Adults in their 30s, 40s and 50s—and even younger—are coming down with severe cases of COVID-19, the respiratory illness caused by the new coronavirus sweeping the globe. This means people of all ages need to take social distancing recommendations seriously.

Among the first wave of COVID-19 cases reported in the United States—before the steep upsurge in mid-March—nearly 40% of people who required hospitalization were under age 55.

“This isn’t just a disease of the elderly,” Mike Ryan, MD, director of the World Health Organization’s Health Emergencies program, said at a March 18 briefing. “There is no question that younger, healthier people overall experience much less severe disease, but a significant number of otherwise healthy adults can develop a more severe form of the disease.”

While around 80% of people who contract the coronavirus will have mild or moderate illness and recover without special treatment, about 20% will develop severe respiratory disease that may include pneumonia or respiratory failure requiring mechanical ventilation.

According to early reports from China, where the current pandemic emerged in December, a large majority of severe disease and deaths occurred among older adults and those with underlying health conditions. One large analysis of nearly 45,0000 confirmed cases by the Chinese Center for Disease Control and Prevention found that people in their 20s accounted for less than 1% of all deaths, rising to 2% for those in their 30s, 4% for those in their 40s and 13% for those in their 50s. Only one teenager died, and there were no deaths among those under age 10.

Numbers like these led to a widespread sense of reassurance that while younger individuals might contract the coronavirus, they were unlikely to develop severe illness, require hospitalization or die from it. As the pandemic spread to the United States and Europe, many young adults appeared to feel invincible as they ignored social distancing recommendations.

In recent days, as the economic impact of halting travel and shutting down businesses has become clear, President Donald Trump and others have suggested that the economic consequences might be lessened by allowing younger individuals to return to work and resume their social lives.

But public health experts, including National Institutes of Allergy and Infectious Diseases director Anthony Fauci, MD, and former Food and Drug Administration commissioner Scott Gottlieb, MD, stress that this would be unwise.

It’s increasingly clear that young adults can in fact develop severe COVID-19. A growing number of personal accounts in the press and on social media by young patients and their health care providers suggest that this may be more common than previously believed.

For example, The New York Times recently ran a story by Fiona Lowenstein, a 26-year-old writer and yoga teacher who was hospitalized with COVID-19 despite being a nonsmoker and not having underlying health conditions. Similar to other reports from young patients, she had mild initial symptoms that appeared to improve, only to be followed by worsening shortness of breath.

“Millennials, if you can’t be good allies, at least stay home to protect yourselves,” she wrote. “Our invulnerability to this disease is a myth—one I have experienced firsthand.”

A recent analysis published in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report looked at severe outcomes among 4,226 individuals with COVID-19 reported through March 16. The study authors noted that the data are incomplete and do not include outcomes for all patients or information about underlying health conditions. Preexisting conditions such as heart disease, chronic lung disease, high blood pressure and diabetes are associated with a greater risk of severe disease and death.

As expected, older people bear the brunt of severe COVID-19 illness and death. Overall, 45% of hospitalizations, 53% of intensive care unit (ICU) admissions and 80% of deaths occurred among those age 65 or older. In contrast, no ICU admissions or deaths were reported among those under 19.

But younger adults were not spared. Among the people known to have been hospitalized, 18% were ages 45 to 54, and 20% were 20 to 44. Among the 121 people admitted to an ICU, 36% were 45 to 64, and 12% were 20 to 44. Accounting for missing data, the researchers estimated that 14% to 21% of young adults in the latter age range required hospitalization, and 2% to 4% needed intensive care.

Of the 44 reported deaths, nine (20%) involved people in the 20-to-64 age range. Although the researchers reported a fatality rate under 1% for people ages 20 to 54 and 1% to 3% for those ages 55 to 64, this adds up to a large number of young and middle-aged adults when considering the size of the U.S. population.

“These data show that severe illness leading to hospitalization and death can occur in adults of any age,” the study authors concluded. “Social distancing is recommended for all ages to slow the spread of the virus, protect the health care system and help protect vulnerable older adults.”

Click here to read the CDC study.

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