable getting Novavax shots because the protein-based approach is a more traditional approach in vaccine development compared to the mRNA vaccines from Pfizer/BioNTech and Moderna.

But the Novavax vaccine is not yet authorized for use as a booster dose, the US Centers for Disease Control and Prevention said.

People who are boosted have more protection against Covid-19 illness and even infection compared to people who are past due for a booster shot — and significantly more protection than those who haven’t been vaccinated at all, studies suggest.

In December 2021, when the Omicron variant became dominant in the US, data from 25 state and local health departments revealed a weekly average of 148.6 Covid-19 cases per 100,000 people who had been fully vaccinated and boosted, according to a study published by the US Centers for Disease Control and Prevention.

Among those who had been fully vaccinated but not yet boosted, the average weekly rate jumped to 254.8 cases per 100,000.

And for those who had not been vaccinated at all, the rate of infection was significantly higher — 725.6 cases per 100,000.

Another study showed booster shots helped prevent people from becoming sick with Omicron.

An analysis of about 13,000 US Omicron cases found that the odds of developing a symptomatic infection were 66% lower for people who had received 3 doses of an mRNA vaccine compared to those who had received only 2 shots, according to a study published in the medical journal JAMA. The gap was even greater between people who had been boosted and those who hadn’t gotten a single dose of vaccine.

A CNN analysis of data from the US Centers for Disease Control and Prevention showed the Johnson & Johnson vaccine had the lowest breakthrough infection rate during a 5-week span starting in late December.

In January, during the Omicron surge, breakthrough infections were highest among those who received the Pfizer/BioNTech vaccine, followed by people who got the Moderna vaccine. Those vaccinated with the Johnson & Johnson shot had the lowest incidence of breakthrough infections.

But any vaccine is better than no vaccine at all. During the Delta and Omicron surges, unvaccinated people were more than twice as likely to get infected compared to those who got Pfizer or Moderna shots. And the odds of getting Covid-19 were more than 3 times higher for unvaccinated people compared to those who got the Johnson & Johnson vaccine.

A study published March 17 in the medical journal JAMA Network Open found the Johnson & Johnson vaccine was 76% effective in preventing Covid-19 infections and 81% effective in preventing Covid-related hospitalizations before and during the Delta surge. The study also showed the J&J vaccine provided lasting immunity at least 6 months after vaccination.

So while studies have shown the Pfizer and Moderna mRNA vaccines prompt a powerful immune response, it can wane over time. Johnson & Johnson’s vaccine might not spark as strong of an immune response shortly after vaccination, but it’s known to have greater durability.

“Over time, the efficacy of the Pfizer and Moderna vaccines goes down, the efficacy of the J&J vaccines remains stable,” said Dr. Dan Barouch, director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center in Boston.

But far more Americans have received the Pfizer or Moderna vaccines than the Johnson & Johnson vaccine.

In December, the CDC recommended the Pfizer and Moderna vaccines over the Johnson & Johnson shot due to data suggesting a rare blood clotting syndrome called TTS is more common among some people who got a J&J vaccine – particularly women ages 30 to 49.

The US Food and Drug Administration has authorized second booster shots of the Pfizer/BioNTech and Moderna vaccines for adults age 50 and older.

Even healthy adults ages 50 and up can get the additional dose as early as 4 months after their 1st booster dose of any Covid-19 vaccine. The US Centers for Disease Control and Prevention has given permissive recommendation for those additional boosters, meaning Americans in that age group can get the extra shot if they want one. But it’s not an official recommendation.

As for the rest of the general public, it’s possible a 4th dose might be recommended for healthy Americans heading into the fall, said Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research. But he said there’s still much uncertainty as to how the pandemic may further evolve.

A fall timeline could be convenient for people who want to get their flu shots at the same time. And respiratory viruses such as coronavirus and influenza tend to peak in the colder months.

Since October, the FDA has allowed Americans ages 12 and up who are severely immune-deficient to get 4 doses of the Pfizer/BioNTech or Moderna vaccines.

According to the CDC, people are considered moderately or severely immunocompromised if they have:

• Been receiving active cancer treatment for tumors or cancers of the blood
• Received an organ transplant and are taking medicine to suppress the immune system
• Received a stem cell transplant within the past 2 years or are taking medicine to suppress the immune system
• Moderate or severe primary immunodeficiency (such as DiGeorge syndrome or Wiskott-Aldrich syndrome)
• Advanced or untreated HIV infection
• Active treatment with high-dose corticosteroids or other drugs that may suppress the immune response

A 2nd booster shot (or the 4th overall dose) of the Moderna or Pfizer/BioNTech mRNA vaccines appeared to be safe and gave a “substantial” boost to immunity when given about 7 months after the 1st booster (or the 3rd overall dose), according to a new study published May 9.

“Fourth-dose Covid-19 mRNA booster vaccines are well tolerated and boost cellular and humoral immunity,” UK scientists wrote in the study published in The Lancet.

“Peak responses after the fourth dose were similar to, and possibly better than, peak responses after the third dose.”

The researchers gave study participants a half dose of the Moderna vaccine or a full dose of the Pfizer vaccine in a random selection in January, about 7 months after they received their first booster. The 2nd booster didn’t seem to have any major side effects. The biggest complaints were arm pain and fatigue.

The additional booster also generated an immune response at day 14 that was higher than that at day 28 after the 3rd dose of the Pfizer or Moderna Covid-19 vaccine.

Moderna’s fourth dose seemed to do slightly better than Pfizer’s, but it’s unclear why. Scientists said 4th doses of either vaccine generated what scientists called a “significant fold change” in protective antibodies and also boosted T-cells.

Antibodies are a first line of immune protection that can stop a virus from infecting cells. T-cells come in later and destroy infected cells. T-cells can’t protect against mild infections, but they can keep infections from progressing to severe disease.

The researchers also found that some people who had higher levels of antibodies before their 4th doses of vaccine had only “limited” boosting. Those with a history of Covid-19 had a similar limited response. The authors say this suggests there may be a ceiling or maximum response that can come with a 4th vaccine dose.

Many Americans were confused when Dr. Anthony Fauci told PBS that the US was “out of the pandemic phase” — but told CNN the next day that the pandemic was not over.

“We don’t have 900,000 new infections a day and tens and tens and tens of thousands of hospitalizations and thousands of deaths,” the director of the National Institute of Allergy and Infectious Diseases told PBS on April 26. “We are at a low level right now. So if you’re saying, ‘Are we out of the pandemic phase in this country?’ We are.”

On April 27, Fauci told CNN the US is still grappling with a pandemic — especially as new Covid-19 cases and hospitalizations have started creeping up again.

“We’re not over the pandemic. Don’t let anybody get the misinterpretation that the pandemic is over,” Fauci told CNN. “But what we are in is a different phase of the pandemic — a phase that’s a transition phase, hopefully headed toward more of a control where you can actually get back to some form of normality without total disruption of society, economically, socially, school-wise, etc.”

Fauci said while coronavirus probably won’t be eradicated, the level of virus in society could be kept very low if people are intermittently vaccinated, possibly every year.

For people who are up to date on their Covid-19 vaccines and boosters, protection against illness from the Omicron variant drops off several months after the last dose – but protection against hospitalization and death remains high, researchers have found.

When it comes to the Omicron variant, an April 20 presentation from the US Centers for Disease Control and Prevention shows that after 2 to 4 months:

• 2 doses of the Johnson & Johnson vaccine are 30% effective against symptomatic infection.
• 1 dose of Johnson & Johnson plus one dose of an mRNA shot from Pfizer/BioNTech or Moderna are 55% effective against symptomatic infection.
• 3 doses of an mRNA vaccine are 63% effective against symptomatic infection.

But people with regular immune functions still had about 86% protection against hospitalization 3 months after a booster shot — though protection among immunocompromised people waned more quickly.

When it comes to protection against hospitalization, “We saw no evidence of waning but in the immunocompromised,” said Sara Tartof, an epidemiologist for Kaiser Permanente in Southern California.

“In the immunocompromised, vaccine effectiveness basically starts low and gets lower.”

Passengers on domestic US flights don’t have to wear masks on planes anymore — though some doctors say it’s a good idea to mask up on public transportation anyway.

On April 13, the Biden administration extended the federal public transportation mask mandate until May 3. An administration official said the reason for the extension was to gather more information and understanding of the BA.2 Omicron subvariant.

But on April 18, a federal judge struck down the mask mandate, saying it exceeded the statutory authority of the US Centers for Disease Control and Prevention and because its implementation violated administrative law.

On April 20, the CDC said “an order requiring masking in the indoor transportation corridor remains necessary for the public health,” and the US Department of Justice appealed the judge’s ruling.

But the appellate filings didn’t immediately include a request to put the court order on hold and reinstate the mask mandate. So for now, Americans on domestic flights, trains and buses are not required to wear masks.

While face masks offer the most protection against the spread of virus-carrying particles in the air when everyone wears them, masks can protect the wearer alone, research suggests, by acting as a barrier between particles and their nose and mouth.

One-way masking — when one person is masked and others are not — depends mainly on two factors: how well your mask fits and how effectively the mask material filters out particles that can carry viruses, said Chris Cappa, a professor of civil and environmental engineering at the University of California, Davis who studies aerosol particles and masks.

Masks like N95s and KN95s will generally be more protective than surgical masks or cloth masks because they can make a tighter seal against your face, he told CNN. So, “a well-fit N95 can reduce the amount of potentially infectious particles that you inhale by more than a factor of 20 times,” Cappa said.

In addition to wearing a high-quality, well-fitting mask, taking steps including getting vaccinated, testing yourself for Covid-19 and making sure spaces you’re in are well-ventilated can make it safe for people — even those at higher risk for more severe illness — to travel, said Dr. Preeti Malani, chief health officer in the Division of Infectious Diseases at the University of Michigan in Ann Arbor.

Lab research suggests BA.2 is resistant to the antibodies of people who were infected with previously dominant variants, such as Alpha and Delta. And BA.2 was almost completely resistant to some monoclonal antibody treatments.

BA.2 also seems to largely escape the immunity created by vaccines. But a booster shot restores protection, making illness after infection about 70% less likely.

A report by the UK’s Health Security Agency showed two doses of vaccine were about 13% effective against getting symptoms from BA.2. But that effectiveness jumped to about 70% two weeks after a booster shot.

The US Centers for Disease Control and Prevention has been collecting wastewater data from about 650 sewersheds — representing about a quarter of the US population — to study how much coronavirus may be in the area.

When it comes to SARS-CoV-2, the virus that causes Covid-19, “wastewater can detect an increase in cases 4 to 6 days before we might see these cases show up through a rise in positive tests,” CDC Director Dr. Rochelle Walensky said.

“People infected with SARS-CoV-2 can shed the virus in their feces, even if they don’t have symptoms,” the CDC’s website says.

“The virus can then be detected in wastewater, enabling wastewater surveillance to capture presence of SARS-CoV-2 shed by people with and without symptoms. This allows wastewater surveillance to serve as an early warning that COVID-19 is spreading in a community,” the CDC says. “Once health departments are aware, communities can act quickly to prevent the spread of COVID-19.”

You can see which surveillance sites have increasing or decreasing amounts of SARS-CoV-2 on this CDC map.

The answers largely depend on where you live and your health status, according to updated guidance from the US Centers for Disease Control and Prevention.

Previously, indoor masking was recommended for those living in areas with “high” or “substantial” transmission of Covid-19. That meant most Americans lived in counties where indoor masking was recommended.

But on February 25, the CDC released a new set of metrics called COVID-19 Community Levels. “CDC recommends using county COVID-19 Community Levels to help determine which COVID-19 prevention measures to use for individuals and communities,” the agency said.

The metrics include:

• The number of new Covid-19 cases per 100,000 people in a community over the past 7 days
• The number of new Covid-19 hospital admissions in a community over the past 7 days
• The percentage of staffed, inpatient hospital beds in a community that are occupied by Covid-19 patients

The CDC uses those metrics to label communities as high, medium or low. You can see what category your county falls under here.

In areas with “high” levels, the CDC advises wearing a mask in public indoor settings – including schools. In areas with “medium” levels, the CDC advises talking with your doctor about wearing a mask if you’re at increased risk for Covid-19. In areas with “low” Covid-19 community levels, there is no recommendation for mask wearing.

But the guidelines are not rules, and there may be places where masks are still required. And there may be times when additional safety measures are needed, the CDC said.

