Koprowski was the target of accusations in the press related to the "OPV AIDS hypothesis", which posited that the AIDS pandemic originated from live polio vaccines such as Koprowski's. This allegation has long been refuted by evidence showing that the HIV-1 virus was introduced to humans long before his polio-vaccine trials were conducted in Africa.[1] The case was settled out of court with a formal apology from Rolling Stone magazine.[2]