The new study’s design and size benefited from Denmark’s free and abundant testing for the coronavirus. Nearly 70 percent of the country’s population was tested for the virus in 2020. The researchers looked at the results from 11,068 people who tested positive for the coronavirus during the first wave in Denmark between March and May 2020. During the second wave, from September to December, 72 of those people, or 0.65 percent, again tested positive, compared with 3.27 percent of people who became infected for the first time. Most people produce robust immune response to a natural infection, “but there’s a lot of variability,” he said.

Source: New York Times March 17, 2021 23:26 UTC