Human papillomaviruses and cervical cancer in Bangkok. III. The role of husbands and commercial sex workers.

Between September 1991 and September 1993, husbands of women with and without cervical neoplasia and commercial sex workers in one brothel and one massage parlor in Bangkok, Thailand, were interviewed; serologic tests for sexually transmitted infections were performed; and cervical and penile scrapings were tested for human papillomavirus (HPV) DNA. The risks of cervical carcinoma in monogamous women and of oncogenic HPV in their husbands were associated with the men's having unprotected intercourse with prostitutes. The prevalence of oncogenic HPV was higher in commercial sex workers than in women attending gynecologic and family planning clinics. Oncogenic HPV prevalence declined with age in human immunodeficiency virus (HIV)-negative, but not in healthy HIV-positive, commercial sex workers and was weakly associated with hepatitis B antigenemia, suggesting that persistence of HPV infection is due to subtle changes in immunity. Associations of HPV with recent pregnancy and oral contraceptive use suggest that hormonal factors may increase the risk of cervical neoplasia by enhancing persistence of HPV infection. The prevalence of high-grade squamous intraepithelial lesions was strongly related to oncogenic HPV types and weakly to HIV infection only in their presence. Commercial sex workers in Bangkok are reservoirs of oncogenic HPV, and cervical cancer in monogamous Thai women develops in part as a result of transmission of these viruses to them by their husbands from prostitutes.