“Recommendations based on COVID-19 Community Levels may not apply to healthcare settings such as hospitals or long-term care facilities,” the CDC said.

“Some community settings such as schools and some high-risk congregate settings such as correctional facilities and homeless shelters might include additional layers of prevention.”

Scientists are trying to develop a universal, “pan-coronavirus” vaccine – one that offers protection against any type of coronavirus, including variants that cause Covid-19.

But such vaccines are “going to take years to develop,” said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.

There are seven known human coronaviruses: four that cause common colds; Middle East Respiratory Syndrome, or MERS; severe acute respiratory syndrome, or SARS; and SARS-CoV-2, the coronavirus that causes Covid-19.

“However, since September of 2020, there have been five SARS-CoV-2 variants of concern: Alpha, Beta, Gamma, Delta and now the current Omicron,” Fauci said January 26.

“I don’t want anyone to think that pan-coronavirus vaccines are literally around the corner in a month or two. It’s going to take years to develop in an incremental fashion. Some of these are already in Phase 1 clinical trials,” Fauci said.

“Don’t forget, however, that our current vaccine regimens do provide strong protection – particularly when used with a booster – against severe coronavirus disease and death,” he said. “So do not wait to receive your primary vaccine regimen and please get your booster if you are eligible.”

The US Food and Drug Administration has limited the use of certain monoclonal antibody treatments for Covid-19 because “data show these treatments are highly unlikely to be active against the omicron variant,” the FDA said.

Those monoclonal antibody treatments include Eli Lilly’s bamlanivimab plus etesevimab and Regeneron’s casirivimab plus imdevimab.

The FDA has decided to limit the use of these treatments for “only when the patient is likely to have been infected with or exposed to a variant that is susceptible to these treatments.”

“Based on Centers for Disease Control and Prevention data, the omicron variant of SARS-CoV-2 is estimated to account for more than 99% of cases in the United States as of Jan. 15. Therefore, it’s highly unlikely that COVID-19 patients seeking care in the U.S. at this time are infected with a variant other than omicron, and these treatments are not authorized to be used at this time,” Dr. Patrizia Cavazzoni, director of the FDA’s Center for Drug Evaluation and Research, said in a January 24 statement.

“This avoids exposing patients to side effects, such as injection site reactions or allergic reactions, which can be potentially serious, from specific treatment agents that are not expected to provide benefit to patients who have been infected with or exposed to the omicron variant.”

Earlier in January, the National Institutes of Health amended its treatment guidelines to no longer recommend those two treatments.

In December, the FDA said sotrovimab was the only monoclonal antibody treatment that remained effective against the new Omicron variant.

However, “there are several other therapies – Paxlovid, sotrovimab, Veklury (remdesivir), and molnupiravir – that are expected to work against the omicron variant, and that are authorized or approved to treat patients with mild-to-moderate COVID-19 who are at high risk for progression to severe disease, including hospitalization or death,” the FDA’s statement said.

“Both COVID-19 and flu can have varying degrees of symptoms, ranging from no symptoms (asymptomatic) to severe symptoms,” the US Centers for Disease Control and Prevention says.

But the outcomes can be different. “In general, COVID-19 seems to spread more easily than flu and causes more serious illnesses in some people,” the CDC says. “Compared with people who have flu infections, people who have COVID-19 can take longer to show symptoms and be contagious for longer.”

Covid-19 and the flu can have similar symptoms, such as:

• Fever or feeling feverish/having chills
• Cough
• Shortness of breath or difficulty breathing
• Fatigue (tiredness)
• Sore throat
• Runny or stuffy nose
• Muscle pain or body aches
• Headache
• Vomiting
• Diarrhea
• Change in or loss of taste or smell, though this is more frequent with Covid-19

But unlike the flu, Covid-19 can lead to long Covid — with symptoms weeks or months after a coronavirus infection.

“Long COVID can happen to anyone who has had COVID-19, even if their illness was mild, or if they had no symptoms,” the CDC says.

If you think you might have Covid-19 symptoms but can’t get tested, doctors say it’s best to assume you have Covid-19 and stay home.

“While the virus that causes COVID-19 and flu viruses are thought to spread in similar ways, the virus that causes COVID-19 is generally more contagious than flu viruses,” the CDC says.

“Also, COVID-19 has been observed to have more superspreading events than flu. This means the virus that causes COVID-19 can quickly and easily spread to a lot of people and result in continual spreading among people as time progresses.”

It’s also possible to have Covid-19 and the flu at the same time. Here’s what that could do to your body.

Some organ transplant centers require patients to be vaccinated against Covid-19 before getting a transplant. But it’s not about punishing the unvaccinated; it’s about trying to maximize the odds of survival.

Organ transplant recipients have an increased risk of severe Covid-19 if they become infected. Patients with organ transplants have their immune systems artificially suppressed during recovery to prevent their bodies from rejecting the new organ. That means adequate vaccination is especially important for organ transplant patients.

“We strongly recommend that all eligible children and adult transplant candidates and recipients be vaccinated with a COVID-19 vaccine that is approved or authorized in their jurisdiction,” said a joint statement from the American Society of Transplant Surgeons, the American Society of Transplantation, and The International Society for Heart & Lung Transplantation.

“We support the development of institutional policies regarding pre-transplant vaccination. We believe that this is in the best interest of the transplant candidate, optimizing their chances of getting through the perioperative and post-transplant periods without severe COVID-19 disease, especially at times of greater infection prevalence.”

The Biden administration is distributing 400 million N95 masks from the Strategic National Stockpile.

Americans can pick up free N95 masks from various pharmacies and community health centers. Each person is limited to 3 free N95 masks.

Well-fitting N95 masks give the best protection against the spread of Covid-19 compared to other masks, such as KN95 masks, disposable surgical masks and cloth masks, the US Centers for Disease Control and Prevention said.

The US Centers for Disease Control and Prevention recently updated its mask guidelines, recommending people “wear the most protective mask you can that fits well and that you will wear consistently.”

“Loosely woven cloth products provide the least protection, layered finely woven products offer more protection, well-fitting disposable surgical masks and KN95s offer even more protection, and well-fitting (National Institute for Occupational Safety and Health)-approved respirators (including N95s) offer the highest level of protection,” the CDC says.

The updated guidance, issued January 14, came after weeks of public debate about whether cloth masks should be ditched in favor of more effective masks due to the highly transmissible Omicron variant.

“Cloth masks are little more than facial decorations. There’s no place for them in light of Omicron,” CNN medical analyst and emergency physician Dr. Leana Wen said in December.

“We need to be wearing at least a 3-ply surgical mask,” she said, such as the ones often sold in drugstores and have an adjustable nose wire. “You can wear a cloth mask on top of that, but do not just wear a cloth mask alone.”

Ideally, in crowded places, “you should be wearing a KN95 or N95 mask,” Wen said. They include materials such as polypropylene fibers that act as both mechanical and electrostatic barriers to help prevent the spread of tiny particles.

When someone is speaking, wearing a face mask can slash the distance that droplets and aerosols travel by half (or more, depending on the type of mask), a recent study published in The Journal of Infectious Diseases suggests.

Without face masks, droplets and aerosols traveled up to about 4 feet when someone was speaking, researchers at the University of Central Florida in Orlando found.

Single-layer cloth masks reduced that maximum distance to about 2 feet. And 3-ply, disposable surgical masks reduced the distance of droplet and aerosol travel all the way down to 0.5 feet, the researchers found. The study did not include KN95 nor N95 masks.

While the CDC acknowledges KN95 and N95 respirators give more protection than surgical masks and cloth masks, it doesn’t say Americans should ditch cloth masks. But cloths masks should have nose wires and multiple layers of fabric that can block light “when held up to bright light source,” the CDC says. They also shouldn’t have exhalation valves, vents or other openings.

“CDC continues to recommend that any mask is better than no mask,” CDC Director Dr. Rochelle Walensky said January 12, “and we do encourage all Americans to wear a well-fitting mask to protect themselves and prevent the spread of Covid-19.”

MIS-C is multisystem inflammatory syndrome in children.

It’s “a rare but serious condition associated with COVID-19 in which different body parts become inflamed, including the heart, lungs, kidneys, brain, skin, eyes, or gastrointestinal organs,” the US Centers for Disease Control and Prevention said.

(A similar syndrome called MIS-A can happen in adults after getting Covid-19.)

With children, MIS-C happens when “the virus induces your body to make an immune response against your own blood vessels” – which can cause inflammation of the vessels, said pediatrician Dr. Paul Offit, director of the Vaccine Education Center at the Children’s Hospital in Philadelphia.

More than 6,400 children have suffered from MIS-C, according to the CDC, and at least 55 have died. The median age of MIS-C patients is 9 years old.

MIS-C “is a rare complication that typically occurs 2 to 4 weeks following SARS-CoV-2 infection,” the American Academy of Pediatrics said. (SARS-CoV-2 is the virus that causes Covid-19.)

And long-term Covid-19 complications can happen even among children who initially had mild or no symptoms, the group said.

“Usually children are picked up incidentally as having (coronavirus). Someone in the family was infected, a friend was infected, so they got a PCR test. And they’re found to be positive. … Then they’re fine,” Offit said.

“Then a month goes by, and they develop a high fever. And evidence of lung, liver, kidney or heart damage. That’s when they come to our hospital.”

The CDC said parents should seek medical care if a child has an ongoing fever plus at least one of the following:

• Stomach pain
• Bloodshot eyes
• Diarrhea
• Dizziness or lightheadedness (signs of low blood pressure)
• Skin rash
• Vomiting

They can — but they work better if you take more than one, Dr. Anthony Fauci said.

Fauci said a single rapid antigen test — like the ones often taken at home, with results in about 15 minutes — are not as sensitive at detecting Omicron as PCR tests, which are processed in a lab.

But “if you do (rapid antigen tests) maybe 2 or 3 times over a few-day period, at the end of the day, they are as good as the PCR,” said Fauci, director of the National Institute of Allergy and Infectious Diseases.

“People should not get the impression that those tests are not valuable. They are very valuable. They are valuable for screening. They’re valuable if you do them more than once in a sequential way to tell you whether you’re infected,” Fauci said.

The US Food and Drug Administration recently said rapid antigen tests may be less likely to detect an Omicron infection — but the tests are still useful.

“Studies are under way to confirm the reason for the apparent decreased sensitivity,” the FDA told CNN in a statement. “Once that is known, adjustments to existing tests can be undertaken by each developer with support from the FDA, if appropriate.”

If you think you have Covid-19 symptoms but can’t get tested, doctors say it’s best to assume you have Covid-19 and stay home.

Even if you don’t have the Omicron variant, the symptoms may be from another contagious virus such as the flu or RSV. So it’s still important to wear a high-quality mask and avoid others whenever possible.

“Given what we currently know about COVID-19 and the Omicron variant, CDC is shortening the recommended time for isolation from 10 days for people with COVID-19 to 5 days, if asymptomatic, followed by 5 days of wearing a mask when around others,” the US Centers for Disease Control and Prevention said.

The decision was motivated by research showing most Covid-19 spread “occurs early in the course of illness, generally in the 1-2 days prior to onset of symptoms and the 2-3 days after,” the CDC said in late December.

“Therefore, people who test positive should isolate for 5 days and, if asymptomatic at that time, they may leave isolation if they can continue to mask for 5 days to minimize the risk of infecting others.”

The CDC said those whose “symptoms are resolving” can also leave isolation after 5 days, as long as they also wear a mask for the next 5 days.

But the CDC was criticized for not mentioning testing for those who want to leave isolation at 5 days.

On January 4, the CDC said those who have access to a rapid antigen test may want to take it toward the end of the 5-day isolation period.

If the test is positive, isolated people are advised to keep isolating until 10 days after their symptoms started. If the test is negative, isolated people can end their isolation — but are advised to wear a mask around other people until day 10.

For those who have a fever or other symptoms that haven’t even improved after 5 days, “you should wait to end your isolation until you are fever-free for 24 hours without the use of fever-reducing medication and your other symptoms have improved,” the CDC said January 4. “Continue to wear a well-fitting mask. Contact your healthcare provider if you have questions.”

It depends on whether you’re fully vaccinated and boosted, the US Centers for Disease Control and Prevention says.

Those who have received a booster shot “do not need to quarantine following an exposure, but should wear a mask for 10 days after the exposure,” the CDC said in a December 27 update.

