Dr. Anthony Fauci, the US's top infectious-disease expert, has consistently worked to warn young Americans about the health risks of the new coronavirus.

Typically, people older than 65, or people with underlying health conditions, are disproportionately at risk of contracting the COVID-19 virus.

These statistics have deterred some younger Americans from complying with Centers for Disease Control and Prevention (CDC) recommendations to eliminate gatherings of more than 50 people.

But according to Fauci, "young people need to take this very seriously" — both to ensure that they "don't inadvertently pass on the infection to someone who would not fare as well," and because they themselves could be at risk.

New research from the CDC shows that, as of last week, 30% of Americans infected with the new coronavirus were between ages 20 and 44.

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The US' top infectious disease expert, Anthony Fauci, is pleading with all Americans but especially younger generations: stay home to protect others from the new coronavirus, but also yourself.

"You are not immune or safe from getting seriously ill," Fauci, director of the National Institutes of Health's infectious diseases division, told CNN on March 15 after being asked if young people were at risk of contracting the virus.

States across the country, like New York and California, have imposed mandatory shelter-in-place and stay-at-home orders to facilitate social distancing and slow the spread of the virus. But according to Fauci, young Americans are not taking these prevention measures as seriously as they need to.

Last week, Ohioan Brady Sluder became the poster boy for Fauci's concern by refusing to take the coronavirus pandemic seriously.

"If I get corona, I get corona," Sluder told Reuters amidst a throng of people partying on Miami Beach in a video shared by CBS News on Wednesday. "At the end of the day, I'm not going to let it stop me from partying."

Hordes of spring breakers at Florida beaches and Texas' South Padre Island last week certainly weren't following the CDC recommendations to eliminate gatherings of more than 50 people, or President Donald Trump's suggestion to limit such gatherings to 10 people.

Cece Guida, 19, top, of New York City, pushes on Sam Reddick, 20, of Evansville, Indiana, as spring break revelers look on during a game of chicken fight on Pompano Beach, Florida on March 17, 2020. Julio Cortez/AP

In a livestreamed Facebook interview with the company's CEO Mark Zuckerberg on Thursday, Fauci spoke broadly to young people like Sluder: "Please understand that you will play a major role in ultimately containing this infection by not being careless and avoiding and not listening to the recommendations of physical separation."

'You have a societal responsibility'

There are currently more than 46,000 US cases of the COVID-19 virus; the US now has the third-highest number of cases of any country. A week ago, the US' case count was about 4,000.

The virus has spread quickly in epicenters like New York City; Gov. Andrew Cuomo announced that New York State had more than 16,00o cases as of Monday morning — about 6% of all coronavirus cases worldwide, though that share continues to grow with a dramatic boost in testing.

Fauci told Zuckerberg that young people need to understand that they may be carriers for this disease, and spread it to more vulnerable subsets of the US population without ever feeling sick or showing symptoms.

"The fact is, that even though young people ... with some exceptions, as a group will not get seriously ill from this," he said, adding: "They will and can get infected. And even though there may be minimal symptoms or no symptoms at all, they become the vector to infecting those people who are vulnerable, who can get in trouble."

Every time Fauci speaks to a national media outlet about the role of young people during this outbreak, his talking points are the same.

Dr. Anthony Fauci, center, speaks at a White House press conference on the coronavirus outbreak on February 29, flanked by President Donald Trump, right, and Vice President Mike Pence, left. Andrew Harnik/AP

"There are two reasons why young people need to take this very seriously," Fauci told CNN on March 19.

"You have a responsibility, a societal responsibility, to protect the vulnerable, and you do that — interestingly — by not letting yourself get infected," he said, adding: "you need to make sure you don't inadvertently pass on the infection to someone who would not fare as well as you fare because you are young and healthy."

40% of people hospitalized with coronavirus in the US are younger than 54

The second reason why young people need to be more vigilant, Fauci said, is that they're still at risk.

"You, yourself could be in harm's way. I mean, obviously most of difficulties are in people who are older and/or have underlying conditions. And many young people who've actually gotten into trouble did have underlying conditions," he said, adding: "But you're not out of danger."

Typically, the coronavirus disproportionately infects people older than 65, or patients with health problems like heart disease or diabetes. But recent research from the CDC revealed that nearly one-third of US coronavirus cases were people between the ages of 20 and 44.

The CDC said it had confirmed 4,226 cases of COVID-19 in the US as of March 16; of the 2,449 cases in which it knew the patients' ages, 29% were between the ages of 20 and 44. The report also found that the same age group accounted for 20% of those hospitalized with the disease, as well as 12% of those admitted to intensive care, showing that younger people can develop severe cases, too.

A security guard leaves NorthBay VacaValley Hospital, where a woman diagnosed with coronavirus previously sought treatment, on Thursday, February 27, 2020. Noah Berger/AP

According to data provided by New York City Hall officials on Friday, more than 25% of the 1,160 coronavirus patients requiring hospitalization in New York City have been under the age of 50. As of Monday, NYC has reported more than 12,300 cases.

These findings further underscore Fauci's warnings.