Estimating HPV DNA deposition between sexual partners using HPV concordance, y chromosome DNA detection, and self-reported sexual behaviors

Abstract

Background. Detection of human papillomavirus (HPV) DNA in genital samples may not always represent true infections but may be depositions from infected sexual partners. We examined whether sexual risk factors and a biomarker (Y chromosome DNA) were associated with genital HPV partner concordance and estimated the fraction of HPV detections potentially attributable to partner deposition. Methods. The HITCH study enrolled young women attending a university or college in Montreal, Canada, and their male partners, from 2005 to 2010. We tested baseline genital samples for Y chromosome DNA and HPV DNA using polymerase chain reaction. Results. Type-specific HPV concordance was 42.4% in partnerships where at least one partner was HPV DNA positive. Y chromosome DNA predicted type-specific HPV concordance in univariate analyses, but in multivariable models the independent predictors of concordance were days since last vaginal sex (26.5% higher concordance 0-1 vs 8-14 days after last vaginal sex) and condom use (22.6% higher concordance in never vs always users). We estimated that 14.1% (95% confidence interval [CI], 6.3-21.9%) of HPV DNA detections in genital samples were attributable to vaginal sex in the past week. Conclusions. A substantial proportion of HPV DNA detections may be depositions due to recent unprotected vaginal sex.