“For people who are unvaccinated or are more than six months out from their second mRNA dose (or more than 2 months after the J&J vaccine) and not yet boosted, CDC now recommends quarantine for 5 days followed by strict mask use for an additional 5 days,” the CDC said.

“Alternatively, if a 5-day quarantine is not feasible, it is imperative that an exposed person wear a well-fitting mask at all times when around others for 10 days after exposure.”

For anyone who was exposed to someone with Covid-19, it’s a good idea to get tested 5 days after exposure, the CDC said.

“If symptoms occur, individuals should immediately quarantine until a negative test confirms symptoms are not attributable to COVID-19,” the CDC said.

As coronavirus keeps spreading, new mutations and new variants are expected to develop.

But the new Omicron variant has an unusually high number of mutations, including dozens on the spike protein — the structure used by a virus to latch onto and get inside cells under attack.

“It has a lot of mutations — more than 50. That’s a new record,” said Dr. Francis Collins, director of the US National Institutes of Health.

More than 30 of those mutations are in the spike protein — the part of the virus targeted by leading Covid-19 vaccines.

Scientists have been trying to learn how much the Omicron variant might evade the antibodies produced from vaccination or natural infection.

“We worry if the spike protein is of a different shape, maybe the antibodies won’t stick quite as well. That’s the reason for the concern,” Collins said.

“On the other hand, all of the previous variants, which have also had differences in the spike protein, have responded to vaccines — and especially boosters,” he said.

Yes — but early research suggests fully vaccinated people are not likely to get severely sick from the Omicron variant.

In South Africa, where the Omicron variant quickly became dominant, one study suggests two doses of the Pfizer vaccine were 33% protective against infection — but 70% effective in preventing severe illness, including hospitalization.

Health experts say they believe those who are not vaccinated at all remain the most vulnerable.

“This virus will eventually seek out and land on the people who are the most susceptible, and those are the ones that have not been vaccinated, A, and also the ones that have not been boosted,” Los Angeles internal medicine specialist Dr. Jorge Rodriguez said. “It’s not a matter of if. It’s a matter of when.”

Ideally, “everybody should get tested right before that gathering,” CNN medical analyst and emergency physician Dr. Leana Wen said.

If you have very limited tests available, test those who are at the highest risk of recent Covid-19 exposure — not those at the highest risk of illness, Wen said.

In other words, “Don’t test grandma, who’s been hunkering down and being very careful. She’s unlikely to be spreading Covid to everybody else,” Wen said.

“Test the college student who just came home who may have been in bars and restaurants last week. So use those tests in a judicious way and think about the 2-out-of-3 rule: vaccines, masking or testing. You need to have 2 out of 3 things to gather safely.”

“I would say consider the risk level of the people who you’re meeting with,” said Mercedes Carnethon, vice chair of preventive medicine at Northwestern University Feinberg School of Medicine.

She said anyone unable to get tested may want to reconsider meeting with:

• Anyone who is unvaccinated.
• Anyone who is over age 65, regardless of vaccination status. “Vaccinations help. Boosters help. They obviously help to mitigate the severity of the symptoms,” Carnethon said. “But the reality is that the immune response to vaccination and boosting is a little bit lower in older adults whose immune systems aren’t quite as robust and strong.”
• Anyone with underlying conditions such as diabetes, hypertension, obesity, cancer or severe asthma.
• Infants, since it’s unclear how they might fare with Covid-19 — particularly the new Omicron variant.

Families with unvaccinated children who can’t get tested in time should also reconsider meeting with vulnerable relatives, Carnethon said, as those children might be infected but asymptomatic.

But even testing does not guarantee safety, said Dr. Jorge Rodriguez, an Los Angeles internal medicine specialist.

For example, a test taken immediately after a new infection might not detect the virus – “and the test wouldn’t have been positive until tomorrow or the next day,” he said.

“You can certainly get both the flu and Covid-19 at the same time, which could be catastrophic to your immune system,” said Dr. Adrian Burrowes, a family medicine physician in Florida.

In fact, getting infected with one can make you more vulnerable to getting sick with the other, epidemiologist Dr. Seema Yasmin said.

“Once you get infected with the flu and some other respiratory viruses, it weakens your body,” she said. “Your defenses go down, and it makes you vulnerable to getting a second infection on top of that.”

On their own, both Covid-19 and the flu can attack the lungs, potentially causing pneumonia, fluid in the lungs or respiratory failure, the CDC said.

“The two (illnesses) together definitely could be more injurious to the lungs and cause more respiratory failure,” said Dr. Michael Matthay, a professor of medicine at the University of California, San Francisco.

And just like with Covid-19, even young, healthy people can die from the flu.

Doctors say the easiest way to help avoid a flu/Covid-19 double whammy is to get vaccinated against both.

“Yes, you can get a COVID-19 vaccine and a flu vaccine at the same time,” the US Centers for Disease Control and Prevention said.

“If you haven’t gotten your currently recommended doses of COVID-19 vaccine, get a COVID-19 vaccine as soon as you can,” the CDC said.

The ability to get both vaccines at the same time can make it more convenient for Americans to try to stay healthy, said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.

“If that means going in and getting the flu shot in one arm (and) the Covid shot in the other, that’s perfectly fine,” Fauci said.

But don’t assume you’re protected right afterward. “Remember, after you are vaccinated, your body takes about two weeks to develop antibodies that protect against flu,” the CDC said.

Similarly, you’re not fully vaccinated against Covid-19 until two weeks after the final dose.

Yes. In fact, the first confirmed Omicron-related death in the US was a man who previously had Covid-19.

The Texas man, in his 50s, had not been vaccinated, Harris County health officials said.

For months, the US Centers for Disease Control and Prevention has said vaccines give stronger protection against Covid-19 than previous infection alone.

“If you have had Covid-19 before, please still get vaccinated,” CDC Director Dr. Rochelle Walensky said in August, citing research published during a Delta variant surge. “This study shows you are twice as likely to get infected again if you are unvaccinated.”

With the new Omicron variant, the risk of getting reinfected is 5.4 times higher with Omicron than it was with Delta, according to a team of disease modelers at Imperial College London.

“This suggests relatively low remaining levels of immunity from prior infection,” the team wrote in a December report.

Health experts say the best way to help protect against the Omicron variant is to get vaccinated and boosted.

“I think that depends on people’s individual risk tolerance,” CNN medical analyst and emergency physician Dr. Leana Wen said.

Some, like Dr. Peter Hotez, decided to cancel a planned visit from in-laws this holiday season.

“Unfortunately, I had to ask them not to come because I thought that it was a little too risky for them in terms of travel with all the Omicron circulating,” said Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine.

For families who still want to get together with extended relatives, Wen suggests following the “2-out-of-every-3 rule.”

“We have 3 major tools at our disposal: vaccination, testing and masking,” she said.

“We should have 2 out of every 3 things. And so if you’re not vaccinated, you should be masking, and if you’re gathering with people, testing,” Wen said.

“If you are vaccinated, also get that booster, too. But if you want to get together with people indoors without masks, then make sure that people are tested that same day. If you’re unable to get that test, people should still be wearing masks indoors.”

For children too young to get vaccinated — and who obviously can’t wear a mask while eating — “the key in that case is to surround the unvaccinated kids with others who are vaccinated,” Wen said.

“This is classic herd immunity — others protect the young kids who can’t mask. And if everyone tests, that’s the second layer of protection.”

The US Centers for Disease Control and Prevention still says people are fully vaccinated:

• 2 weeks after their second dose in a 2-dose series, such as the Pfizer or Moderna vaccines, or
• 2 weeks after a single-dose vaccine, such as Johnson & Johnson’s Janssen vaccine

But the CDC has recommended additional booster shots for all adults who are 2 months past their Johnson & Johnson vaccination or 6 months past their Moderna vaccination.

The CDC has also recommended a booster shot of the Pfizer vaccine for everyone ages 16 and up who are 6 months past their second dose.

Some doctors say the definition of “fully vaccinated” needs to change to include booster doses.

“I’ve always said this is a three-dose vaccine,” said vaccinologist Dr. Peter Hotez, a professor and dean of the National School of Tropical Medicine at Baylor College of Medicine.

“The reason is when you get that third dose, you get a 30- to 40-fold rise in virus-neutralizing antibodies, and therefore there’s more spillover protection against new variants – including Omicron,” Hotez said December 15.

“The third dose gives you 70% to 75% protection against symptomatic illness.”

Dr. Anthony Fauci said it’s inevitable that the definition of “fully vaccinated” will change.

“It’s going to be a matter of when, not if,” said the director of the National Institute of Allergy and Infectious Diseases.

“For me, as a public health person, I just say get your third shot,” Fauci said, referring to eligible Pfizer and Moderna vaccine recipients.

“Forget about what the definition is. I just want to see people be optimally protected. And for me, that’s unequivocally and unquestionably getting a third shot boost.”

“If you have difficulty reaching a vaccination site, you may be able to get an in-home vaccination,” the CDC says.

The CDC suggests contacting the following to see if they provide at-home vaccination in your area:

• Your doctor or health care provider
• The hotline for Medicare recipients at 1-800-633-4227 (TTY 1-877-486-2048)
• Your state health department or 211
• The Disability Information and Access Line (DIAL) 1-888-677-1199
• Services for older adults and their families at the Eldercare Locator or 1-800-677-1116

The CDC lists active and inactive ingredients for each of the three coronavirus vaccines used in the US.

“None of the vaccines contain eggs, gelatin, latex, or preservatives,” the CDC said.

And contrary to popular myths, the vaccines don’t have microchips and can’t make you magnetic.

“All COVID-19 vaccines are free from metals such as iron, nickel, cobalt, lithium, rare earth alloys or any manufactured products such as microelectronics, electrodes, carbon nanotubes, or nanowire semiconductors.”

No.

Diagnostic tests like PCR tests and rapid antigen tests can help detect whether you’ve been infected with coronavirus. But they can’t tell you exactly which strain you have.

It takes another layer of testing, involving genetic sequencing, to determine what strain or variant caused the infection.

“The answer is no,” said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.

“If you are eligible … don’t wait,” Fauci said.

“Get that extra boost now because we know when you do that, the level of antibodies that rise and go up following a boost is much, much higher than the peak level that you get after your second dose of a two-dose vaccine,” he said.

“Our experience with variants such as the Delta variant is that even though the vaccine isn’t specifically targeted to the Delta variant, when you get a high enough level of an immune response, you get spillover protection even against a variant that the vaccine wasn’t specifically directed at.”

Pfizer and Moderna have been working on Omicron-specific booster shots — just in case they might be needed.

But even if Omicron-specific shots are needed, it would take a while to get them rolled out to the public.

Since May, the World Health Organization has been assigning Greek letters to notable new coronavirus variants.

Before Omicron, the last two variants of interest or concern were called Lambda and Mu. The next letter in the Greek alphabet is Nu, followed by Xi.

But WHO skipped over Nu and Xi and went straight to Omicron for the latest variant of concern, which has the scientific name B.1.1.529.

The reason? “Nu is too easily confounded with ‘new’ and Xi was not used because it is a common surname,” WHO said in an email to CNN.

“And WHO best practices for naming new diseases suggest ‘avoiding causing offense to any cultural, social, national, regional, professional or ethnic groups.’”

Pfizer said its vaccine is safe and 90.7% effective against symptomatic Covid-19 in children ages 5 to 11, based on clinical trial data. Trial participants who got the vaccine received two doses, spaced three weeks apart.

After monitoring trial participants for three months after the shots, there were no serious side effects such as myocarditis or pericarditis, Pfizer said.

“The side effects we’re seeing in the kids are really identical to what we’re seeing in adults,” said Dr. Bob Frenck, director of the Vaccine Research Center at Cincinnati Children’s Hospital, one of the Pfizer pediatric trial sites. Such side effects include a sore arm, fatigue, headache and fever in about 10% of children. Those side effects don’t last more than a day or two.

Separately, Moderna has been testing various doses of its Covid-19 vaccine in children. On October 25, Moderna said interim trial results showed its vaccine was well tolerated and generated a robust immune response in children ages 6 to 11.

Some participants had side effects such as fatigue, headache, fever and pain at the injection site. Moderna said planned to submit its data to the FDA.

“I wouldn’t wait,” said Dr. Paul Spearman, a member of the US Food and Drug Administration’s Vaccines and Related Biological Products Advisory Committee.

He said data presented to the committee by Pfizer “showed that a 10-microgram dose — so a third of the dose that is licensed for adults — was equally effective in terms of generating neutralizing antibodies, one of the most important means of protecting people from Covid-19.”

