The U.S. is seeing a "disturbing surge" of COVID-19 infections, particularly in the Southeast and West, Dr. Anthony Fauci said during a House Energy and Commerce Committee hearing Tuesday.
Playing a large part in this surge, health officials say, are increasing cases in younger people, in their 20s, 30s and 40s — increases that are driven, in part, by increased testing, but even more so by large gatherings.
Fauci, director of the National Institute of Allergy and Infectious Diseases, acknowledged that young people have a "pent up urge" to go out into public spaces, but stressed the need to continue physical distancing and wear face coverings to prevent spread of the virus.
"The next couple of weeks are going to be critical in our ability to address those surges that we're seeing in Florida, Texas and Arizona," Fauci said.
The coronavirus spreads mainly from person to person through respiratory droplets from coughing, sneezing, talking and singing.
"I've seen bars and restaurants that look like it's New Year's Eve 1999 — not a care in the world, nobody wearing masks, standing shoulder to shoulder," said Dr. James McDeavitt, senior vice president and dean of clinical affairs at Baylor College of Medicine in Houston.
The number of COVID-19 cases has begun to rise as college athletes resume training. Members of the University of Houston football team have tested positive, as have players at the University of Texas at Austin and Clemson University in South Carolina.
McDeavitt said Houston is seeing "very rapid increases" in new patients sick enough to be hospitalized, although the age range of the patients is unclear. However, most of those patients don't need intensive care or mechanical ventilation, McDeavitt said.
That suggests that current patients aren't quite as sick as those who fell ill in March and April. McDeavitt said that while it's true that doctors now have access to treatments like remdesivir and convalescent plasma, "our leading hypothesis is that we are probably seeing a slightly younger patient population."
In general, older adults and those with chronic health problems have been more likely to develop more serious complications of COVID-19.
During a conference call Monday, Vice President Mike Pence told governors that a growing number of people under age 35 are testing positive for COVID-19, especially in hard-hit states such as Florida and Texas.
According to sources who were on the call, Pence said the White House is working with those states to address the rise in cases.
Texas Gov. Greg Abbott said at a news conference last week that certain counties have reported that people under age 30 represent a majority of positive COVID-19 tests. On Monday, he said the spread of the coronavirus is "unacceptable."
It's a similar situation in Florida. During a news conference last week, Gov. Ron DeSantis said the average age of COVID-19 patients in the state had declined dramatically in recent months — from the 60s to 37.
"Those under 40, in particular, who don't have any significant underlying conditions, are much, much less likely to be hospitalized or to suffer fatality," DeSantis said. However, over the weekend, the state Health Department confirmed Florida's first COVID-19 death in a minor, a 17-year-old boy in Pasco County.
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"We are starting to see younger patients coming in, more 30-, 40-year-old patients coming in, late 20s," June Ellis, an associate chief nursing officer at Jackson Memorial Hospital in Miami, told NBC Miami.
Physicians in North Carolina, too, are seeing an uptick in COVID-19 among younger adults, even teenagers.
"As we're reopening, sports teams are getting back together and people are going to camps," said Dr. Katie Passaretti, medical director for infection prevention at Atrium Health in Charlotte. "We're starting to see some evidence of increased patients associated with that."
She echoed McDeavitt's observation that those patients don't seem to be as sick as older adults.
"We're not necessarily seeing an increase in the severity of disease. It's just that we're seeing evidence of more transmission," Passaretti said.
"Some people would like to say, well that's not a big deal because young people don't get as sick," Dr. Ashish Jha, director of the Harvard Global Health Institute, said Tuesday on "TODAY." "But young people are then going to spend time with their parents and grandparents."
"Just because it starts with young people, doesn't mean it will stay with young people," Jha said.
Judith Malmgren, an affiliate assistant professor at the University of Washington's epidemiology department, noted a marked shift to younger COVID-19 cases in Washington in March and April in a study she co-authored. The study was posted to a preprint server and hasn't been published in a peer-reviewed journal.
Malmgren said she, too, has noticed large numbers of young adults gathering in large crowds. But beyond that, people involved in essential work are more likely to be 20- to 39-year-olds, she said.
"They're also more likely to have interaction with the public, for example, packing your groceries at the grocery store," Malmgren said. "It's just the way that COVID-19 is spread, human to human, face to face."
Experts say there are ways to minimize risk as people try to get back to some level of normal life without pushing the economy back into a lockdown. They include wearing face coverings, remaining vigilant about hand hygiene, staying about 6 feet away from others in public and avoiding others if you become sick.
"Everybody needs to take personal responsibility," McDeavitt said. "If we do those things, that will replicate a lot of what a lockdown does.
"But the challenge I see," McDeavitt added, is that "some people are taking it to heart, and others are acting like they're not in the middle of the worst global pandemic of this century."