At the beginning of the coronavirus outbreak in the US, most Covid-19 cases seemed to be in older folks, who were getting very sick — an artifact of who was getting tested at the time.
But now, especially in states where Covid-19 cases have been rising in June and July, the median age has been dropping.
“We are seeing it in a much younger group, of 20- to 40-year-olds,” compared to the earlier stage of the pandemic, says Thomas Tsai, a health policy expert and surgeon at the Harvard T.H. Chan School of Public Health.
In Florida, where the coronavirus has infected more than 311,000 residents, the median age of positive cases in March was 65. As of July 17, the median age of new cases from the previous 14 days was 39.5.
In Arizona, 61 percent of Covid-19 cases are in people under the age of 45. In Texas’s two largest counties, Harris (home to Houston) and Dallas, about half of the new cases have been in people under 40.
Other states with worrying rises in case numbers are seeing a similar trend. In California, which just reclosed bars and indoor dining, as of July 15, people ages 18 to 34 made up the largest proportion of new cases (24.3 percent), with 35- to-49-year-olds as the second-largest group (19.3 percent of new cases). Even Virginia, where cases have been relatively stable, has seen an increase in new cases among people in their 20s.
Nationwide, “the average age of people getting infected is now a decade and a half younger than it was a few months ago,” Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said in a July 6 press briefing.
Younger people, on average, are less likely to become severely ill and die of Covid-19 — although many do. They can also spread it to older people who are much more vulnerable to severe infection and death.
This seems to already be happening, with assisted living facility cases climbing in Houston and Phoenix, as well as in Florida now. “We first see it in the community, and then we see it in the residents and staff, and then you see the deaths,” David Grabowski, a health care policy expert at Harvard Medical School, told the Wall Street Journal.
Check out this helpful visualization of the ages of new cases in Florida. With many more cases in younger adults (orange band), we are closely tracking spillover into older adults (red and gray bands).— Natalie E. Dean, PhD (@nataliexdean) July 14, 2020
Credit: @jasonsalemi https://t.co/TYinXKTQa1 pic.twitter.com/UQgsBq5GS7
So even if you’re a young person who gets infected and don’t get very sick, “you’re part of the propagation of the pandemic,” as Fauci put it.
So how did the coronavirus suddenly start spreading to so many young people?
We’ve known that bars and other crowded indoor spaces are hubs of spread in the new hot spots. But there are likely many other factors at play.
THINK LIKE AN EPIDEMIOLOGIST:— Natalie E. Dean, PhD (@nataliexdean) June 23, 2020
What does it mean that the median age of new cases is dropping in some areas? I see three possible explanations, not all good. A thread on how to distinguish between them. 1/10
(Figure h/t @ScottGottliebMD) pic.twitter.com/Y6m45qoBL6
Some of these factors include mixed public health messaging and premature reopenings, young people skipping precautions because they perceive a lower risk of getting very sick, people returning to jobs, and more testing of people without symptoms. Let’s unpack some of these, which can help us better understand — and possibly slow — this new trend.
Who exactly counts as “young,” anyway? Due to imperfect and inconsistent data, it’s hard to say.
Getting a clear picture of the age demographics of new Covid-19 cases is not as simple as you’d think. States are on their own to decide whom they group together in their statistics, which can make the definition of “young” very different from place to place — and result in skewed numbers.
Arizona, for example, has lumped together people ages 20 to 44, which shows a huge number of cases. But this group is also the largest span of years the state measures, compared to other groups (such as the 55-to-64 age range, which spans just nine years). (These age groupings might be a legacy from the earlier days of the pandemic, when we were trying to better understand the illness’s severity in older adults.)
Arizona also displays cumulative cases since the beginning of the pandemic for each age group, whereas California highlights the number of new cases by age group for each week. This difference makes it harder to compare the age ranges involved in spreading the virus currently and historically.
To make things even more challenging, most states are also primarily reporting the overall number of cases per age group — rather than the percentage of that demographic’s population. (We can see from states that are providing this information that rates among different age groups can be very different than overall case counts might lead you to believe. For example, Massachusetts’s largest raw number of cases have been in people ages 50 to 59, but by percentage, the rate has been far greater in people over 69.)
Another way to get a sense of how prevalent the virus is in different age groups is to look at the rate of tests coming back positive. This is still not a perfect metric (and depends a lot on who — people who are symptomatic, high-risk individuals, those going back to work, etc. — is being tested). But it does help provide a sense of proportionality for a rough comparison of how frequently people in different age groups are likely to come back with a positive Covid-19 test.