One advantage of the smaller (but equally effective) doses for children was reduced side effects, said Dr. Bob Frenck, director of the Vaccine Research Center at Cincinnati Children’s Hospital — one of the Pfizer pediatric trial sites.

“So, one-third of the dose that we’re giving adults, or even one-third of the dose that was used in 12-year-olds and above, was just as immunogenic. We got just as good an immune response as the 30-microgram dose, and there were less side effects,” Frenck said.

“A lot of people are asking us: ‘Does this mean you’re giving us less of a vaccine?’ I said, well, we’re giving you less antigen, but their immune response is so good that they’re making the same immune response – so there’s no need to give more vaccine,” he said.

For parents of larger 10- or 11-year-olds who are worried a pediatric dose might not be enough, weight is not important when it comes to vaccines, said Dr. Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia.

Pfizer said data from its vaccine trial that included 2,268 children ages 5 to 11 showed the vaccine is safe and generates “robust” antibody response.

It said the “preferred dose for safety, tolerability and immunogenicity” among that age group was 10 micrograms per dose – one-third the dosage for those ages 12 and older.

But just like with teens and adults, children ages 5 to 11 need to get two doses spaced three weeks apart.

In this case, weight isn’t important, said Dr. Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia.

“I think people have a misconception about the way vaccines work. They think of them in the same way as drugs. If you give, for example, an antibiotic like amoxicillin, your weight matters because the antibiotic is distributed throughout your bloodstream,” Offit said.

“That’s not true with vaccines. With vaccines, you get those as a shot in the arm, and that’s taken up by the local draining lymph nodes. So really weight doesn’t matter.”

Adolescents ages 12 and up who get the Pfizer/BioNTech vaccine get the same dosage that adults get – 30 micrograms per dose.

Researchers have been trying to see which doses give the best combination of high efficacy and minimal side effects among younger children.

In September, Pfizer announced its Covid-19 vaccine was safe and generated a “robust” antibody response in children ages 5 to 11. It said the “preferred dose for safety, tolerability and immunogenicity” among that age group was 10 micrograms per dose – one-third the dosage for teens and adults.

No vaccine is 100% effective, but the Covid-19 vaccines significantly reduce the chances of severe illness and death — across multiple age groups.

For adults under age 50, the rate of Covid-19 hospitalizations among those unvaccinated was 15 times higher than for those fully vaccinated, according to August data from the US Centers for Disease Control and Prevention. Among those ages 50 to 64, the hospitalization rate is 31 times higher for unvaccinated people.

And the risk of dying from Covid-19 is more than 11 times higher for unvaccinated adults than it is for vaccinated adults, according to the CDC data.

For seniors, who are more susceptible to severe Covid-19, that gap is smaller. Among those 80 and older, the risk of dying from Covid-19 in August was about five times higher among those unvaccinated compared to those fully vaccinated.

Of the breakthrough cases resulting in death, 85% were among people age 65 and older, according to the CDC.

But those cases are extremely rare. As of October 12, about 7,178 breakthrough Covid-19 infections resulting in death had been reported, and 187 million people had been fully vaccinated, according to the CDC. In other words, about 0.004% of fully vaccinated people died of Covid-19.

More than 72,000 children have been hospitalized with Covid-19 since August 2020, according to the CDC.

And it’s not just children with preexisting conditions getting hospitalized.

Almost half – 45.7% – of children hospitalized with Covid-19 between March 2020 and October 2021 had no known underlying condition, according to CDC data from almost 100 US counties.

And while pediatric Covid-19 deaths are rare, at least 1,015 children in the US have died from Covid-19, according to CDC data.

During the Delta variant surge, some hospitals saw an increase in pediatric Covid-19 patients.

At the University of Mississippi Medical Center, “we’ve had infants as small as 6 to 8 months old up to the teenage years,” Associate Vice Chancellor for Clinical Affairs Dr. Alan Jones said in July.

“It appears as though this particular variant, the Delta variant, while being more infectious is also causing more children to be symptomatic,” he said.

“Whether that just is that it causes a little more severe illness than other variants or that it is just more prevalent — and so we’re seeing more symptomatic cases — we’re not sure … but it’s probably multifactorial.”

Some youngsters have suffered long-term effects from Covid-19 or multisystem inflammatory syndrome in children (MIS-C) – a rare but potentially serious condition that can happen in children weeks after a coronavirus infection.

More than 6,400 children have suffered from MIS-C, according to the CDC.

If possible, buy a few different brands of masks and see which one is most comfortable for your child, emergency physician and CNN Medical Analyst Dr. Leana Wen said.

“Different people have different comfort levels,” she said. For example, some children might like one brand of kid-sized surgical masks over another.

Other children might feel more comfortable wearing kid-sized KN95 masks, which allow more room for the nose and mouth.

“The most important thing is to find the best that you can consistently wear throughout the day,” Wen said. “You don’t want to find a mask that you’re trying to pull off your face every 20 minutes.”

Buying masks with fun designs or with your child’s favorite characters on them can also help, psychologist Christopher Willard said. Children can also customize their masks by drawing on them with markers.

And, of course, parents can set a good example by also wearing a mask.

Data suggests side effects from a booster dose of a mRNA Covid-19 vaccine have been similar in frequency and type to those seen after second doses — and were “mostly mild or moderate and short-lived,” CDC Director Dr. Rochelle Walensky said September 28.

The two-shot vaccines from Moderna and Pfizer both use genetic material called messenger RNA, or mRNA, to deliver immunity.

Walensky cited a study published that day by the CDC. It covers 22,191 people who received a third dose of an mRNA vaccine and made reports to CDC’s v-safe system, a voluntary, smartphone-based app that lets people report how they feel after they’ve been vaccinated. The reports were made from August 12 (when the US Food and Drug Administration OK’d additional doses for certain immunocompromised people) through September 19.

Among those 22,191 who made reports, about 7,000 – nearly 32% – reported any health impacts. More than 6,200 – about 28% – reported they were unable to perform normal daily activities, mostly commonly on the day after vaccination.

The most common complaints were injection site pain (71%), fatigue (56%) and a headache (43.4%). Of those who reported general pain, only about 7% described it as “severe.” Severe was defined as pain that makes “daily activities difficult or impossible.”

Nearly 2% said they sought medical care and 13 people were hospitalized, but it was not clear from the v-safe reports why these people sought medical care or were hospitalized. Those who sought medical attention are contacted by staff members from the Vaccine Adverse Event Reporting System and encouraged to make a report, it said.

Of the 22,191 people, 12,591 happened to have tracked how they felt after all three doses. Out of that smaller group, 79.4% reported a local reaction to the third shot and 74.1% reported a systemic reaction. That’s similar to what they reported after a second dose, when 77.6% reported local reactions and 76.5% reported systemic reactions.

No unexpected patterns of adverse reactions were identified, the report said.

Some people reported getting a booster from different company than their original vaccine or getting a second dose of the single-dose Johnson & Johnson vaccine, but the report’s authors said the numbers in both cases were too small to draw any conclusions.

Contact the vaccination provider site where you received your vaccine. “Your provider should give you a new card with up-to-date information about the vaccinations you have received,” the CDC said.

“If the location where you received your COVID-19 vaccine is no longer operating, contact your state or local health department’s immunization information system (IIS) for assistance,” the CDC said.

“Please contact your state or local health department if you have additional questions about vaccination cards or vaccination records.”

To be clear: “CDC does not maintain vaccination records or determine how vaccination records are used, and CDC does not provide the CDC-labeled, white COVID-19 vaccination record card to people. These cards are distributed to vaccination providers by state and local health departments,” the agency said.

And don’t try to use a forged or fraudulent vaccination card — that could land you in prison.

“COVID-19 vaccination is recommended for all people 12 years and older, including people who are pregnant, breastfeeding, trying to get pregnant now, or might become pregnant in the future,” the CDC said.

“Evidence about the safety and effectiveness of COVID-19 vaccination during pregnancy has been growing,” the CDC said in an August 11 update.

Scientists say Covid-19 — not the Covid-19 vaccine — can put a woman at higher risk of severe illness during pregnancy.

Covid-19 can lead to “adverse pregnancy outcomes, such as preterm birth,” said Sascha Ellington, team lead for emergency preparedness and response in the CDC’s Division of Reproductive Health.

“This vaccine can prevent Covid-19, and so that’s the primary benefit.”

“Infections in fully vaccinated people (breakthrough infections) happen in only a small proportion of people who are fully vaccinated, even with the Delta variant,” the CDC said.

“Moreover, when these infections occur among vaccinated people, they tend to be mild.”

Even for those who get breakthrough infections, a study published in September found vaccines can reduce the chances of having long-term Covid-19 symptoms.

“We found that the odds of having symptoms for 28 days or more after post-vaccination infection were approximately halved by having two vaccine doses,” researchers wrote in the study published in the journal The Lancet Infectious Diseases.

“This result suggests that the risk of long COVID is reduced in individuals who have received double vaccination, when additionally considering the already documented reduced risk of infection overall.”

“Yes, you should be vaccinated regardless of whether you already had COVID-19,” the CDC says.

“Evidence is emerging that people get better protection by being fully vaccinated compared with having had COVID-19. One study showed that unvaccinated people who already had COVID-19 are more than 2 times as likely than fully vaccinated people to get COVID-19 again,” the CDC’s website says.

“If you were treated for COVID-19 with monoclonal antibodies or convalescent plasma, you should wait 90 days before getting a COVID-19 vaccine. Talk to your doctor if you are unsure what treatments you received or if you have more questions about getting a COVID-19 vaccine.”

The concept that immunity gained through vaccination may be stronger or lasts longer than the immunity achieved from previous infection isn’t new.

“Many of the vaccines that we’ve made in history are actually stronger than the virus is itself at creating immunity,” epidemiologist Dr. Larry Brilliant said.

No. “The greatest risk of transmission is among unvaccinated people who are much more likely to get infected, and therefore transmit the virus,” the CDC said about the Delta variant on August 26.

A study published by the CDC in late August showed vaccinated people were 5 times less likely to get infected than unvaccinated people.

When a fully vaccinated person does get a breakthrough infection, “your chances of having symptoms go down by 8-fold” compared to an unvaccinated person, National Institutes of Health Director Dr. Francis Collins said August 1.

“People infected with the Delta variant, including fully vaccinated people with symptomatic breakthrough infections, can transmit the virus to others,” the CDC said. “CDC is continuing to assess data on whether fully vaccinated people with asymptomatic breakthrough infections can transmit the virus.”

Even if a vaccinated person gets a breakthrough infection and is contagious, “vaccinated people appear to spread the virus for a shorter time,” the CDC said.

“For people infected with the Delta variant, similar amounts of viral genetic material have been found among both unvaccinated and fully vaccinated people. However, like prior variants, the amount of viral genetic material may go down faster in fully vaccinated people when compared to unvaccinated people,” the CDC said. “This means fully vaccinated people will likely spread the virus for less time than unvaccinated people.”

Avoiding vaccination can harm your loved ones and help create even more contagious or more dangerous variants for everyone, doctors say.

Full vaccination reduces the chances of getting and spreading coronavirus.

Children too young to be vaccinated and people who are immunocompromised also rely on the vaccination of others to help protect them, said Dr. William Schaffner, a professor in the Division of Infectious Diseases at Vanderbilt University Medical Center.

But vaccination is also important to help prevent more contagious or more dangerous variants from forming — such as one that might evade vaccines and harm those who are fully vaccinated.

“If we are going to continue to allow this virus to spread, we’re going to continue to allow … variants to be created,” said Dr. Paul Offit, director of the Vaccine Education Center at the Children’s Hospital in Philadelphia.

Viruses frequently mutate as they replicate among infected people. If the mutations are significant, they can lead to a more contagious variant.

“Think of a virus as a necklace full of different-colored beads,” board-certified internist Dr. Jorge Rodriguez said.

“In position No. 1, you need a red bead. Position No. 2 is a green bead. That’s the genetic code – that sequence of bead colors,” he said.

“When a virus replicates, it is supposed to make an exact replica of those bead colors. But every once in a while, maybe a green bead gets into where a red bead is supposed to be.”

When mutations give the virus an advantage — such as the ability to replicate faster or to hide from the immune system – that version will outcompete others.

The only way to get rid of variants is to lower the number of infections, said Penny Moore, an expert in viruses at South Africa’s National Institute for Communicable Diseases.

