Nancy Messonnier, director of the Centers for Disease Control and Prevention’s (CDC) National Center for Immunization and Respiratory Diseases, told reporters on a conference call on Tuesday that health experts “do not expect most people to develop serious illness.”

In her opening remarks, Messonnier explained that there are two different risk pools for contracting coronavirus.

“Risk can be looked at in two ways,” Messonnier said.“There is risk of being exposed and getting sick from this virus, and there is risk of getting very sick or dying from illness with this virus.”

She explained that because no one can have immunity against a new virus, coronavirus will makes it way through the population.

“Based on this, it’s fair to say that as the trajectory of the outbreak continues, many people in the United States will at some point in time either this year or next be exposed to this virus, and there’s a good chance many will become sick,” Messonnier said.

She also explained who is most at risk for developing a potentially deadly case of coronavirus.

“Reports out of China that looked at more than 70,000 COVID-19 patients found that about 80 percent of illness had — was mild and people recovered,” Messonnier said. “Fifteen to 20 percent developed serious illness.”

“Let’s talk about who those people are,” Messonnier said. “So far it seems like it’s not children.”

“Of the 70,000 cases, only about two percent were in people younger than 19,” Messonnier said. “This seems to be a disease that affects adults. And most seriously older adults.”

“Starting at age 60, there is an increasing risk of disease and the risk increases with age,” Messonnier said. “The highest risk of serious illness and death is in people older than 80 years.”

She said people with serious underlying health conditions like diabetes, heart disease, or lung disease “are more likely to develop serious outcomes including death.”

Messonnier called on reporters to tell the public that people should have a plan for their families, including making sure medical prescriptions are filled and basic supplies are on hand.

That said, Messonnier also called on calm and common sense.

“This is a time for people to prepare for what they might need to do but not a time for people to clear out the shelves,” Messonnier said. “And I really want to focus on the United States and the families at highest risk because in the setting where it’s really clear that it is older Americans who are at the highest risk right now, we want to make sure that they’re taking every precaution to prepare themselves so that if there is more widespread transmission, they can stick close to home.”

She also said that masks are not recommended and should be reserved for healthcare workers who will need them when dealing with patients who have coronavirus.

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