And US Centers for Disease Control and Prevention data can differ from what states are reporting. For example, a recent Bloomberg report found that the CDC was likely underreporting the rate of Covid-19 infections in people under the age of 18 compared to what many states were showing.
Without more uniform — and, in some cases, more granular — data, it can be difficult to pin down precisely which age groups might be most prone to be spreading the virus in different places and what behaviors would be best to target to change. After all, a bunch of partying teens, for example, is a different public health problem to solve than middle-aged folks returning to office work.
Younger people do get sick and are now showing up in hospitals
On average, people younger than 65 tend to have a lower risk of getting extremely sick and dying from Covid-19. Because of this, by and large, “we may not see as high of hospitalization, ICU, fatality rates as we did in March and April with nursing home-driven clusters of infections,” Tsai says. And this had borne out so far, as Dylan Scott reported for Vox in early July.
A higher percentage of young people — and a lower percentage of elderly people — getting infected could seem like a good thing. For one, it should mean fewer deaths. It also should mean less strain on the health care system and its workers. But in the states with larger outbreaks, including Arizona and Texas, hospitals are already getting overwhelmed with young and old alike.
Hospitals in Florida are now requesting additional medical personnel to keep up, and those in Houston and Phoenix have exceeded their capacities. When that happens, “it’s horrifying,” says Jay Wolfson, a public health and policy expert at the University of South Florida. “It’s a slippery slope,” of hospitalizations rising and exceeding hospital capacity, “and it goes really, really fast.”
For the last week in June, more than 40 percent of Covid-19 hospitalized patients were 18 to 49 years old. That same age group made up just a quarter of hospitalizations in March and April.
Young smokers are particularly at risk, according to new research in the Journal of Adolescent Health. “Recent evidence indicates that smoking is associated with a higher likelihood of Covid-19 progression, including increased illness severity, ICU admission, or death,” said study author Sally Adams of the UCSF Division of Adolescent and Young Adult Medicine in a statement. “Smoking may have significant effects in young adults, who typically have low rates for most chronic diseases.”
Since the outbreak’s start in the US, the coronavirus has sent more than 9,000 people under the age of 50 to the hospital, and it has killed about 1,000 people in the US under the age of 35, as of July 17. (Possibly more due to likely underreporting, and there are likely more to come, given that deaths usually occur a couple of weeks after symptoms appear.)
Even if an infection doesn’t send someone to the hospital, it can “put them out of action for weeks at a time,” Fauci said in the July 6 press briefing.
There are also emerging long-term risks for young people who contract the virus — even if they don’t get severely ill at first. For example, among those who have ostensibly “recovered” from their initial Covid-19 infection, many describe persistent debilitating symptoms. And some of those health impacts might be long-term.
“Even if you have a mild or asymptomatic case, some percentage of everybody who gets it is going to acquire a new disease,” says Wolfson, who lists lung, vascular, and kidney diseases as some of the potential “persistent-acquired diseases” popping up from Covid-19 infections.
“You could be a perfectly healthy 21-year-old,” he says, and after a couple of weeks of recuperating from the virus at home, you’re getting back up but still have some shortness of breath, “and four months later find out that you got scarring in your lungs. And that’s not going away.” He calls it “the virus that keeps on giving.” And not in a good way.
Why milder infections among younger people might be making outbreaks worse for everyone
Although the new case increases in younger people have been treated by some government officials, such as Florida Gov. Ron DeSantis, as good news, there is another side to this story. If younger people are less likely to get severely ill, they may be more likely to shrug off recommendations about masking up and maintaining physical distancing, further spreading the virus to those in higher-risk groups.
As Wolfson explains, coronavirus transmission doesn’t change based on your age or risk of dying. “The calculus to this disease is proximity, congestion, and time,” he says. So “the closer you are to large groups of people for a longer period of time, it is exceptionally likely that somebody in that crowd is going to be a carrier.”
Another challenge is that a lot of the pandemic’s impacts might seem removed for some young adults who feel perfectly healthy. Covid-19 might sound like something for their grandparents or other older family members to worry about. And the societal questions, such as the urgency of reducing transmission so that schools can fully reopen in the fall, might not feel that personally relevant to young people eager to hang out with friends if they’re out of school and don’t have school-age children of their own.
The social isolation of shutdowns also seems to be taking a much higher psychological toll on younger than older adults, and is potentially driving them to gather in risky indoor settings. A CDC study in May found that nearly half of all 18- to 29-year-olds surveyed had been feeling at least some symptoms of anxiety or depression — a higher proportion than for other age groups (which was closer to one-third for those 30 to 59). (The CDC now also offers specific guidance for teens and young adults who might be struggling.)