That’s a big reason why doctors say people should get vaccinated as soon as they can. Those who don’t get vaccinated aren’t just risking their own health — they’re also jeopardizing the health of others.

“Unvaccinated people are potential variant factories,” Schaffner said. “The more unvaccinated people there are, the more opportunities for the virus to multiply.”

No. Businesses have been able to issue Covid-19 vaccine mandates for months, back when all three vaccines used in the US had emergency use authorization from the US Food and Drug Administration, according to the US Equal Employment Opportunity Commission.

But full FDA approval could make legal challenges against vaccine mandates more difficult.

The Pfizer/BioNTech vaccine is the only one that has been granted full FDA approval — specifically, for people ages 16 and up. The Moderna and Johnson & Johnson vaccines both have emergency use authorization (EUA) for use in adults ages 18 and up.

Pfizer/BioNTech started applying for full approval in May. In June, Moderna announced it started applying for full approval of its coronavirus vaccine. As of August 23, Johnson & Johnson had not yet filed for full FDA approval of its vaccine.

On August 25, Moderna announced it had finished its submission for full FDA approval. The FDA has been assessing Moderna’s application, US Surgeon General Dr. Vivek Murthy said.

Murthy said he said he anticipates Johnson & Johnson will submit its application in the near future.

But regardless of which vaccine people receive, “getting vaccinated now with any of the three vaccines is still your fastest path to protection … particularly against hospitalization and death from the virus,” the surgeon general said.

If there are tissues nearby, you can take your mask off and sneeze into the tissue before putting your mask back on, CNN Chief Medical Correspondent Dr. Sanjay Gupta said.

For kids in school — or anyone else who might have to wear a mask all day — keep a backup mask in a baggie in case the first mask gets dirty. You can put the dirty mask in the baggie.

It’s also a good idea to keep backup masks in your car in case of any mask accidents.

If you think you might have Covid-19 symptoms, “please get tested regardless of your vaccination status,” US Surgeon General Dr. Vivek Murthy said.

“We know the symptoms of Covid-19 mimic the symptoms of the flu or cold initially. It can be a runny nose or fatigue or other such symptoms. In those cases, it is important for people to get tested.”

It’s impossible to get Covid-19 from a vaccine because there is no coronavirus in any of the vaccines used in the US.

But Covid-19 vaccines don’t take full effect until 2 weeks after your final dose — “so a person could get sick if the vaccine has not had enough time to provide protection,” the CDC said.

Those who are fully vaccinated are much less likely to get infected than unvaccinated people, the CDC said. In addition, “COVID-19 vaccines reduce the risk of people spreading COVID-19.”

But while Covid-19 vaccines are highly effective, they’re not perfect. The vaccines require an immune system response to work, so millions of Americans who are immunocompromised or take drugs that suppress the immune system might not get as much protection from a vaccine as others do.

The good news: When rare breakthrough infections do happen in vaccinated people, they’re usually less severe, CDC research shows.

But it’s especially important for unvaccinated people who have Covid-19 symptoms to get tested. Unvaccinated people can spread coronavirus more easily than vaccinated people, the CDC said.

“Delay travel until you are fully vaccinated,” the CDC says.

For those traveling within the US, you “do NOT need to get tested or self-quarantine if you are fully vaccinated or have recovered from COVID-19 in the past 3 months. You should still follow all other travel recommendations,” the CDC says.

Americans traveling internationally should learn about the Covid-19 restrictions in place at their destination. Those flying back home to the US must provide proof that they have recently tested negative for coronavirus or recently recovered from Covid-19. They should also get a viral test 3 to 5 days after coming home, the CDC says.

For those who aren’t fully vaccinated but must travel, the guidelines are much tougher. The CDC says it’s important to wear a mask; get tested within three days before traveling; maintain physical distance from anyone not traveling with you; and quarantine for 10 days after you return home. (That quarantine period can be reduced to 7 days if you get tested 3 to 5 days after coming home.)

The Delta Plus variant (B.1.617.2.1) is a newer and slightly changed offshoot of the highly contagious Delta variant (B.1.617.2).

All variants carry clusters of mutations. Delta Plus is different from Delta because it has an extra mutation called K417N. That mutation affects the spike protein – the part of the virus that attaches to human cells it infects.

The Indian government’s Covid-19 genome sequencing body said the Delta Plus variant exhibits several worrying traits such as increased transmissibility, stronger binding to receptors of lung cells, and a potential reduction in antibody response.

It’s not yet clear what effect the mutation may have on vaccine efficacy. But it could give the variant “significant vaccine escape properties,” warned Julian Tang, professor of respiratory sciences at the University of Leicester.

Most of the coronavirus vaccines are designed to train the body to recognize the spike protein, or parts of it – which is where Delta Plus’ extra mutation is.

But there isn’t enough evidence to determine anything conclusively yet. The World Health Organization is tracking Delta Plus to determine its transmissibility and severity, said Maria Van Kerkhove, WHO’s technical lead on Covid-19.

The US is among at least 11 countries that have reported cases of the emerging Delta Plus variant. But Delta Plus has not made up a significant share of sequenced Covid-19 cases in the US, according to data from the CDC.

“It is a normal human reaction to be afraid,” pediatrician Dr. Edith Bracho-Sanchez said. “They’re having a normal reaction, and perhaps they haven’t been able to sit down with their physician.”

She suggests finding a time to have a calm, rational conversation — when neither person is angry or likely to start a fight.

“The first thing I would say is ‘I get it. I totally get where you’re coming from and I understand that you’re concerned about this,’” Bracho-Sanchez said.

It’s also important to cite scientific data — like the truth about side effects, the safety of Covid-19 vaccines and why it’s important for young, healthy people to get vaccinated.

No.

It’s literally impossible to get Covid-19 from any of the vaccines used in the US because none of them contains even a piece of actual coronavirus.

This article explains how each vaccine was made.

“It’s all free. The government is paying for this,” said Dr. Paul Offit, director of the Vaccine Education Center at the Children’s Hospital in Philadelphia.

Some people have reported feeling temporary, flu-like symptoms. Don’t freak out if this happens to you, health experts say.

“These are immune responses, so if you feel something after vaccination, you should expect to feel that,” said Patricia Stinchfield of Children’s Hospitals and Clinics of Minnesota.

“And when you do, it’s normal that you have some arm soreness or some fatigue or some body aches or even some fever,” Stinchfield said.

Read more about what to do if you do get side effects and why side effects are often a good sign.

The Pfizer/BioNTech vaccine has shown no serious safety concerns, Pfizer said. Pfizer has said side effects “such as fever, fatigue and chills” have been “generally mild to moderate” and lasted one to two days.

Moderna said its vaccine did not have any serious side effects. It said a small percentage of trial participants had symptoms such as body aches and headaches.

With the Johnson & Johnson vaccine, the most common side effects were pain at the injection site, headache, fatigue and muscle pain. While the CDC recommends the Johnson & Johnson vaccine, “women younger than 50 years old especially should be aware of the rare but increased risk of thrombosis with thrombocytopenia syndrome (TTS),” the agency says. “TTS is a serious condition that involves blood clots with low platelets. There are other COVID-19 vaccine options available for which this risk has not been seen.”

Some Covid-19 survivors have reported problems weeks or months after testing positive.

Even young adults have suffered long-lasting symptoms such as shortness of breath, chronic fatigue, brain fog, long-term fever, coughing, memory loss, and the inability to taste or smell.

One CDC study found 35% of survivors surveyed still had symptoms two to three weeks after their coronavirus tests:

• In the 18-to-34 age group, 26% said they still had symptoms weeks later.
• In the 35-to-49 age range, 32% were still grappling with the effects weeks later.
• For those 50 and older, 47% said they still had symptoms weeks later.

And the risk of death from coronavirus-related heart damage seems to be far greater than previously thought, the American Heart Association said.

Inflammation of the vascular system and injury to the heart occur in 20% to 30% of hospitalized Covid-19 patients and contribute to 40% of deaths, the AHA said. AHA President Dr. Mitchell Elkind said cardiac complications of Covid-19 could linger after recovering from coronavirus.

Aerosolized spread is the potential for coronavirus to spread not just by respiratory droplets, but by even smaller particles called aerosols that can float in the air longer than droplets and can spread farther than 6 feet.

Respiratory aerosols and droplets are released when someone talks, breaths, sings, sneezes or coughs. But the main difference is size.

Respiratory droplets are bigger – between 5 and 10 microns in diameter. (For perspective, a human hair is typically 60 to 120 microns wide.)

“If you have droplets that come out of a person, they generally go down within 6 feet,” said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.

But aerosols (aka droplet nuclei) are smaller – less than 5 microns in diameter, according to the World Health Organization.

“Aerosol means the droplets don’t drop immediately,” Fauci said. “They hang around for a period of time.”

This becomes “very relevant” when you are indoors and there is poor ventilation, he said.

Multiple case studies suggest coronavirus can spread well beyond 6 feet through airborne transmission, such as during choir practices, said Dr. Amy Compton-Phillips, chief clinical officer of Providence Health System.

In Washington state, for example, 53 members of a choir fell sick and two people died after one member attended rehearsals and later tested positive for Covid-19.

Last July, 239 scientists backed a letter urging public health agencies to recognize the potential for aerosolized spread.

“There is significant potential for inhalation exposure to viruses in microscopic respiratory droplets (microdroplets) at short to medium distances (up to several meters, or room scale), and we are advocating for the use of preventive measures to mitigate this route of airborne transmission,” the letter said.

The Crisis Text Line is available texting to 741741. Trained volunteers and crisis counselors are staffed 24/7, and the service is free.

The Substance Abuse and Mental Health Services Administration Disaster Distress Helpline provides 24/7, 365-day-a-year crisis counseling and support to people experiencing emotional distress related to disasters. Call 1-800-985-5990 or text TalkWithUs to 66746 to connect with a trained crisis counselor.

For health care professionals and essential workers, For the Frontlines offers free 24/7 crisis counseling and support for workers dealing with stress, anxiety, fear or isolation related to coronavirus.

For more resources, check out CNN’s guide to giving and getting help during the pandemic.

More than 40% of US adults have at least one underlying condition that can put them at higher risk of severe complications, according to the CDC.

Those conditions include obesity, chronic obstructive pulmonary disease, heart disease, diabetes, and chronic kidney disease, according to the CDC.

People who have cancer, an organ transplant, sickle cell anemia, poorly controlled HIV or any autoimmune disorder are also at higher risk.

Covid-19 patients with pre-existing conditions — regardless of their age — are 6 times more likely to hospitalized and 12 times more likely to die from the disease than those who had no pre-existing conditions, CNN Chief Medical Correspondent Dr. Sanjay Gupta said.

While young, healthy people are less likely to die from Covid-19, many are suffering long-term effects from the disease.

Unvaccinated people from different households in a car should wear face masks, said Dr. Aaron Hamilton of the Cleveland Clinic.

“You should also wear one if you’re rolling down your window to interact with someone at a drive-thru or curbside pickup location,” Hamilton said.

It’s also smart to keep the windows open to help ventilate the car and add another layer of safety, said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.

Coronavirus and Covid-19 are not the same thing, but sometimes the terms can be used interchangeably.

This “novel coronavirus” is novel because it just emerged in humans in late 2019. There have been six other coronaviruses known to infect humans, such as SARS (circa 2003) and MERS (circa 2012).

“Coronaviruses are named for the crown-like spikes on their surface,” or coronas, the CDC says. The scientific name for this novel coronavirus is SARS-CoV-2, which stands for “severe acute respiratory syndrome coronavirus 2.”

Covid-19, however, is the disease caused by the novel coronavirus. The letters and numbers in “Covid-19” come from “Coronavirus disease 2019.”

About 2% to 5% of babies born to mothers with Covid-19 tested positive for coronavirus within the first four days of life, according to the American Academy of Pediatrics.

But infected mothers are unlikely to pass coronavirus to their newborns when appropriate precautions are taken, according to a study published in The Lancet Child & Adolescent Health.

In that study, researchers found no cases of viral transmission among 120 babies born to 116 mothers with coronavirus — even when both shared a room and the mothers breastfed.

But the babies remained 6 feet apart from their mothers, except while breastfeeding. The moms also wore surgical masks when handling their newborns and followed proper hand and breast washing procedures.

That’s not recommended right now, according to the US Organ Procurement and Transplantation Network.

“This guidance may change as more becomes known about the course and treatment of COVID-19,” the network said.

