Corona Virus Q&A

As we all are coming to grips with this new reality, here are some of your most commonly asked questions answered by the experts.

What percentage of people with coronavirus don’t have symptoms? Are they still contagious?

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.”

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

In the US, “I think it could be as many as 1 in 3 walking around asymptomatic right now,” said New Jersey primary care physician Dr. Alex Salerno.

“We have tested some patients that have known exposure to COVID (coronavirus disease). They did not have temperature. Their pulse/(oxygen) was OK.”

Aside from social distancing and frequent hand washing, Salerno said more testing of people without symptoms is essential.

“We test people, we get a positive test … we isolate them, and we separate them from the people who are not positive,” Salerno said. If more asymptomatic people got tested, “we could get people back to work safely.”

But there’s not nearly enough tests in the US for everyone who wants one, due to shortages, delays and faulty test kits.

Why worry about coronavirus when the flu kills many more people?

The novel coronavirus is dangerous for several reasons, even if the number of deaths haven’t matched that of the flu.

The first US case of coronavirus was reported in January, and the first US death from coronavirus was reported in late February. By March 26, the US had more than 78,000 cases of coronavirus, and at least 1,135 people have died.

Since this flu season started October 1, more than 23,000 Americans have died from the flu, according to CDC estimates. Nationwide, the flu has infected at least 34 million people between October and mid-March.

But here are key differences when comparing the flu vs. coronavirus:

  • The CDC estimates for the flu go back to October 2019. But the first US case of coronavirus didn’t emerge until several months later.
  • Coronavirus is twice as contagious as the flu. Research indicates a person with the flu infects an average of 1.28 other people, CNN Chief Medical Correspondent Dr. Sanjay Gupta said. But with coronavirus, “it’s likely between two and three” other people.
  • Coronavirus infections have a “very high mortality rate – one in six – among people who are over 80 and people with underlying chronic disease,” epidemiologist Dr. Abdul El-Sayed said.
  • People with coronavirus might not get symptoms for 14 days, and some get no symptoms at all. But during that time, they’re still contagious and can infect others unknowingly.
  • A vaccine is available for the flu, but no vaccine is available for coronavirus. Experts say the number of flu deaths could be drastically reduced if more people got their flu shots. But about half of Americans don’t get vaccinated, including most children who die from the flu.

Can coronavirus spread through water, like in a pool or hot tub?

While many gyms are closed, some members wonder if it’ll be safe to get in the water once facilities re-open.

“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.”

For now, health officials still advise staying at least 6 feet away from others, since COVID-19 is a respiratory infection.

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.

Can high or low temperatures kill coronavirus?

“Generally coronaviruses survive for shorter periods of time at higher temperatures and higher humidity than in cooler or dryer environments. However, we don’t have direct data for this virus, nor do we have direct data for a temperature-based cutoff for inactivation at this point,” the CDC says.

“The necessary temperature would also be based on the materials of the surface, the environment, etc.”

President Donald Trump suggested this coronavirus could subside by the warmer summer months, but scientists say it’s too early to tell. And the fact that coronavirus is spreading in the Southern Hemisphere during its summer months indicates this strain might not succumb to warmer temperatures.

“The short answer is that while we may expect modest declines in the contagiousness of (novel coronavirus) in warmer, wetter weather and perhaps with the closing of schools … it is not reasonable to expect these declines alone to slow transmission enough to make a big dent,” wrote Dr. Marc Lipsitch, director of the Center for Communicable Disease Dynamics at Harvard’s T.H. Chan School of Public Health.

Can mosquitoes transmit coronavirus?

No. “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.

“The new coronavirus is a respiratory virus which spreads primarily through droplets generated when an infected person coughs or sneezes, or through droplets of saliva or discharge from the nose.”

Is it safe to get takeout from restaurants?

Yes, but you may want to wipe down the packaging and containers, just in case.

There’s no evidence to suggest coronavirus is transmitted through food, the CDC says. It’s generally spread through respiratory droplets.

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

How long will we have to keep social distancing?

Probably for several months. But you might have to do it “over and over again,” since the outbreak could come in waves.

Research by the Imperial College in Great Britain “would suggest you have to institute these kinds of measures for five months, very vigorously,” said Dr. Celine Gounder, an infectious disease specialist at Bellevue Hospital Center.

“And then you may be able to relax for a period. And then you would re-institute as the cases go up again. But we’re basically looking at doing this over and over and over again, even after a five-month period of strict social distancing, in order to curb cases until we have a vaccine.”

Health officials say we’re at least a year away from the first publicly available coronavirus vaccine. In the meantime, they say everyone should avoid large crowds and stay at least 6 feet away from others.

How long does coronavirus stay “alive” on surfaces?

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

  • The new 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 remained viable for three hours.

Is coronavirus more contagious than the flu?


Research indicates a person with the flu infects about 1.28 other people, on average, CNN Chief Medical Correspondent Dr. Sanjay Gupta said.

But with the novel coronavirus, he said, “it’s likely between two and three” other people.

What are the symptoms?

Fever, dry cough and difficulty breathing are hallmarks of coronavirus.

