Human Papillomavirus Viral Load and Transmission in Young, Recently Formed Heterosexual Couples.

BACKGROUND: We studied the association between human papillomavirus (HPV) viral load (VL) and HPV concordance. METHODS: The HITCH cohort study included young, heterosexual, recently formed, sexually active couples. Questionnaires and genital samples were collected at 0 and 4 months. Samples were tested for HPV DNA by polymerase chain reaction (PCR; Linear Array). VLs of HPV6/11/16/18/31/42/51 were quantified using type-specific real-time PCR. Correlations between VL and type-specific HPV prevalence and incidence were evaluated using multilevel, mixed-effects linear/logistic regression models. RESULTS: We included 492 couples. VLs were higher in penile than vaginal samples. VL at subsequent visits correlated significantly within men (r, 0.373), within women (r, 0.193), and within couples (r range: 0.303-0.328). Men with high VL had more type-specific persistent HPV infections (odds ratio [OR], 4.6 [95% confidence interval {CI}, 2.0-10.5]). High VL in men was associated with prevalent (OR, 5.3 [95% CI, 2.5-11.2]) and incident (OR, 6.7 [95% CI, 1.5-30.7]) type-specific HPV infections in their partner. Women's VL was associated with type-specific HPV prevalence in their partner at the same (OR, 5.9) and subsequent (OR, 4.7) visit. CONCLUSIONS: Persistent HPV infections have limited VL fluctuations. VL between sex partners are correlated and seem predictive of transmission episodes.

Determinants of prevalent human papillomavirus in recently formed heterosexual partnerships: a dyadic-level analysis.

BACKGROUND: We studied features that predict the presence of human papillomavirus (HPV) in a new sexual partnership. METHODS: We analyzed data from the "HPV Infection and Transmission Among Couples Through Heterosexual Activity" (HITCH) Cohort Study of recently formed partnerships ("dyads"). Women aged 18-24 and their male partners were recruited during 2005-2010 in Montreal, Canada. We tested genital swabs for detection of 36 HPV types. We defined HPV in a partnership as the presence of 1 or more HPV types in either or both partners. Using baseline data from 482 dyads, we calculated prevalence ratios to evaluate candidate risk factors. RESULTS: Most women (88%) were unvaccinated. Sixty-seven percent of dyads harbored HPV. For 49% of dyads, both partners were HPV+. HPV was least prevalent in dyads who were in their first vaginal sex relationship (17%) and was virtually ubiquitous in dyads for which both partners had concurrent partners (96%). Dyads that always used condoms with previous partner(s) were 27% (95% confidence interval, 9%-42%) less likely to have HPV. CONCLUSIONS: The finding that condom use limited onward spread to future partners is in support of condom promotion to prevent sexually transmitted infections. Ongoing monitoring of HPV in sexual networks is needed, particularly in populations with suboptimal vaccine coverage.

Sexual transmission of oral human papillomavirus infection among men.

We estimated the prevalence of oral human papillomavirus (HPV) and assessed risk factors among young heterosexual men participating in the HPV Infection and Transmission among Couples through Heterosexual Activity (HITCH) study. Oral and genital HPV samples were collected from 222 men and their female partners who were participating in the HITCH study, a longitudinal cohort on HPV transmission among heterosexual couples. Demographic and behavioral data were collected through self-administered computer questionnaires and biologic samples were tested with the Linear Array for HPV. Outcome measures were overall and type-specific prevalence of oral HPV. The prevalence of oral HPV among men was 7.2% and was higher among men who were ever smokers (12.2%), in nonmonogamous relationships (17.9%), or had a partner with oral (28.6%) and/or genital (11.5%) HPV infection. Moreover, prevalence increased with frequency of oral sex among men whose partner who had a genital infection with the same HPV type. Our results provide further evidence that oral HPV may be transmitted through either oral-oral or oral-genital routes.