“Donation and transplant clinicians should apply their medical judgment in instances where test results are pending at the time of organ offers.”

Yes, that’s a good idea because cell phones are basically “petri dishes in our pockets” when you think about how many surfaces you touch before touching your phone.

You should regularly disinfect your mobile phone anyway, with or without a coronavirus pandemic.

“There’s probably quite a lot of microorganisms on there, because you’re holding them against your skin, you are handling them all the time, and also you’re speaking into them,” said Mark Fielder, a professor of medical microbiology at Kingston University.

“And speaking does release droplets of water just in normal speech. So it’s likely that a range of microbes – including Covid-19, should you happen to be infected with that virus – might end up on your phone.”

Watch the best ways to disinfect your cell phone here.

There are certainly more risks if you’re not fully vaccinated.

Coronavirus often spreads more easily indoors rather than outdoors — especially if you’re indoors for an extended period of time.

Researchers have also found that heavy breathing and singing can propel aerosolized viral particles farther and increase the risk of transmission.

During one fitness instructor workshop, about 30 participants with no symptoms trained intensely for four hours, according to research published by the CDC. Eight participants later tested positive, and more than 100 new cases of coronavirus were traced back to that fitness workshop.

To help mitigate the risk, many gyms are limiting capacity or requiring masks.

And while health experts have recommended staying 6 feet away from others, it’s smart to keep even more distance than that at the gym.

“With all the heavy breathing, you may even want to double the usual 6 feet to 12 feet, just to be safe,” CNN Chief Medical Correspondent Dr. Sanjay Gupta said.

Doctors say wearing eye protection (in addition to face masks) could help some people, but it’s not necessary for everyone.

Teachers who have younger students in the classroom are “likely to be in environments where children might pull down their masks, or not be very compliant with them,” epidemiologist Saskia Popescu said. “There is concern that you could get respiratory droplets in the eyes.”

If you’re a health care worker or taking care of someone at home who has coronavirus, it’s smart to wear eye protection, said Dr. Thomas Steinemann, clinical spokesperson for the American Academy of Ophthalmology.

(Note: Regular glasses or sunglasses aren’t enough, because they leave too many gaps around the eyes.)

But if you’re vaccinated or not in a high-risk situation, wearing goggles isn’t necessary.

While it’s still possible to get Covid-19 through the eyes, that scenario is less likely than getting it through your nose or mouth, Steinemann said.

He said if a significant number of people were getting coronavirus through their eyes, doctors would probably see more Covid-19 patients with conjunctivitis, also known as pink eye (though having pink eye doesn’t necessarily mean you have coronavirus).

The CDC does not recommend using plastic face shields for everyday activities or as a substitute for face masks. There are a few exceptions, such as for those who are hearing-impaired and rely on lip-reading or those who have physical or mental health conditions that would be exacerbated by wearing a face mask.

Face shields worn in addition to masks could provide an added layer of protection and can also help people stop touching their faces.

If someone must use a face shield without a mask, the CDC says the shield “should wrap around the sides of the wearer’s face and extend to below the chin. Disposable face shields should only be worn for a single use. Reusable face shields should be cleaned and disinfected after each use.”

No. In fact, Covid-19 has killed more people in one year than the flu did during the last five flu seasons combined.

During the 2019-2020 flu season, an estimated 22,000 people in the US died from the flu, according to the CDC.

With Covid-19, the first known US death was in February 2020. By January 27, more than 427,000 people had died, according to data from Johns Hopkins University. Covid-19 has now taken more than half a million US lives.

Yes. And the increased risk applies to cancer patients of all ages, the CDC says.

“Having cancer currently increases your risk of severe illness from COVID-19,” the CDC says. “At this time, it is not known whether having a history of cancer increases your risk.”

Researchers found that patients whose cancer was getting worse or spreading were more than five times more likely to die in a month if they caught Covid-19.

But there are steps cancer patients can take to stay as healthy as possible:

• Make sure you have at least a 30-day supply of your medications.
• Don’t delay any life-saving treatment or emergency care during this pandemic.
• Talk with your healthcare provider about your individual level of risk based on your condition, your treatment, and the level of transmission in your community.
• Don’t stop taking your medicines or alter your treatment plan without talking to your healthcare provider.
• Call your healthcare provider if you think you may have been exposed to the novel coronavirus.
• Read the CDC’s tips for preventing infections in cancer patients.

Technically it can, but HVAC (heating/ventilation/air conditioning) systems are not thought to be a significant factor in the spread of coronavirus.

Many modern air conditioning systems will either filter out or dilute the virus. Ventilation systems with highly effective filters are a key way to eliminate droplets from the air, said Harvard environmental health researcher Joseph Gardner Allen.

Filters are rated by a MERV system – their “minimum efficiency reporting value” that specifies their ability to trap tiny particles. The MERV ratings go from 1 to 20. The higher the number, the better the filtration.

HEPA filters have the highest MERV ratings, between 17 and 20. HEPA filters are used by hospitals to create sterile rooms for surgeries and to control infectious diseases. They’re able to remove 99.97% of dust, pollen, mold, bacteria and other airborne particles as small as 0.3 microns.

For context, this coronavirus is thought to be between 0.06 to 1.4 microns in size.

But “HEPA filtration is not always going to be feasible or practical,” Allen said. “But there are other filters that can do the job. What is recommended now by the standard setting body for HVAC is a MERV 13 filter.”

High-efficiency filters in the 13-to-16 MERV range are often used in hospitals, nursing homes, research labs and other places where filtration is important.

“If you’re an owner of a home, building or mall, you want to have someone to assess your system and install the largest MERV number filter the system can reliably handle without dropping the volume of air that runs through it,” advised Erin Bromage, an associate professor of biology at the University of Massachusetts Dartmouth.

“In addition, virtually all modern air conditioning systems in commercial buildings have a process called makeup air where they bring in air from outside and condition it and bring it inside,” Bromage said. “It’s worse in regards to energy, but the more outside air we bring in, the more dilution of the virus we have and then the safer you are.”

Asymptomatic describes a person who is infected but does not have symptoms. With Covid-19, asymptomatic carriers can still easily infect others without knowing it. So if you’re infected but don’t feel sick, you could still get others very sick.

Some medical professionals differentiate between truly asymptomatic carriers – those who don’t currently have and will never have symptoms – from “pre-symptomatic” carriers – those who don’t have symptoms now, but will get them later. But the general public often uses the term “asymptomatic” to describe both categories of infected people.

Regardless of which term you use, researchers have found that about half of coronavirus transmissions happen between people who don’t have any symptoms. And in some cases, people are more contagious before they start showing symptoms.

Unlike SARS and swine flu, the novel coronavirus is both highly contagious and especially deadly, CNN Chief Medical Correspondent Dr. Sanjay Gupta said.

“SARS was also a coronavirus, and it was a new virus at the time,” Gupta said. “In the end, we know that SARS ended up infecting 8,000 people around the world and causing around 800 deaths. So very high fatality rate, but it didn’t turn out to be very contagious.”

The swine flu, or H1N1, “was very contagious and infected some 60 million people in the United States alone within a year,” Gupta said. “But it was far less lethal than the flu even — like 1/3 as lethal as the flu.”

What makes the novel coronavirus different is that “this is both very contagious … and it appears to be far more lethal than the flu as well.”

The odds of transmitting coronavirus through sex hasn’t been thoroughly studied, though it has been found to exist in men’s semen.

But we do know Covid-19 is a highly contagious respiratory illness that can spread via saliva, coughs, sneezes, talking or breathing — with or without symptoms of illness.

So three Harvard physicians examined the likelihood of getting or giving Covid-19 during sex and made several recommendations.

For partners who haven’t been isolating together, they should wear masks and avoid kissing, the authors write.

In addition to wearing masks, people who have sex with partners outside of their home should also shower before and after; avoid sex acts that involve the oral transmission of bodily fluids; clean up the area afterward with soap or alcohol wipes to reduce their likelihood of infection.

Yes, some young adults have suffered strokes after getting coronavirus.

“The virus seems to be causing increased clotting in the large arteries, leading to severe stroke,” said Dr. Thomas Oxley, a neurosurgeon at Mount Sinai Health System in New York.

“Most of these patients have no past medical history and were at home with either mild symptoms (or in two cases, no symptoms) of Covid.”

Doctors say getting vaccinated is the best way to prevent coronavirus infection.

If you’re not vaccinated, it’s best to take the stairs if you can. But if you can’t, emergency room physician Dr. Leana Wen offers several tips:

• Wear a mask. Not only does wearing a mask reduce your risk of inhaling the virus — which can linger in the air for 8 minutes — it also helps reduce your chances of infecting others if you are an asymptomatic carrier.
• Use a tissue to push the elevator buttons. If you don’t have a tissue, use your elbow, then wash or disinfect that area when you can.
• Try to keep your distance from anyone else inside the elevator as much as possible.

For those not fully vaccinated, try to avoid public restrooms if you can, said microbiologist Ali Nouri, president of the Federation of American Scientists. But he acknowledged that’s not always possible: “Sometimes when you gotta go, you gotta go.”

Close contact with others is the most significant risk in a public restroom, Nouri said. So if there’s a single-person bathroom available that doesn’t have multiple stalls, using that might be best.

If you do use a multi-stall public restroom, Nouri offers the following tips:

• Don’t use your freshly washed hands to turn off the water with the germ-laden faucet handle. Instead, use a paper towel to turn off the water and open the bathroom door. Throw away the paper towel immediately afterward.
• Wear a face mask. “Masks are one of the most effective ways to stop human-to-human transmission,” Nouri said. “If people in a public bathroom are not wearing masks, think twice before going in.”
• If the restroom looks crowded, wait until it clears out, if you can. “You’re reducing the risk of inhaling aerosolized particles from other people,” Nouri said.

Yes — as long as you use the right kind of sanitizer and use it correctly.

Hand sanitizers “need to have at least 60% alcohol in them,” said Dr. William Schaffner, professor of preventative medicine and infectious disease at Vanderbilt University School of Medicine.

And don’t just put a little dollop in your hand and smear it around quickly.

“You’ve got to use enough and get it all over the surfaces,” Schaffner said. “Rub it all over your hands, between your fingers and on the back of your hands.”

But it’s always better to thoroughly wash your hands, if you’re able to.

“Alcohol is pretty effective at killing germs, but it doesn’t wash away stuff,” said Dr. John Williams, a virologist at the University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh.

“If somebody’s just sneezed into their hand, and their hand is covered with mucus, they would have to use a lot more alcohol to inactivate that bacteria or virus.”

“People can be contagious without symptoms. And in fact – a little bit strangely in this case — people tend to be the most contagious before they develop symptoms, if they’re going to develop symptoms,” CNN Chief Medical Correspondent Dr. Sanjay Gupta said.

“They call that the pre-symptomatic period. So people tend to have more virus at that point seemingly in their nose, in their mouth. This is even before they get sick. And they can be shedding that virus into the environment.”

Some people infected with coronavirus never get symptoms. But it’s easy for these asymptomatic carriers to infect others, said Anne Rimoin, an epidemiology professor at UCLA’s School of Public Health.

“When you speak, sometimes you’ll spit a little bit,” she said. “You’ll rub your nose. You’ll touch your mouth. You’ll rub your eyes.”

Health officials suggests people wear face masks while in public and when it’s difficult to stay 6 feet away from others.

A study published in The New England Journal of Medicine found that people with Type A blood have a higher risk of getting infected with coronavirus and developing severe symptoms, while people with Type O blood have a lower risk – but the study has caveats.

The researchers cannot say if blood type is a direct cause of the differences in susceptibility. It could be that genetic changes that affect someone’s risk also just happen to be linked with blood type, they said.

The study’s findings, while plausible, may mean very little for the average person, said Dr. Roy Silverstein, a hematologist and chairman of the department of medicine at the Medical College of Wisconsin.

“The absolute difference in risk is very small,” he said. “The risk reduction may be statistically significant, but it is a small change in actual risk. You never would tell somebody who was Type O that they were at smaller risk of infection.”

The bottom line: “All of us are susceptible to this virus,” said Dr. Maria Van Kerkhove, technical lead for the World Health Organization’s Covid-19 response.

“It’s probably safe if you’re not at home,” emergency physician Dr. Leana Wen said. She suggested leaving the windows open to improve ventilation and asking the cleaners to use your own cleaning supplies so they don’t bring items that have been in other people’s houses.

