News Snapshot:
Fewer than 4% of adults in Wuhan, China, tested positive for antibodies against COVID-19 , putting the possibility of countries developing "herd immunity" against the virus without a vaccine in doubt, according to an analysis published Friday by JAMA Network Open . The findings also suggest that those who experience mild disease or who have no outward symptoms of the virus may not develop long-lasting immunity to it naturally, the researchers said. Advertisement The term herd immunity refers to a scenario in which most of a population has become immune to a virus and these people effectively provide indirect protection...