Epidemiology and risk factors for human papillomavirus infection in a diverse sample of low-income young women

Abstract

Background: Two HPV vaccines prevent infection with HPV-16 and HPV-18, high-risk (cancer-associated) HPV types which together cause approximately 70% of cervical cancers; one vaccine also prevents HPV-6 and HPV-11, which together cause approximately 90% of anogenital warts. Defining type-specific HPV epidemiology in sexually experienced women will help estimate the potential clinical benefits of vaccinating this population.

Objectives: To examine HPV epidemiology in a diverse sample of sexually experienced women, and to determine factors associated with high-risk HPV and vaccine-type HPV (HPV-6, HPV-11, HPV-16 and HPV-18).

Study design: Cross-sectional study of 13-26-year-old women (N=409) who completed a questionnaire and provided a cervicovaginal swab. Swabs were genotyped for HPV using PCR amplification. Logistic regression models were used to determine whether participant characteristics, knowledge, and behaviors were associated with high-risk and vaccine-type HPV.

Results: Most women (68.4%) were positive for >or=1 HPV type, 59.5% were positive for >or=1 high-risk type, 33.1% were positive for >or=1 vaccine-type HPV, and 3.5% were positive for both HPV-16 and HPV-18: none was positive for all four vaccine types. In adjusted logistic regression models, Black race (OR 2.03, 95% CI 1.21-3.41) and lifetime number of male sexual partners (OR 4.79, 95% CI 2.04-11.23 for >or=10 partner vs. <or=1 partner) were independently associated with high-risk HPV infection.

Conclusions: HPV prevalence was very high in this sample of sexually active young women, but <5% were positive for both HPV-16 and HPV-18, suggesting that vaccination could be beneficial for many individual women who are sexually experienced.