That’s “not a great idea,” said Dr. Joseph Vinetz, a professor of infectious diseases at Yale School of Medicine. “We have no evidence about that.”

“If there’s a metal piece in an N95 or surgical mask and even staples, you can’t microwave them,” he said. “It’ll blow up.”

To disinfect masks that you can’t wash, Vinetz recommends leaving them in a clean, safe place in your home for a few days. After that, it should no longer be infectious, as this coronavirus is known to survive on hard surfaces for only up to three days.

Doctors strongly recommend performing CPR when someone needs it.

You could be hundreds of times more likely to save that dying person’s life than you are to die from Covid-19 if you contract it after performing CPR, according to a report published by a group of Seattle emergency room physicians in the journal Circulation.

But it’s important to act quickly for CPR to be effective.

“The chance of survival goes down by 10% for every minute without CPR,” said Dr. Comilla Sasson, vice president for science and innovation in emergency cardiovascular care at the American Heart Association. “It’s a 10-minute window to death in many cases.”

If you’re not certified in CPR, performing chest compressions could also buy more time until help arrives. Bystanders should “provide high-quality chest compressions by pushing hard and fast in the middle of the victim’s chest, with minimal interruptions,” the American Heart Association said.

If you’re not sure how “fast” to do to those chest compressions, singing any of these popular songs will help you get the right rhythm.

It’s not the water you need to worry about. It’s how close you might get to other people.

“Properly maintained pool water will not be a source of spread of the virus. The chlorine that’s in it will inactivate the virus fairly quickly,” immunologist Erin Bromage said.

“The level of dilution that would happen in a pool or an ocean or a large freshwater body would not lead to enough virus to establish an infection. But when you do this, you need to just make sure that we’re maintaining an appropriate physical distance while swimming or sitting in a hot tub.”

That’s because it’s easy for infected people with no symptoms to spread the virus if they’re within 6 feet from each other. If you have an indoor pool or hot tub, even 6 feet might not be enough distance.

Randomly spraying open places is largely a waste of time, health experts say.

It can actually do more harm than good. “Spraying disinfectants can result in risks to the eyes, respiratory or skin irritation,” the World Health Organization said.

“Spraying or fumigation of outdoor spaces, such as streets or marketplaces, is also not recommended to kill the COVID-19 virus or other pathogens because disinfectant is inactivated by dirt and debris, and it is not feasible to manually clean and remove all organic matter from such spaces,” the WHO said.

“Moreover, spraying porous surfaces, such as sidewalks and unpaved walkways, would be even less effective.” Besides, the ground isn’t typically a source of infection, the WHO said.

And once the disinfectant wears off, an infected person could easily contaminate the surface again.

Any large gathering can increase the spread because this coronavirus is transmissible by talking or even just breathing. Carriers of the virus can be contagious even if they don’t have symptoms.

And when people are “shouting and cheering loudly, that does produce a lot of droplets and aerosolization that can spread the virus to people,” said Dr. James Phillips, a physician and assistant professor at George Washington University Hospital.

So doctors and officials say its important to get vaccinated or wear a face mask and try to keep your distance from others as much as possible.

“To date, there is no evidence that very high vitamin D levels are protective against COVID-19 and consequently medical guidance is that people should not be supplementing their vitamin D levels beyond those which are currently recommended by published medical advice,” wrote Robin May, director of the Institute of Microbiology and Infection at the University of Birmingham in the UK.

Vitamin D is important for healthy muscles, strong bones and a powerful immune system. The recommended daily dose of vitamin D for anyone over age 1 is 15 mcg/600?IU per day in the US. For anyone over 70 years of age in the US, the recommended daily intake goes up to 20 mcg/800?IU per day.

But too much vitamin D can lead to a toxic buildup of calcium in your blood that can cause confusion, disorientation, heart rhythm problems, bone pain, kidney damage and painful kidney stones.

“Viruses can live on surfaces and objects — including on money — although your chance of actually getting COVID-19 from cash is probably very low,” emergency medicine physician Dr. Leana Wen said.

The new coronavirus can live for up to 72 hours on stainless steel and plastic, up to 24 hours after landing on cardboard, and up to four hours after landing on copper, according to a study funded by the US National Institutes of Health.

So how do you protect yourself? To avoid touching cash or coins, use contactless methods of payment whenever possible, Wen said.

If you can’t use a contactless form of payment, credit cards and debit cards are much easier to clean and disinfect than cash. But remember that anyone who touches your credit card can also leave germs on it.

If you must use cash, “wash your hands well with soap and water” afterward, Wen said.

The same applies for anything else you touch that might have coronavirus on it. If you can’t wash your hands immediately, use hand sanitzier or disinfectant.

And since Covid-19 is a respiratory disease, make sure you avoid touching your face.

While some UV light devices are used for hospital disinfection, UV light only kills germs under very specific conditions — including certain irradiation dosages and exposure times, the World Health Organization said.

But UV light can also damage the body.

Two factors are required for UV light to destroy a virus: intensity and time. If the light is intense enough to break apart a virus in a short time, it’s going to be dangerous to people, said Donald Milton, a professor at the University of Maryland.

UVA and UVB light both damage the skin. UVC light is safer for skin, but it will damage tender tissue such as the eyes.

No. The US Food and Drug Administration says you don’t need to wash fresh produce with soap and water, but you should rinse it with plain water.

But it’s still important to wash your hands with soap and water frequently because we often touch our faces without realizing it.

You don’t have to worry about getting coronavirus by “eating” it, though. Even if coronavirus does get into your food, your stomach acid would kill it, said Dr. Angela Rasmussen, a virologist at Columbia University.

Coronavirus can stick to hair, said Dr. David Aronoff, director of the Division of Infectious Diseases at Vanderbilt University Medical Center.

Touching contaminated hair and then touching your mouth, eyes or nose could increase your risk of infection. “Like on the skin, this coronavirus is a transient hitchhiker that can be removed by washing,” Aronoff said.

But that doesn’t mean you have to wash the hair on your head multiple times a day, said dermatologist Dr. Hadley King.

That’s because “living hair attached to our scalps may be better protected by our natural oils that have some antimicrobial properties and may limit how well microbes can attach to the hair,” she said.

“If you are going out into areas that could possibly be contaminated with viral particles, then it would be reasonable to wash the hair daily during the pandemic. But it’s not the same as hand washing – the virus infects us through our mucosal surfaces. If your hair is not falling into your face or you’re not running your fingers through it, then there is less of a risk.”

If your hair does fall into your face, you may want to pull it back to minimize your risk, King said.

As for facial hair, “washing at least daily if not more frequently is wise, depending on how often they touch their face,” Aronoff said.

There have been some reports of animals infected with coronavirus — including two pets in New York and eight big cats at the Bronx Zoo.

Most of those infections came from contact with humans who had coronavirus, like a zoo employee who was an asymptomatic carrier.

But according to the CDC, there is no evidence animals play a significant role in spreading the virus to humans. Therefore, at this time, routine testing of animals for Covid-19 is not recommended.

As always, it’s best to wash your hands after touching an animal’s fur and before touching your face. And if your pet appears to be sick, call your veterinarian.

This “Contact tracing 101” article explains how contact tracing works, who can get hired, and how contact tracing has helped quash previous outbreaks.

But the US hasn’t been doing nearly enough contact tracing, experts say. Here’s why.

Hot water is best for killing bacteria and viruses in your laundry. But you don’t want to use that kind of scalding hot water on your skin.

Warm water is perfectly fine for washing your hands — as long as you wash them thoroughly (like this) and for at least 20 seconds. (To time yourself, you can hum the “Happy Birthday” song twice or sing a couple of verses from any of these hit songs from the past several decades.)

Cold water will also work, “but you have to make sure you work really vigorously to get a lather and get everything soapy and bubbly,” said chemist Bill Wuest, an associate professor at Emory University. To do that, you might need to sing “Happy Birthday” three times instead of twice.

“Warm water with soap gets a much better lather – more bubbles,” Wuest said. “It’s an indication that the soap is … trying to encapsulate the dirt and the bacteria and the viruses in them.”

Yes, you can use soap and water on surfaces just like you would on your hands to kill coronavirus. But don’t use water alone — that won’t really help.

The outer layer of the virus is made up of lipids, aka fat. Your goal is to break through that fatty barrier, forcing the virus’ guts to spill out and rendering it dead.

In other words, imagine coronavirus is a butter dish that you’re trying to clean.

“You try to wash your butter dish with water alone, but that butter is not coming off the dish,” said Dr. John Williams, chief of pediatric infectious diseases at UPMC Children’s Hospital of Pittsburgh.

“You need some soap to dissolve grease. So soap or alcohol are very, very effective against dissolving that greasy liquid coating of the virus.”

By cutting through the greasy barrier, Williams said, “it physically inactivates the virus so it can’t bind to and enter human cells anymore.”

Yes, coronavirus can live on the soles of shoes, but the risk of getting Covid-19 from shoes appears to be low.

A report published by the CDC highlighted a study from a hospital in Wuhan, China, where this coronavirus outbreak began.

The soles of medical workers’ shoes were swabbed and analyzed, and the study found that the virus was “widely distributed” on floors, computer mice, trash cans and door knobs. But it’s important to note the study was done in a hospital, where the virus was concentrated.

It’s still possible to pick up coronavirus on the bottoms of your shoes by running errands, but it’s unlikely you’ll get sick from it because people don’t often touch the soles of their shoes and then their faces. Because Covid-19 is a respiratory disease, the CDC advises wearing a mask while in public and washing your hands frequently– the correct way.

If you have small children who crawl or regularly touch the floor, it’s a good idea to take your shoes off as soon you get home to prevent coronavirus or bacteria from spreading on the floors.

There’s no evidence that coronavirus can be transmitted through food, the CDC says.

Even if coronavirus does get into your food, your stomach acid would kill it, said Dr. Angela Rasmussen, a virologist at Columbia University.

“When you eat any kind of food, whether it be hot or cold, that food is going to go straight down into your stomach, where there’s a high acidity, low-pH environment that will inactivate the virus,” she said.

But it’s a good idea to disinfect the takeout containers, CNN Chief Medical Correspondent Dr. Sanjay Gupta said. Coronavirus is a respiratory virus, and it’s easy to touch your face without realizing it.

If you don’t have disinfecting wipes, use your own plates or bowls to serve the food. Just make sure to wash your hands after transferring food from the containers.

“There is no evidence that COVID-19 can be spread to humans through the use of pools and hot tubs,” the CDC says.

“Proper operation, maintenance, and disinfection (e.g., with chlorine and bromine) of pools and hot tubs should remove or inactivate the virus that causes COVID-19.”

But health officials still advise staying at least 6 feet away from others because COVID-19 is a respiratory disease. In other words, you probably won’t get coronavirus from the water, but you could get coronavirus from someone close to you in the water.

As for drinking water, doctors say you don’t need to worry about coronavirus in the tap water because most municipal drinking water systems should remove or inactivate the virus.

“To date there has been no information nor evidence to suggest that the new coronavirus could be transmitted by mosquitoes,” the World Health Organization says. There’s also no evidence so far suggesting flies can spread coronavirus.

“That’s a bad idea,” said Dr. Colleen Kraft, an infectious diseases professor at Emory University School of Medicine. “It could definitely kill you.”

Former President Donald Trump wondered aloud during a press conference whether there’s “a way we can do something like that, by injection inside or almost a cleaning.”

But the Reckitt Benckiser Group, which produces Lysol cleaning products, said “under no circumstance” should disinfectants be put into the human body.

“I don’t think you need to,” CNN Chief Medical Correspondent Dr. Sanjay Gupta said.

Coronavirus can stay alive for up to three days on stainless steel and plastic. But clothing “is probably more like cardboard — it’s more absorbent, so the virus is unlikely to stay and last that long,” Gupta said.

While coronavirus can stay alive on cardboard for up to 24 hours, viruses generally don’t stick well on surfaces that are in motion.

“If you look at how viruses move through air, they kind of want to move around objects,” Gupta said. “They don’t want to necessarily land on objects. So if you’re moving as human body through the air … (it’s) unlikely to stick to your clothes.”

Not necessarily. Antibodies are a body’s response to bacteria or viruses. But it’s not clear whether having antibodies means you have long-term protection from getting reinfected.

“The thing we don’t know yet is what is the relationship between the level of antibody and the degree of your protection,” Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told Snapchat’s “Good Luck America” show.

“So you may be positive for an antibody, but not enough to protect you.”

