What it means to be at ‘high risk’ for the coronavirus

Some people who contract the virus may only develop a runny nose, but for others it could become life-threatening, a local doctor explains.

Health officials said this week that a second person in Massachusetts has tested positive for the the novel coronavirus, called COVID-19, bringing the number of reported cases in New England to five.

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Still, officials say the risk to the public from the virus remains low in Massachusetts.

Six people have died from the novel respiratory illness in the United States, with 15 states across the country reporting cases. U.S. Centers for Disease Control and Prevention officials have warned that it is only a matter of time before the virus outbreak, declared by the World Health Organization as a “public health emergency of international concern,” spreads more widely in the U.S.

The virus, which first emerged in December, comes from the coronavirus family, which includes strains responsible for everything from the common cold to those that cause much more severe illnesses like severe acute respiratory syndrome (SARS). Like the flu, it is spread through respiratory secretions — droplets produced when someone sneezes or coughs — and it causes symptoms including fever, cough, and shortness of breath. Symptoms, which range from mild to severe, can appear anywhere between two and 14 days after exposure.


For the general American public, the CDC says, the current risk for the virus is still considered low.

“The potential public health threat posed by COVID-19 is very high, to the United States and globally,” the CDC states of the risk assessment for the virus. “At this time, however, most people in the United States will have little immediate risk of exposure to this virus. This virus is NOT currently spreading widely in the United States. However, it is important to note that current global circumstances suggest it is likely that this virus will cause a pandemic. This is a rapidly evolving situation and the risk assessment will be updated as needed.”


There are elements that raise an individual’s risk for contracting COVID-19 and for developing more serious illness from the virus. To learn more, we spoke with Dr. Erica Shenoy, associate chief of the Infection Control Unit at Massachusetts General Hospital.

What are the risk factors for exposure to the virus?  

An almost empty subway train in Milan, Italy.

The people at highest risk of contracting the virus are those who have had close contact with someone with a confirmed case of coronavirus, Shenoy said.

“That would be if there is a case identified and we have individuals who are roommates or close contacts,” she said. “Those people are at high risk because they have a known exposure.”


Outside of those “known exposures” to the virus, there are parts of the world where there is widespread transmission of coronavirus in the community: China, Iran, Italy, Japan, and South Korea. In places where there is widespread transmission in the community, just being out and about in those areas would put you at risk, and increases your level of risk, of exposure to the virus, Shenoy said.

The CDC is advising that travelers avoid all non-essential travel to China, Iran, Italy, Japan, and South Korea.

What increases your risk of developing severe illness from coronavirus?

Massachusetts Gov. Charlie Baker listens during a press conference on the coronavirus on Monday. State officials say the risk remains low in Massachusetts.


Not everyone who is exposed to the coronavirus gets sick, Shenoy said.

“That’s true pretty much across the board,” she said of viruses. “We may be exposed to the flu many times a day, and, for many reasons, we may not get the flu. That could be because you’re vaccinated or whatever. Similarly with coronavirus, there will be people who are exposed who do not get disease.”

The people who are exposed and develop an infection can also develop a wide range of manifestations of the symptoms.

“From zero symptoms, feeling a little achy, feeling tired, maybe a runny nose, then maybe developing a fever, maybe having a cough,” Shenoy said. “And then at the very kind of extreme end, there will be people who have severe disease.”


On the severe end, the coronavirus can cause pneumonia or comprise a patient’s respiration to the point that they need a ventilator. But Shenoy said so far it appears that only a small portion of the total population of cases develop severe disease from the virus.

“For example, of all the people who present to the hospital it looks like maybe 25 percent or so might go to an ICU and a smaller portion of those will need a ventilator,” she said. “But that is very much concentrated in individuals who are either older — so extreme age — and who have underlying co-morbidities.”

Risk picks up for people in their 60s and 70s and older, she said, similar to how the flu can be more dangerous to people who are older. Heart disease, lung disease, diabetes, or other conditions resulting in a weaker immune system may also put patients at higher risk for more severe complications.

“If you took two individuals and one of them has those underlying diseases or is older compared to someone without them, you might expect — and again this is the beginning of this outbreak so we’re learning as we go  — that the person who has those underlying conditions or who is older is less better able to handle the infection and therefore could have severe disease,” Shenoy said.

Most of the studies done so far on coronavirus have been on the outbreak in China, she said.

“We don’t know how the case fatality rate in a large population here in the United States would differ, but I think the general principle of older individuals and those who have underlying health conditions would be at higher risk of developing severe disease if they have exposure,” Shenoy said.

What precautions should you take if you’re at higher risk?

Travelers apply hand sanitizer at Los Angeles International Airport.

If you’re at increased risk of developing more severe illness, Shenoy advised heeding the CDC warnings about not traveling to areas where there is widespread community transmission and even considering whether or not you should be traveling.

“As things evolve here and if we have widespread community transmission, then I think they’re going to do all the things that we’re already telling people to do, which is you make sure that you avoid people who are ill, you do a lot of hand-washing or using hand sanitizer,” Shenoy said. “If you develop illness, you call your provider and then work out what the next steps are. But those sorts of things that you can control in a situation — versus there’s a lot of things that are kind of outside of our control — are the ones that I would focus the most on.”

If you have any of the elements that place you at increased risk of developing more severe disease and you begin to show symptoms, Shenoy said you should contact your doctor.

“Reveal the symptoms you’re having, explain the symptoms and if you’ve had any of those exposures that we talked about, because that allows the person on the other end of the phone to figure out the best way to get you evaluated if you need to be evaluated,” Shenoy said. “Now, if your symptoms are quite mild, just like with the flu, many people can handle that by just staying home, limiting exposure to other people, and doing the common things that we do for upper respiratory tract infections that is kind of all the time each year when we get these infections. … The providers are going to have to sort out whether or not you need an in-person evaluation or close monitoring basically on the phone at home until you figure out what the next steps are.”

Everyone can limit their risk of exposure by practicing the behaviors typically employed to prevent the spread of the flu or colds each year, Shenoy said. 

“You can limit your exposure by trying to stay away from sick people, doing the hand hygiene and all that,” she said. “And if you develop illness, like you would have developed illness this time last year when we didn’t even know about this virus, you would hopefully do the same things. Like don’t go to work, keep your kids home from school if they have those symptoms, and limit the spread to other people.”

With the coronavirus, keeping an eye on alerts about travel is important, she said. 

“Be flexible about the concept that you may have to change your plans or that there may be disruptions in your everyday life around school or large gatherings that you just all have to adjust to and do the best that we can,” the doctor said. “And rely on the experts out there to help us work our way through it.”

You may have a healthy immune system, she said, but the person sitting next to you might not. 

“You have to do your part,” Shenoy said. “Be glad that you’re a healthy person generally and then do your part to make sure that others aren’t exposed unnecessarily.”

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Related video: What are the symptoms of coronavirus, and how is it treated?

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