When the first cases of COVID-19 started being diagnosed in Wuhan, China, health experts believed that the highly infectious was most detrimental for older people or those with preexisting health conditions. However, as the virus has continued to spread around the world and more research has been conducted, it has become clear that younger, healthy people are not immune to serious health ramifications if infected with coronavirus. On Monday, Dr. Fauci issued a warning to all those younger Americans who falsely believe that they will bounce back from an infection unscathed, when in fact their health could be compromised for several months —and possibly longer.

"They Have Residual Symptoms for Weeks or Months"

"We'd better be careful when we say 'Young people who don't wind up in the hospital are fine, let them get infected, it's OK.' No, it's not OK," the nation's top infectious disease doctor warned during a briefing with the American Society for Microbiology.

He pointed out that many of the individuals who believe they suffered a "mild" case of the virus, meaning they don't even check into the hospital, take a significant amount of time to get back to normal.

"In individuals who are young and otherwise healthy, who don't require hospitalization but do get sick and symptomatic enough to be in bed for a week or two or three and then get better, they clear the virus—they have residual symptoms for weeks and sometimes months."

And, because the virus has only been around for months and not years, the damage could be permanent. Even months later, after several follow-up visits with medical experts, some of them "have a substantially high proportion of cardiovascular abnormalities, evidence of myocarditis by MRI and PET scans, evidence of emerging cardiomyopathies."

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It's "Really Troublesome"

Dr. Fauci describes this as "really troublesome" because experts don't really know the long-term ramifications. "These are people that supposedly recovered from Covid-19," he explained. "I'll guarantee you if we have this conversation again, six months to a year from now, we'll be reviewing the literature about talking about the long-term deleterious effects of non-hospitalized patients."

The medical world has come to identify these types of people who suffer lingering symptoms or damage as a result of the virus as "long haulers."

"We're starting to see more and more people who apparently recover from the actual viral part of it, and then weeks later, they feel weak, they feel tired, they feel sluggish, they feel short of breath," Fauci, a key member of the White House Coronavirus Task Force, explained during an Instagram interview last week with Matthew McConaughey.

"It's a chronic projection forward of symptoms, even though the virus is gone, and we think that's probably an immunological effect."

The CDC has also expressed concern about the longer-term damage that healthy Americans are sustaining after a COVID-19 infection. In late July they issued a report confirming that thirty-five percent of coronavirus sufferers surveyed who hadn't been admitted to a hospital, the majority who were under the age of 49, were still experiencing symptoms two to three weeks after testing positive for the virus.

"COVID-19 can result in prolonged illness even among persons with milder outpatient illness, including young adults," the report's authors wrote.

As for yourself, do everything you can to prevent getting—and spreading—COVID-19 in the first place: Mask, get tested if you think you have coronavirus, avoid crowds (and bars, and house parties), practice social distancing, only run essential errands, wash your hands regularly, disinfect frequently touched surfaces, and to get through this pandemic at your healthiest, don't miss these 37 Places You're Most Likely to Catch Coronavirus.