HPV vaccine efficacy in preventing persistent cervical HPV infection: A systematic review and meta-analysis

IntroductionWe performed a pooled analysis of randomised clinical trials (RCT) on HPV vaccine efficacy in preventing cervical persistent infection.MethodsWe carried out a bibliographic search on electronic databases and we selected RCT to perform the meta-analyses.ResultsWe selected five studies. The first meta-analysis, including all studies, showed an important reduction of the risk of infection from HPV 16 in vaccinated cohort [RR 0.10 (95% CI: 0.07–0.15)]. The second and third meta-analyses, including only studies on bivalent and tetravalent vaccines, showed a RR of 0.13 (95% CI: 0.09–0.20) for HPV 16 infections and a RR of 0.22 (95% CI: 0.13–0.38) for HPV 18 ones.DiscussionHPV vaccine efficacy in preventing persistent infection is high but there is the need for further studies on the duration of immunization and long-term vaccine efficacy.