There’s also a risk that some antibody tests might confuse the novel coronavirus with other coronaviruses, like the ones that cause the common cold.

Please don’t. The CDC advises using hand sanitizer that contains at least 60% alcohol.

Vodka typically contains between 35% and 46% percent alcohol.

If the stores are out of hand sanitizer and you want to make your own, the Nebraska Medical Center offers this recipe:

What you’ll need:

• 2/3 cup 91% isopropyl alcohol (rubbing alcohol)
• 1/3 cup aloe vera gel
• Mixing bowl
• Spoon or something for whisking
• Small container, such as a 3-oz. travel bottle
• Optional: essential oil to give your hand sanitizer a fragrance

Directions:
In a mixing bowl, stir isopropyl alcohol and aloe vera gel together until well blended.
Add 8-10 drops of scented essential oil (optional, but nice). Stir.
Pour the homemade hand sanitizer into an empty container and seal. Write “hand sanitizer” on a piece of masking tape and attach to the bottle.

This is not a good time to be vaping or smoking anything, including weed.

“Vaping affects your lungs at every level. It affects the immune function in your nasal cavity by affecting cilia, which push foreign things out,” said Prof. Stanton Glantz, director of the Center for Tobacco Research Control and Education at University of California San Francisco.

When you vape, “the ability of your upper airways to clear viruses is compromised,” Glantz said.

Tobacco smokers are at especially high risk. In a study from China, where the first Covid-19 outbreak occurred, smokers were 14 times more likely to develop severe complications than non-smokers.

Even occasionally smoking marijuana can put you at greater risk.

“What happens to your airways when you smoke cannabis is that it causes some degree of inflammation, very similar to bronchitis, very similar to the type of inflammation that cigarette smoking can cause,” said pulmonologist Dr. Albert Rizzo, chief medical officer for the American Lung Association.

“Now you have some airway inflammation, and you get an infection on top of it. So yes, your chance of getting more complications is there.”

Coronavirus isn’t just infecting young people. It’s killing young, healthy people as well.

We’ve reported many stories about young people getting severely sick with or dying from coronavirus.

Dimitri Mitchell, 18, admits he had a “false sense of security.” But he was later hospitalized with coronavirus and now wants everyone to take it seriously.

“I just want to make sure everybody knows that no matter what their age is, it can seriously affect them. And it can seriously mess them up, like it messed me up,” the Iowa teen said.

“Four days in, the really bad symptoms started coming along. I started having really bad outbreaks, like sweating, and my eyes were really watery. I was getting warmer and warmer, and I was super fatigued. … I would start experiencing the worst headaches I’ve ever felt in my life. They were absolutely horrible.”

Eventually, the teen had to be hospitalized. His mother said she worried he might “fall asleep and never wake up.”

Mitchell is now recovering, but has suffered from long-term effects.

“I just hope everybody’s responsible, because it’s nothing to joke about,” he said. “It’s a real problem, and I want everybody to make sure they’re following social distancing guidelines and the group limits. And just listen to all the rules and precautions and stay up to date with the news and make sure they’re informed.”

No. That’s just a hoax going around the internet.

“The theory that 5G might compromise the immune system and thus enable people to get sick from corona is based on nothing,” said Eric van Rongen, chairman of the International Commission on Non-Ionizing Radiation Protection (ICNIRP).

Learn more about how 5G really works and why this hoax makes no sense.

Ideally, you should limit your children’s potential exposures to coronavirus and work out the safest plan possible with your ex.

The problem: Some state and county family courts might be closed, or open only for emergencies involving abuse or endangerment. So it might be difficult to formally modify pre-existing custody agreements.

But some states may be offering some flexibility during the pandemic. And there may be creative solutions, such as spending more time with one parent now in exchange for extra time with the other parent after the pandemic ends.

Up to three days, depending on the surface. According to a study funded by the US National Institutes of Health:

• The novel coronavirus is viable up to 72 hours after being placed on stainless steel and plastic.
• It was viable up to four hours after being placed on copper, and up to 24 hours after being put on cardboard.
• In aerosols, it was viable for three hours.

Some cases of coronavirus do lead to pneumonia. But the pneumonia vaccine won’t help.

“Vaccines against pneumonia, such as pneumococcal vaccine and Haemophilus influenza type B (Hib) vaccine, only help protect people from these specific bacterial infections,” according to Harvard Medical School.

“They do not protect against any coronavirus pneumonia.”

In some cases, health care workers haven’t had enough protective gear to handle the volume of Covid-19 patients.

Some have resorted to using plastic report covers as masks. The CDC said medical providers might have to use expired masks or reuse them between multiple patients.

But it’s not just subpar protective gear that puts medical workers at risk. It’s also the amount of virus they’re exposed to.

“The viral load — the amount of virus – does determine the severity of your illness,” emergency medicine physician Dr. Leana Wen said. “So that could happen in the case of health care workers who are exposed to a lot more Covid-19 as a result of their work — that they get more severely ill.”

In one study, about 4 in 5 people with confirmed coronavirus in China were likely infected by people who didn’t know they had it, according to research published in the journal “Science” last year.

“These findings explain the rapid geographic spread of (coronavirus) and indicate containment of this virus will be particularly challenging,” researchers wrote.

In March 2020, the CDC said almost half of the 712 people with coronavirus who were on the Diamond Princess cruise ship didn’t have any symptoms when they tested positive.

Other studies have suggested 25% to 50% of coronavirus carriers don’t have symptoms.

It may be difficult to know whether your loved one has coronavirus or another illness. So it’s critical to play it safe and not infect yourself and, in turn, others. The CDC suggests:

• Giving the sick person their own room to stay in, if possible. Keep the door closed.
• Having only one person serve as the caretaker.
• Asking the sick person to wear a face mask, if it doesn’t cause breathing problems. It’s a good idea for the caretaker to also wear a secure face mask.

Fatigue, fever, dry cough, difficulty breathing and the loss of taste or smell are some of the symptoms of Covid-19.

Symptoms can appear anywhere from 2 days to 2 weeks after exposure, the CDC says. But some people get no symptoms at all and can infect others without knowing it.

The illness varies in its severity. And while many people can recover at home just fine, some — including young, previously healthy adults — are suffering long-term symptoms.

Don’t visit family members with suspected illness – connect with them virtually. If that person lives with you, limit contact with them and avoid using the same bathroom or bedroom if possible, the CDC advises.

If the person been diagnosed, he or she might be able to recover at home in isolation. Separate yourself as much as possible from your infected family member and keep animals away, too. Continue to use separate restrooms and regularly disinfect them.

Stock up on groceries and household supplies for them while they can’t travel outside and minimize trips to stores. Wash your hands frequently and avoid sharing personal items with the infected person.

If you think you’re developing symptoms, stay home and call your physician.

Yes, you can make both at home.

“Unexpired household bleach will be effective against coronaviruses when properly diluted” if you’re trying to kill coronavirus on a non-porous surface, the CDC said.

The CDC’s recipe calls for diluting 5 tablespoons (or ? cup) of bleach per gallon of water, or 4 teaspoons of bleach per quart of water.

You can also make your own hand sanitizer. The Nebraska Medical Center – famous for its biocontainment unit and treatment of Ebola patients – offers this recipe:

What you’ll need:

• 2/3 cup 91% isopropyl alcohol (rubbing alcohol)
• 1/3 cup aloe vera gel
• Mixing bowl
• Spoon or something for whisking
• Small container, such as a 3 oz. travel bottle
• Optional: essential oil to give your hand sanitizer a fragrance

Directions:
In a mixing bowl, stir isopropyl alcohol and aloe vera gel together until well blended.
Add 8-10 drops of scented essential oil (optional, but nice). Stir.
Pour the homemade hand sanitizer into an empty container and seal.
Write “hand sanitizer” on a piece of masking tape and attach to the bottle.

An employee can be fired if they don’t show up to work and don’t have sick leave that would cover the absence, says Krista Slosburg, an employment attorney at Stokes Lawrence in Seattle.

But there are exceptions. Employers who make workers with Covid-19 come in may be violating Occupational Safety and Health Administration [OSHA] regulations, said Donna Ballman, who heads an employee advocacy law firm in Florida.

If you work in a city or state that requires sick leave and you use it, you can‘t be terminated or disciplined.

But there is no federal mandate that requires companies to offer paid sick leave, and almost a quarter of all US workers don’t get it, according to 2019 government data. Some state and local governments have passed laws that require companies to offer paid sick leave.

The Family and Medical Leave Act (FMLA) can sometimes protect a worker’s job in the event they get sick, but it won’t guarantee they get paid while they’re out.

Employee advocates urge businesses to consider the special circumstances of the Covid-19, and some already have

Yes, managers can.

The Society for Human Resource Management recommends companies “actively encourage sick employees to stay home, send symptomatic employees home until they are able to return to work safely, and require employees returning from high-risk areas to telework during the incubation period (of 14 days).”

If a manager feels an employee’s illness poses a direct threat to colleagues’ safety, the manager may be able to insist the employee be evaluated by a doctor, said Alka Ramchandani-Raj, an attorney specializing in workplace safety.

Since Covid-19 is a respiratory disease, many airlines require passengers to wear face masks during the flight, except for while eating or drinking.

Health experts suggest eating, drinking and using the restroom before getting on the plane, to eliminate the need to take off your mask or go into a cramped lavatory on board.

And always be mindful of where your hands have been, travel medicine specialist Dr. Richard Dawood said.

Airport handrails, door handles and airplane lavatory levers are notoriously dirty.

“It is OK to touch these things as long as you then wash or sanitize your hands before contaminating your face, touching or handling food,” Dawood said.

“Hand sanitizers are great. So are antiseptic hand wipes, which you can also use to wipe down armrests, remote controls at your seat and your tray table.”

No. Those products work on surfaces but can be dangerous to your body.

There are some chemical disinfectants, including bleach, 75% ethanol, peracetic acid and chloroform, that may kill the virus on surfaces.

But if the virus is already in your body, putting those substances on your skin or under your nose won’t kill it, the World Health Organization says. And those chemicals can harm you.

There’s no evidence from the outbreak that eating garlic, sipping water every 15 minutes or taking vitamin C will protect people from the new coronavirus. Same goes for using essential oils or colloidal silver.

Experts said cuts in federal funding for public health and problems with early testing forced the US to play catch-up.

Problems with public health infrastructure: Two years ago, the CDC stopped funding epidemic prevention activities in 39 countries, including China. This happened because the Trump administration refused to allocate money to a program that started during the 2014 Ebola outbreak.

Former CDC director Dr. Tom Frieden warned that move “would significantly increase the chance an epidemic will spread without our knowledge and endanger lives in our country and around the world.”

Problems with the testing: Malfunctions, shortages and delays in availability have all contributed to the slowdown.

In the first few weeks of the outbreak in the US, the CDC was the only facility in the country that could confirm test results — even though a World Health Organization test became available around the same time.

Some test kits that were sent around the country were flawed — a move that put the US behind about “four to five weeks,” says Dr. Rob Davidson, executive director of the Committee to Protect Medicare.

No antibiotics are effective against Covid-19 because the disease is caused by a viral infection, not a bacterial infection.

“However, if you are hospitalized for the [coronavirus], you may receive antibiotics because bacterial co-infection is possible,” the World Health Organization says.

There is no known cure for the novel coronavirus.

No. There are some interesting coincidences in the 1981 fiction novel, which says “a severe pneumonia-like illness will spread around the globe” around the year 2020. Modern editions of the book call the biological strain “Wuhan-400,” and the current coronavirus outbreak started in Wuhan, China.

But there are important differences between the book and reality. The original version of the book called the strain the “Gorki-400,” in reference to a Russian locality, before it was later changed to the “Wuhan-400.” In the book, the virus was man-made, while scientists believe the novel coronavirus started in animals and jumped to humans. And in the book, the virus had a 100% mortality rate. Early estimates of the mortality rate for this coronavirus outbreak range from 2-4%.

No. “The new coronavirus cannot be transmitted through goods manufactured in China or any country reporting Covid-19 cases,” the World Health Organization says.

“Even though the new coronavirus can stay on surfaces for a few hours or up to several days (depending on the type of surface), it is very unlikely that the virus will persist on a surface after being moved, travelled, and exposed to different conditions and temperatures,” WHO said.

Hand dryers can’t kill the virus, the World Health Organization said.

WHO also said UV lamps shouldn’t be used to sterilize hands or other areas of the body because the radiation can irritate skin.