High Risk of Incident-Persistent Human Papillomavirus Infection With 9-Valent Vaccine Types in Young Men With an HPV Infection.

Background: Studies evaluating the association between prevalent human papillomavirus (HPV) infection and the risk of future incident-persistent infection in a broad global sample of men are needed. Methods: Heterosexual men (HM) and men who have sex with men (MSM) aged 16-27 years in the placebo arm of a multinational 4-valent HPV vaccine trial (NCT00090285) were assessed. Incident-persistent infection was defined as a new 9-valent (9v) HPV (HPV6/11/16/18/31/33/45/52/58) type at follow-up that was not present at the same anatomic site at baseline and that remained detectable at that same site for 2 or more consecutive visits approximately 6 months apart. Association between baseline prevalent 9vHPV infection and incident-persistent infection at anogenital sites was estimated using incidence rate differences (IRDs) and incidence rate ratios (IRRs). Results: Included were 1459 HM and 260 MSM. Incidence rates (per 100 person-years) of incident-persistent infection among HM with or without baseline prevalent 9vHPV infection were 10.18 and 5.94, respectively, and among MSM were 11.74 and 9.78, respectively. Baseline prevalent 9vHPV infection status was associated with incident-persistent 9vHPV infection among HM (IRD, 4.24 [95% CI, 1.24-7.23]; adjusted IRR, 1.52 [1.11-2.09]) but not MSM (IRD, 1.96 [-4.01 to 7.93]; adjusted IRR, 1.02 [0.59-1.79]). Conclusions: HM with baseline prevalent 9vHPV infection were more likely to develop an incident-persistent anogenital infection than those without baseline prevalent infection. Risk of incident-persistent infection among MSM was high regardless of baseline prevalent 9vHPV infection status. These findings highlight the importance of vaccinating men against HPV infection.