BACKGROUND: In the United States, HPV vaccination has been recommended since 2011 for males aged 11-12 years, with catch-up vaccination recommended through age 26 years for previously unvaccinated men who have sex with men (MSM). METHODS: During 2016-2018, a cross-sectional study enrolled MSM and transgender women aged 18-26 years in Seattle, Washington. Participants submitted self-collected penile swab specimens for HPV genotyping. HPV vaccination history was self-reported. We compared HPV prevalence among vaccinated participants versus participants with no/unknown vaccination history using log-binomial regression to estimate adjusted prevalence ratios (aPR) and confidence intervals (CI). RESULTS: Among 687 participants, 348 (50.7%) self-reported ever receiving ≥1 HPV vaccine dose; median age at first HPV vaccination was 21 years and median age at first sex was 17 years. Overall, prevalence of penile quadrivalent HPV vaccine (4vHPV)-type HPV was similar in vaccinated participants (12.1%) and participants with no/unknown vaccination (15.6%) (aPR=0.69, 95%CI:0.47-1.01). However, prevalence was significantly lower in participants vaccinated at age ≤18 years than in participants with no/unknown vaccination (aPR=0.15, 95%CI:0.04-0.62), corresponding to a vaccine effectiveness of 85% against 4vHPV-type HPV. CONCLUSIONS: Results suggest HPV vaccination is effective in preventing penile HPV infections in young MSM when administered at age ≤18 years.

Using data from travelers to 4 countries in the Middle East, we estimated 3,250 (95% CI 1,300-6,600) severe cases of Middle East respiratory syndrome occurred in this region during September 2012-January 2016. This number is 2.3-fold higher than the number of laboratory-confirmed cases recorded in these countries.