One is not none.

While over half of adolescents in the US have now received the Gardasil vaccine series, over two-thirds have received at least the first dose. Which stat is more important? This cross-sectional study of 1600 women with HPV testing and self-reported vaccine histories reported that infection with high-risk HPV subtypes was significantly less prevalent among those who had received one (HPV prevalence of 2%), two (5%) or all three (3%) Gardasil doses than among those who received no vaccine (13%). | Sonawane, JAMA Netw Open 2019