Source: The LancetPublished: September 7, 2013By: Aimée R Kreimer PhD, Christine M Pierce Campbell PhD, Hui-Yi Lin PhD, William Fulp MS, Mary R Papenfuss MS, Martha Abrahamsen MPH, Prof Allan Hildesheim PhD, Prof Luisa L Villa PhD, Jorge J Salmerón MD, Prof Eduardo Lazcano-Ponce PhD, Prof Anna R Giuliano PhD   Summary Background Oral human papillomavirus (HPV) infection causes a subset of oropharyngeal cancers. These cancers disproportionately affect men, are increasing in incidence, and have no proven prevention methods. We aimed to establish the natural history of oral HPV infection in men. Methods To estimate incidence and clearance of HPV infections, men residing in Brazil, Mexico, and the USA who were HIV negative and reported no history of anogenital cancer were recruited into the HPV Infection in Men (HIM) cohort study. A subset of the cohort who provided two or more oral rinse-and-gargle samples with valid HPV results and who completed a minimum of 2 weeks of follow-up were included in this analysis. Oral rinse-and-gargle samples and questionnaire data were obtained every 6 months for up to 4 years. Samples were analysed for the presence of oncogenic and non-oncogenic HPV infections by the linear array method. Findings 1626 men aged 18—73 years and with a median follow-up of 12·7 months (IQR 12·1—14·7) were included in the analysis. During the first 12 months of follow-up, 4·4% (95% CI 3·5—5·6; n=115 incident infections) of men acquired an incident oral HPV infection, 1·7% (1·2—2·5; n=53 incident infections) an oral oncogenic HPV infection, and 0·6% (0·3—1·1; [...]