Symptoms may appear anywhere from 2 days to 2 weeks after exposure, the CDC says, though some patients haven’t shown symptoms at all.

The illness varies in its severity, and many patients can recover at home in isolation.

Older adults — ages 60 and older — and people with severe chronic illness are more likely to get seriously sick from the coronavirus.

Learn more about the difference between flu, coronavirus and allergy symptoms here.

How does it spread?

It primarily spreads between people through respiratory droplets — think coughs, sneezes, spittle.

You can also get coronavirus by touching infected surfaces, then touching your mouth, eyes or nose.

Learn how to not touch your face here.

How can someone pass along coronavirus when asymptomatic? If not sneezing or coughing, how can they infect others?

It’s easy for asymptomatic people with coronavirus to spread the illness, said Dr. Anne Rimoin, an epidemiology professor at UCLA’s School of Public Health.

“Certainly when you speak, sometimes you’ll spit a little bit,” Rimoin said. “You’ll rub your nose. You’ll touch your mouth. You’ll rub your eyes. And then you’ll touch other surfaces, and then you will be spreading virus if you are infected and shedding asymptomatically.”

Doctors stress that the best way to prevent getting coronavirus is not by wearing face masks, since they often cause more harm than good.

Instead, people should wash their hands with soap and water frequently for at least 20 seconds and stop touching their faces – which is harder than it sounds.

Can coronavirus go through skin and into the body?

“It may be possible that a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes, but this is not thought to be the main way the virus spreads,” the CDC says.

More often than not, people get coronavirus through respiratory droplets produced when an infected person coughs or sneezes.

“These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs,” the CDC says.

How long is someone contagious after getting coronavirus?

It varies. Decisions about when a person can be released from isolation are made on a case-by-case basis.

The Centers for Disease Control and Prevention issued guidelines for when it is OK to release someone from isolation. They include meeting all of these requirements:

  • The patient is free from fever without the use of fever-reducing medications.
  • The patient is no longer showing symptoms, including cough.
  • The patient has tested negative on at least two consecutive respiratory specimens collected at least 24 hours apart.

“Someone who has been released from isolation is not considered to pose a risk of infection to others,” the CDC says.

No one from my family has been exposed to the virus, and no one is sick. Can we get together for a family dinner? There are 10 of us, ages 4 to 88.

No one can say for sure that they haven’t been exposed to the virus. Some carriers of coronavirus don’t have any symptoms at all. But they can still pass on the virus without knowing it.

“We now know that asymptomatic transmission likely (plays) an important role in spreading this virus,” said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota.

He said it’s “absolutely clear” that asymptomatic infection “surely can fuel a pandemic like this in a way that’s going to make it very difficult to control.”

Read more: How can people spread coronavirus if they don’t have any symptoms?

Infectious disease experts say those older than 60 are at much higher risk of getting seriously ill if they’re exposed to coronavirus.

If you must socialize, it’s important to stay at least 6 feet away from others. Do not hug or kiss, wash your hands often for at least 20 seconds, and do not touch your face.

What exactly does ‘older’ adults mean? What is the age threshold?

The CDC says “older adults“ and people with serious chronic medical conditions “are at higher risk of getting very sick from this illness.”

Anyone over 60 and those with underlying health problems should try to avoid places with large crowds – such as movie theaters, busy malls and even religious services, infectious disease experts say.

“This ought to be top of mind for people over 60, and those with underlying health problems,” said Dr. William Schaffner, a Vanderbilt University professor and longtime CDC adviser.

But why is age 60 often used as a threshold for those who need to be extra cautious?

“(The) average age of death for people from coronavirus is 80. Average age of people who need medical attention is age 60,” US Surgeon General Jerome Adams said.

Read more about what adults 60 and older should do to prevent coronavirus.

Are kids more at risk?

“Younger people, thankfully, seem to be insulated to some extent to protect (them) from getting particularly sick from this,” said CNN Chief Medical Correspondent Dr. Sanjay Gupta. “We don’t know entirely why.”

But while children might have mild to no symptoms with coronavirus, they can still get others sick. “They can still carry the virus in their bodies,” Gupta said. “They could potentially still shed the virus and be a source of infection.”

Like everyone else, children should wash their hands frequently for at least 20 seconds, stay at least 6 feet away from anyone coughing or sneezing, and stop touching their faces – which is a lot harder than it sounds.

Is coronavirus especially harmful for pregnant women?

Long story short: There’s not enough data yet, considering this coronavirus just emerged in humans a few months ago.

The vulnerability of “older adults” has been well documented, but researchers “do not have information from published scientific reports about susceptibility of pregnant women” to this coronavirus, the CDC says.

“Adverse infant outcomes” like premature births have been reported among infants born to mothers who’ve tested positive for coronavirus during pregnancy, the CDC says. But it’s not clear if these outcomes were related to maternal infection, so the risk is unknown.

What can I do if my loved one suspects they have coronavirus?

Don’t visit family members with suspected illness – keep up with them virtually. If that loved one lives with you, limit contact with them and avoid using the same bathroom or bedroom, the CDC advises.

