Human Papillomavirus Prevalence in Asymptomatic Men

Abstract

Introduction: Human papillomavirus (HPV) is the sexually transmitted etiologic agent of cervical cancer. While HPV infects both men and women, little is known about HPV infection in men. Specifically, knowledge of the prevalence of type-specific HPV infection and the distribution of these infections by anogenital anatomic site in men is incomplete. Evaluation of factors associated with HPV infection based on complete anogenital sampling and with HPV-16 antibody detection may lead to a better understanding of HPV transmission and prevention.Methods: A total of 493 asymptomatic men ages 18 to 40 years old were recruited in Tucson, Arizona, and Tampa, Florida, from 2003 to 2006. Eligibility requirements included having had sex with a woman within the past year and having no history of genital warts. Testing for HPV from anogenital swabs from six anatomic sites and semen was conducted by PCR and reverse line blot genotyping for 37 HPV types. Serum antibodies for HPV-16 were detected by ELISA. Self-administered demographic, health, and sexual history/behavior questionnaires were collected. HPV prevalence and type distributions by anatomic site were calculated, as was seroprevalence of HPV-16 antibodies. Multivariate logistic regression was used to identify independent risk factors for HPV infection at any anatomic site and for having HPV-16 antibodies.Results: HPV was detected in at least one sample for 303 (65.4%) men, with 29.2% of men having an oncogenic infection and 36.3% having a non-oncogenic infection. Multiple HPV types were detected in 27.2% of men. Factors associated with infection were a greater lifetime number of female sexual partners, currently smoking 10 or more cigarettes per day, lack of condom use, and more sexual partners in the past three months. HPV-16 antibodies were detected in the serum of 63 (12.8%) men, and detection was associated with increasing age and concurrent detection of HPV DNA in perianal or anal canal samples.Discussion: The combination of more complete anogenital sampling and sensitive HPV detection for 37 HPV types resulted in a higher HPV prevalence in asymptomatic men than previously reported. Smoking and condom use were the most important modifiable risk factors for HPV in men. These results have implications for research of HPV transmission.