High Risk of New HPV Infection Acquisition Among Unvaccinated Young Men.

BACKGROUND: International data on anogenital HPV infection incidence among men are limited. METHODS: Incidence of incident-persistent (IP) anogenital HPV infections was evaluated among 295 men who have sex with men (MSM) and 1576 heterosexual men (HM) aged 16-27 years in the placebo arm of a global, multicenter 4-valent (4v) HPV vaccine trial. We estimated IP incidence (penile/scrotal, perineal/perianal, anal) for 4vHPV and 9-valent (9v) HPV vaccine types and cumulative IP incidence over 36 months. RESULTS: IP infection incidence per 100 person-years (95% CI) among HM for 4vHPV and 9vHPV types was 4.1 (3.5-4.9) and 6.8 (5.9-7.6) at penile/scrotal, and 1.2 (.8-1.6) and 1.9 (1.5-2.4) at perineal/perianal sites, respectively; and among MSM, IP infection incidence was 2.3 (1.3-3.8) and 3.2 (2.0-4.9) at penile/scrotal, 6.8 (4.9-9.2) and 9.0 (6.9-11.6) at perineal/perianal, and 12.0 (9.4-15.1) and 16.8 (13.7-20.2) at anal sites, respectively. Cumulative IP incidence over 36 months (excluding anal canal; any 9vHPV type) was higher among MSM versus HM (24.1% vs 18.4%). CONCLUSIONS: A substantial proportion of unvaccinated men of catch-up vaccination age developed IP 9vHPV-related infections. Gender-neutral vaccination could decrease male HPV infection, contribute to herd protection, and reduce disease burden. Clinical Trials Registration. NCT00090285.

Anogenital Human Papillomavirus (HPV) Infection, Seroprevalence, and Risk Factors for HPV Seropositivity Among Sexually Active Men Enrolled in a Global HPV Vaccine Trial.

BACKGROUND: In men, the incidence of human papillomavirus (HPV)-related cancer is rising, but data regarding male HPV infection and seroprevalence are available from only a few countries. METHODS: This analysis of a global HPV vaccine trial evaluated baseline data from 1399 human immunodeficiency virus-negative heterosexual men (HM) and men who have sex with men (MSM). Key objectives included assessment of HPV prevalence and risk factors for seropositivity to 9-valent HPV (9vHPV) vaccine types (6, 11, 16, 18, 31, 33, 45, 52, and 58), and concordance between seropositivity and prevalent HPV type. RESULTS: Overall, 455 of 3463 HM (13.1%) and 228 of 602 MSM (37.9%) were HPV DNA positive for any 9vHPV vaccine type at baseline. Infection prevalence and seroprevalence (≥1 9vHPV vaccine type) were 13.2% and 8.1%, respectively, among 333 HM from Europe, and 37.9% and 29.9%, respectively, among 335 MSM from Europe or North America. Among men with baseline infection, MSM had higher seroprevalence for concordant HPV types (39.5% vs 10.8% in HM). The seropositivity risk (irrespective of baseline infection status) was higher among MSM versus HM (age-adjusted odds ratio, 3.0 [95% confidence interval, 2.4-6.4]). Among MSM, statistically significant seropositivity risk factors included younger age at sexual debut, higher number of receptive anal sex partners, and less frequent condom use. No factors assessed were associated with seropositivity in HM. CONCLUSIONS: Higher proportions of MSM than HM were HPV DNA positive and seropositive, and concordance between HPV DNA positivity and seropositivity, a potential marker of true infection versus carriage, was higher in MSM. Most MSM and HM were seronegative for all 9vHPV vaccine types, suggesting the potential benefit of catch-up vaccination after sexual debut.Clinical Trials Registration. NCT00090285.