Fewer than 1 in 10 Americans showed signs of past infection with the novel coronavirus as of late July, suggesting that most of the country may still be vulnerable to infection, according to one of the largest studies of its kind published Friday in the journal The Lancet.
That proportion is an estimate based on the percentage of dialysis patients whose immune systems produced coronavirus antibodies. It does not indicate exactly how many Americans may be immune to the virus, because not every infected individual develops antibodies. It is also unclear how strong a defense antibodies might confer or for how long. But, combined with similar results from studies by the Centers for Disease Control and Prevention and other institutions, it’s evident a large majority may not be protected against a disease that has already killed 200,000 Americans.
“We are still in the middle of the fight,” said Eli Rosenberg, a State University of New York at Albany epidemiologist who was not part of the study. “We’re all tired, and we’re all hoping for a vaccine. This shows us how it’s not over here, not even by a long shot.”