Human Papillomavirus in Male Clients of Female Sex Workers in Peru

Background: The prevalence of high risk Human Papillomavirus (HR-HPV) in Female Sex Workers (FSW) in Callao, Peru is more than 3 times higher than the prevalence in the general local population. Prevalence of HR-HPV infections among male clients of FSW has not previously been reported. Consistent condom use decreases risk of HPV infection, but heterosexual transmission has been reported even with condom use.

Methods: 150 males soliciting sexual intercourse in sex-work venues in Callao, Peru were anonymously enrolled. Demographic and behavioral questionnaires were administered by study personnel. FSW were trained to assist male clients to obtain swabs of the penis prior to and immediately following condom-protected sexual intercourse for HPV type-specific PCR processing (including 13 HR-HPV types AND 19 low-risk types). Urine samples were screened for gonorrhea and chlamydia. A paired t-test was used to compare the number of HPV types detected in samples collected pre- and post-intercourse, and logistic regression was used to evaluate potential correlates of infection.

Results: Of 148 genital samples collected prior to intercourse, 65.5% had >=1 HPV type detected, and 41.6% had >=1 HR-HPV type detected; 58.1% of HR-HPV-positive samples had ≥2 HR-HPV types. The most prevalent HR-HPV types were 51 (12.8%), 16 (11.5%), 58 (10.8%), and 59 (9.5%). Of 62 clients with HR-HPV, 19 (30.6%) were positive for HPV-16 or HPV-18 - types included in the quadrivalent HPV vaccine. Of samples collected following intercourse (n=147), 71.4% had >=1 HPV type detected. The mean number of HPV types detected prior to sex increased following intercourse (1.9 to 2.5; p-value <0.01). No demographic or sexual behavior variables were statistically significantly associated with detection of HPV pre- or post-intercourse. No cases of gonorrhea and 6 (4.1%) cases of chlamydia were detected.

Conclusion: Despite low prevalence of other STI and acceptance and use of condoms, male clients of FSW in Callao, Peru had a high prevalence of HPV. Increased detection of HPV DNA following condom protected intercourse reflects transfer of HPV DNA from FSW, and may indicate potential for HPV transmission between FSW and male clients despite reported condom use.