If they’ve been diagnosed, they may 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 with EPA-approved products.

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

Should I disinfect my groceries? If so, how?

“I would suggest wiping down external surfaces of canned or wrapped foods,” said Dr. Celine Gounder, an infectious disease specialist at Bellevue Hospital Center.

“You should be washing your vegetables (and) produce anyway,” she said. “But I think making sure you sanitize your hands, wash your hands after you do all that – after you unpack all your groceries – is also a key step.”

Do I need to isolate myself if I’m not diagnosed?

It depends.

Adults 60 and older and people with severe chronic illnesses are more likely to get very sick if they’re infected with Covid-19, so the CDC recommends those people stay at home as much as possible if they live in communities where there are outbreaks.

Some communities, cities and even countries have issued wide quarantines to contain the virus, but if you don’t live in one of those areas, use caution when going in public. Avoid crowds and poorly ventilated buildings, and frequently wash your hands before, during and after your trip out.

If you suspect you’re sick, though, or have recently returned from an area where an outbreak has been reported, stay home.

Should I avoid public transportation?

If you rely on public transportation, use caution. If you’re sick or live in an area where an outbreak has been reported, avoid it.

Mass transit could increase your risk of exposure to coronavirus. Luckily, transit systems are upping their cleaning regimens — notably the New York subway system.

Dr. Robyn Gershon, a professor of epidemiology at New York University’s School of Public Health, has some tips: When you ride a bus or subway, sneeze or cough into your elbow. Use a tissue to hold onto a pole. Avoid touching your face while you’re riding, and use hand sanitizer if you have it while you’re commuting.

Again, wash your hands before, during and after your trip.

Should I go to work?

If you can, you should stay home from work when you’re sick, whether or not you have coronavirus.

Many companies are increasingly flexible with work from home policies. If your company is allowing employees to work from home, consider it. Some companies have enforced working from home.

If you must go into work, maintain 6 feet of distance from your colleagues, wash your hands frequently and practice good respiratory etiquette by coughing or sneezing into your elbow.

Avoid handshakes, switch in-person meetings to teleconferences and disinfect your workspace with EPA-approved products at the start of your shift.

If traveling on a plane, how do I stay safe?

It’s not the cabin air you need to worry about. It’s keeping your hands clean.

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.”

Since a plane’s cabin keeps circulating air, will I get sick if another passenger is sick?

Most viruses don’t spread easily on airplanes because of how the air circulates and is filtered, the CDC says.

Modern commercial jets recirculate 10-50% of the air in the cabin, mixed with outside air. “The recirculated air passes through a series of filters 20-30 times per hour,” the CDC says.

“Furthermore, air generally circulates in defined areas within the aircraft, thus limiting the radius of distribution of pathogens spread by small-particle aerosols. As a result, the cabin air environment is not conducive to the spread of most infectious diseases.”

Still, try to avoid contact with anyone sneezing or coughing. And if you’re feeling sick, cover your entire mouth and nose with the inside of your elbow when you cough or sneeze.

What do I do if I think I’m sick?

Stay home. Call your doctor to talk about your symptoms and let them know you’re coming for an appointment so they can prepare for your visit, the CDC says.

Only a Covid-19 test can diagnose you with the virus, but if you suspect you have it, isolate yourself at home. Limit close contact with other people and animals you live with – the CDC recommends keeping 6 feet of distance.

Many patients with coronavirus are able to recover at home. If you’ve been diagnosed and your illness is worsening, seek medical attention promptly. You may need to be monitored in a hospital.

Ask your physician to call the local or state health department, too, so they’re aware that you’re being monitored for the virus.

If infected with coronavirus, can you survive it and recover?

Absolutely. The vast majority of people with coronavirus survive.

The director of the National Institute of Allergy and Infectious Diseases has estimated the death rate is “about 2%.”

How long does it take to recover?

“It takes anything up to six weeks to recover from this disease,” said Dr. Michael Ryan of the World Health Organization.

“People who suffer very severe illness can take months to recover from the illness.”

Recovery is often marked by a patient no longer showing symptoms and having two consecutive negative tests at least one day apart, Ryan said. But there is no known cure for the novel coronavirus.

After recovering from coronavirus, does the recovered patient have immunity to the virus?

It’s too early to know for sure. But other coronaviruses, like ones that cause the common cold, might give us clues.

With “common cold coronaviruses, you don’t actually have immunity that lasts for very long, and so we don’t know the answer with this specific coronavirus,” said Dr. Celine Gounder, a professor of medicine and infectious diseases at the New York University School of Medicine.

“That’s actually going to be one of the challenges with designing a vaccine is how do you actually cause the immunity to last long enough to protect you.”

Can heat kill the coronavirus?

Hand dryers can’t kill the virus, according to WHO. The organization also says that UV lamps shouldn’t be used to sterilize hands or other areas of the body because the radiation can irritate skin.

Drinking hot water or taking hot baths won’t kill it, either.

President Donald Trump has previously suggested that heat might kill the virus, and as a result, the current outbreak could dissipate by summer.

But public health experts say there’s no way to know this.