Washington – Natural immunity was six times stronger during the delta wave than vaccination, according to a new report from the U.S. Centers for Disease Control and Prevention.
The report published Jan. 19 analyzed COVID outcome data from New York and California, which make up about one in six of the nation’s total COVID deaths.
After delta became the main strain, vaccines alone grew weaker against the virus and natural immunity got much stronger. This could be due in large part to the fact that vaccines began wearing off around the time delta spread, according to the study.
“Importantly, infection-derived protection was greater after the highly transmissible Delta variant became predominant,” reads the report, “coinciding with early declining of vaccine-induced immunity in many persons.”