But as the virus continued its rampage over the summer and fall, infecting nearly 8.5 million Americans, survival rates, even of seriously ill patients, appeared to be improving. At one New York hospital system where 30 percent of coronavirus patients died in March, the death rate had dropped to 3 percent by the end of June.

Doctors in England observed a similar trend. “In late March, four in 10 people in intensive care were dying. By the end of June, survival was over 80 percent,” said John M. Dennis, a University of Exeter Medical School researcher who is first author of a paper about improved survival rates in Britain, accepted for publication in the journal Critical Care Medicine. “It was really quite dramatic.”…

“This is still a high death rate, much higher than we see for flu or other respiratory diseases,” said Dr. Leora Horwitz, director of NYU Langone’s Center for Healthcare Innovation & Delivery Science and senior author of the paper in Journal of Hospital Medicine. “I don’t want to pretend this is benign. But it definitely is something that has given me hope.”