Why young people don’t deserve all the blame
Plenty of young people are taking the pandemic very seriously and practicing the recommended precautions. “I’m trying to be a team player,” Lily Scott, 18, of Austin, told Bloomberg. “There are so many of us being cautious and trying to flatten the curve,” she said. “It’s hard to see our generation being represented this way.”
And other reports are trickling in that many younger Covid-19 patients have gotten sick not from bar-hopping or parties but just from going to work. In Florida, for example, the Miami area’s network of public hospitals says it has “been seeing waves of younger, working-age patients who have no choice but to work and, in turn, expose themselves to the virus,” the Miami Herald reported earlier this month.
Some experts also speculate that the uptick in cases among younger Americans could be partially due to a shift in who’s getting tested, because tests are more accessible than they were in March and April. During those early months, tests were largely reserved for those who had serious signs of illness and the highest-risk individuals, a large number of whom were much older.
“With additional testing available, more people in lower-risk populations are likely being tested,” according to the Covid Tracking Project, which includes younger, healthier people. Additionally, they note, “workplace testing may also increase case numbers for the working-age population, and perhaps particularly younger-skewing service workers.”
Catherine Troisi, an infectious disease expert for University of Texas School of Public Health, even thinks that “young people are being made maybe a scapegoat” for these new surges of Covid-19. Instead, she says, “everybody bears a little bit of responsibility.”
She places some on officials who have been sending mixed messages. For example, although Texas Gov. Greg Abbott instituted a mask order in early July, he had previously disallowed local governments from instituting such requirements.
Around the same time, Florida Gov. DeSantis said at a press conference that “there’s no need to really be fearful” about the situation. Although he advised people older than 65 or with high-risk health conditions to take general precautions, he did not extend this to younger, healthy folks, which contradicts recommendations from national experts.
“Certainly having better risk communication messages would be the first place I would start,” Troisi says.
Additionally, many states now seeing surges in the virus, including Texas, rushed to reopen perhaps earlier — and more quickly — than they should have, she says. After the state began closing businesses in the spring, experts there had agreed on key metrics that would need to be met before they started reopening. Instead, “that was thrown out the window,” Troisi says. And, “we didn’t wait long enough to see what happened once we opened up a little bit. We wound up opening more without seeing what the effects of the first opening were,” she says.
And those effects have been brutal, which Abbott has acknowledged. “If I could go back and redo anything, it probably would have been to slow down the opening of bars, now seeing in the aftermath of how quickly the coronavirus spread in the bar setting,” the governor said in a June radio interview.
Other states and localities, such as Madison, Wisconsin, are reimposing previous restrictions like closing bars.
THREAD: Today a new order goes into effect further restricting, among other things, mass gatherings and restaurant and bar activity. We base these restrictions on public health data and evidence. Our data are not showing a large impact from protests at this time.— @publichealthmdc (@PublicHealthMDC) July 2, 2020
More onus could also be shifted to businesses to reinforce safe behaviors, says Tsai. As he notes, in Florida, for example, the state can now take away a bar or restaurant’s liquor license if the establishment isn’t enforcing distancing and other public health guidelines. And in Texas, among other states, restaurants can be fined if they don’t enforce the state’s new mask-wearing policy.
Testing has also been a challenge to stemming these spiraling case numbers, with many people waiting more than a week for results — a time during which they could continue spreading the virus, and when contact tracers lose valuable time finding others who might have gotten infected. Additionally, if someone who later tests positive for Covid-19 has been to a crowded bar or event — or many — it can be next to impossible to determine everyone they might have had contact with. (Mobile phone data, as used in other countries, may be much more helpful in making these connections than the self-reported information officials have relied on in the US.)
Even without perfect testing and tracing, though, there are ways to manage this situation better, where people can still get out a bit and see friends and even frequent some businesses, but in a safer way. Because, as Troisi says, “it’s not public health or the economy, it’s both. So we need good public health in order to shore up the economy.”
“I am so tired of being home,” she says. “But you can’t wish the virus away. The only way we have to control it and to stop deaths right now is through these mitigation efforts.”
In short, everyone, young and old, will need to have some level of “personal discipline and a recognition that this is real,” Wolfson says. Because “the government is not going to save us from this.”
Katherine Harmon Courage is a freelance science journalist and author of Cultured and Octopus! Find her on Twitter at @KHCourage.