New research suggests that COVID-19 is far from benign when it strikes young adults: Once they are hospitalized, 1 in 5 wind up in the ICU and many need ongoing medical care even after they are free of the virus, scientists report. The Harvard University doctors reviewed more than 3,200 coronavirus cases where adults aged 18 to 34 needed hospitalization. Twenty-one percent ending up requiring ICU admission and 10 percent needed a ventilator to breathe. Overall, 2.7 percent of young hospitalized patients died. Another 3 percent required care in a post-acute treatment facility even after clearing the virus from their bodies.