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The efforts of the healthcare community to promote female human papillomavirus (HPV) vaccination and reduce the incidence of cervical cancer have overshadowed the importance of male HPV immunization. A need for greater emphasis on promoting male vaccination for HPV was magnified through the recent results of the 2013-2014 National Health and Nutrition Examination Survey (NHANES), which brought to light the importance of protecting males against HPV.1 In a subset of 1,868 men, the overall genital HPV infection prevalence was 45.2%, and the high-risk oncogenic HPV prevalence was 29.5%.1 Per NHANES, the oral HPV infection rate among males is 11.5%, which translates to 11 million men and is three times the prevalence rate of female oral HPV infection.2 The Centers for Disease Control (CDC) estimates that 74% of the 19.7 million new sexually transmitted infections in the United States each year are HPV infections.3
HPV and associated cancers
Eight HPV genotypes—HPV 16, 18, 31, 33, 35, 45, 52, and 58—have been identified as oncogenic; that is, these genotypes have an increased risk of mutating into cancer.4 HPV 16 and 18 are the genotypes most commonly associated with the development of anal, oropharyngeal, penile, cervical, vaginal, and vulvar cancers.5 Although all cases of HPV exposure and infection do not result in cancer development, the HPV vaccine series provides hope for significant long-term reduction of HPV-related cancer incidence among males and females.
For optimal vaccine effectiveness, HPV immunization should be offered to all adolescents at age 11 or 12 years or before the onset of sexual intimacy.6 The most recent estimates show that 42% of adolescent boys have received one or more doses of the HPV vaccine, an increase of 8% from the 2013 National Immunization Survey–Teen estimates for boys.7 These statistics reflect a very gradual increase in HPV vaccine uptake. However, it is notable that with currently fewer than 50% of males being vaccinated, a segment of the male population annually ages out of the recommended age vaccine cohort but remains at risk for exposure and uptake of all HPV genotypes.
Current data suggest that HPV infection rates in young males may range from 45% to 93% when both low- and high-risk populations are considered.8 The importance of recommending male vaccination cannot be overemphasized, because the risk of male-to-female HPV transmission is significant. A recent meta-analysis examining HPV concordance among heterosexual couples indicated that HPV is more readily transmissible from infected males to females than the reverse.9