Acquisition and persistence of human papillomavirus 16 (HPV-16) and HPV-18 among men with high-HPV viral load infections in a circumcision trial in Kisumu, Kenya

Background: Circumcision and lower human papillomavirus (HPV) viral loads in men are possibly associated with a reduced risk of HPV transmission to women. However, the association between male circumcision and HPV viral load remains unclear. Methods: Swab specimens from the glans and shaft of the penis were collected from men enrolled in a circumcision trial in Kisumu, Kenya. GP5+/6+ polymerase chain reaction (PCR) was used to identify HPV DNA types. HPV-16 and HPV-18 loads were measured with a LightCycler real-time PCR and classified as high (>250 copies/scrape) or low (≤250 copies/scrape). Results: A total of 1159 men were randomly assigned to undergo immediate circumcision, and 1140 men were randomly assigned to the control arm (these individuals were asked to remain uncircumcised until the study ended). The hazard of acquisition of high-viral load infections in the glans was lower in the circumcision arm, compared with the control arm, for HPV-16 (hazard ratio [HR], 0.32 [95% confidence interval {CI},.20-.49]) and HPV-18 (HR, 0.34 [95% CI,.21-.54]). The 6-month risk of HPV persistence among men with high-viral load infections in the glans at baseline was lower in the circumcision arm, compared with the control arm, for HPV-16 (risk ratio [RR], 0.36 [95% CI,.18-.72]) and HPV-18 (RR 0.34 [95% CI,.13-.86]). Weaker and less precise results were obtained for shaft samples. Conclusions: Male circumcision could potentially reduce the risk of HPV transmission to women by reducing the hazard of acquisition, and the risk of persistence of high-HPV viral load infections in the glans in men.