March 26, 2020 -- Even as spring breakers continued to party on Florida beaches, stories popped up across the internet over the last week about the new coronavirus infecting more and more young people, despite the conventional wisdom that seniors and the elderly were most at risk.
Stories about people like David Lat, 44, a lawyer and legal blogger, lying struggling to breathe at NYU Langone Medical Center. “I’ve never been this sick in my entire life,” he told Law.com, which says he was healthy enough to do intense interval training and walk about 25 miles a week before catching the virus.
And Twitter was rife with threads like: “One of my friends has COVID-19 and is in the ICU. He's in his late 20s and not in an at-risk population. I don't know what's going on.”
Little Data on Demographics
It’s not yet clear whether younger adults in the United States are more vulnerable to serious infections than those in other countries. But a study last week from the CDC found that 20% of hospitalized patients were ages 20 to 44.
“Early on, we had this feeling that it really wasn’t affecting young people at all,” says Natalie Dean, PhD, an assistant professor of biostatistics at the University of Florida in Gainesville. “But what we’re seeing, in Italy and in other places, [are] younger people being hospitalized, having to be admitted to the ICU.”
The data from China showed that older people were more likely to die. But Americans may have misunderstood the data that initially came out of China: that older people were most affected and younger ones were safe.
“Older people are at greater risk of getting sicker, but it’s not that young people are not at risk,” says Jennifer Kates, PhD, senior vice president at the Kaiser Family Foundation, an independent nonprofit that provides information on national health issues.
Public health officials have been warning at-risk older adults to protect themselves. Some younger adults took that to mean they were safe.
Kates, appalled, points to one group of 20-somethings who held a “coronavirus party” that led to at least one infection. A handful of people who were partying on Florida beaches last week have now tested positive.
COVID-19 seems to infect people in every age group equally -- it’s just that the risk of very serious disease and death rises with age, says Caroline Buckee, DPhil, an associate professor of epidemiology at the Harvard T.H. Chan School of Public Health. “Young people still can get severely ill.”
In China, people under 40 accounted for only 2.5% of deaths, according to a study of more than 70,000 patients with confirmed cases as of Feb. 11.
But just because younger adults aren’t dying from COVID-19 doesn’t mean they aren’t suffering.
The data out of China showed that some people had no symptoms at all and 80% of cases were “mild” -- meaning the person didn’t end up in the hospital. But what we’re seeing in the United States shows that many people fall between these two extremes, suffering from “the worst flu of my life,” or having day after day of aches, coughs, and malaise.
And some fare even worse.
Plenty of Younger People Getting Sick
Among the earliest patients diagnosed in the United States, 29% were ages 20 to 44, according to the CDC report -- which is roughly equal to the percentage of Americans in that age group. Younger adults accounted for more hospitalizations with COVID-19 than any other group, besides those ages 65 to 74.
Harvard University epidemiologist Marc Lipsitch, DPhil, questioned how reliable the CDC’s data is, because patients with severe symptoms are more likely to get tested and therefore included. “I would say it is premature to conclude much from those findings,” he says.
It’s still impossible to say exactly what percentage of younger adults gets severely ill, because researchers don’t yet know how many people in a population are infected, Buckee said on a conference call with media. Some people catch COVID-19 but never know it because they don’t have symptoms.
Researchers will need to do blood tests on a large population of people -- which hasn’t been done yet anywhere in the world, because the virus is so new -- to see whether people without symptoms account for a large number of infections, or just a few. If nearly everyone has mounted an immune response to the virus, then it’s only a relatively small population that got quite sick, Buckee explained.
It’s also too soon to know whether behavior has any effect on how serious someone’s infection will be. The only things known to increase the risk of a serious infection are overall health, age, and other illnesses someone might have, like heart disease or diabetes, Buckee says.
That hasn’t stopped people on Twitter from blaming younger adults for their illnesses. In a Twitter thread about the 25-year-old former lacrosse player, posters said he must have been vaping or had pre-existing conditions, though people who talked with his family said otherwise.
Medical personnel may be at particularly high risk for severe infections. Several young doctors treating patients in China died after becoming infected.
In the United States, as infections spread, reports of sick medical workers have begun to tick upward.
And, in the general population, one Twitter user summed up the situation in her mind. “This virus will come for all of us. It doesn't seem like a threat until it's *your* friends texting each other panicked. Take it seriously.”