Prevalence and incidence of genital warts and cervical Human Papillomavirus infections in Nigerian women.

BACKGROUND: Genital warts are important causes of morbidity and their prevalence and incidence can be used to evaluate the impact of HPV vaccination in a population. METHODS: We enrolled 1020 women in a prospective cohort study in Nigeria and followed them for a mean (SD) of 9 (4) months. Nurses conducted pelvic examinations and collected ectocervical samples for HPV testing. We used exact logistic regression models to identify risk factors for genital warts. RESULTS: The mean age of study participants was 38 years, 56% (535/962) were HIV-negative and 44% (427/962) were HIV-positive. Prevalence of genital warts at enrolment was 1% (4/535) among HIV-negative women, and 5% (23/427) among HIV-positive women. Of 614 women (307 HIV negative and 307 HIV positive women) for whom we could compute genital wart incidence, it was 515 (95% CI:13-2872) per 100,000 person-years in HIV-negative and 1370 (95% CI:283-4033) per 100,000 person-years in HIV-positive women. HIV was associated with higher risk of prevalent genital warts (OR:7.14, 95% CI:2.41-28.7, p < 0.001) while higher number of sex partners in the past year was associated with increased risk of incident genital warts (OR:2.86, 95% CI:1.04-6.47. p = 0.04). HPV11 was the only HPV associated with prevalent genital warts in this population (OR:8.21, 95% CI:2.47-27.3, p = 0.001). CONCLUSION: Genital warts are common in Nigeria and our results provide important parameters for monitoring the impact of future HPV vaccination programs in the country. HIV infection and number of sexual partners in past year were important risk factors for prevalent and incident genital warts respectively.

Clearance of Type-Specific, Low-Risk, and High-Risk Cervical Human Papillomavirus Infections in HIV-Negative and HIV-Positive Women.

Purpose There is a dearth of data on clearance of cervical human papillomavirus (HPV) infection among women in West Africa. We examined the clearance of low-risk (lr) and high-risk (hr) cervical HPV infections, and the factors associated with these measures in HIV-negative and HIV-positive women. Methods We studied 630 Nigerian women involved in a study of HPV infection using short polymerase chain reaction fragment-10 assay and line probe assay-25. Research nurses used a cervical brush to collect samples of exfoliated cervical cells from all the study participants. Cox proportional hazards models were used to estimate associations between HIV and HPV infections. Results The mean age of the study participants was 38 (standard deviation, ± 8) years; 51% were HIV positive. The rate of clearing any HPV infection was 2.0% per month among all women in the study population, 2.5% per month among HIV-negative women, and 1.6% per month, among HIV-positive women. The clearance rate per 1,000 person-months of observation for any lrHPV infection and any hrHPV infection were 9.21 and 8.83, respectively, for HIV-negative women, and 9.38 and 9.37, respectively, for HIV-positive women. In multivariate models, the hazard ratios for HIV-positive compared with HIV-negative women were 0.85 (95% CI, 0.51 to 1.43; P = .55) and 0.95 (95% CI, 0.54 to 1.65; P = .85) for cleared infections with any lrHPV and any hrHPV, respectively. The hazard ratio for HIV-positive compared with HIV-negative women was 0.39 (95% CI, 0.17 to 0.88; P = .02) for cleared infections with any multiple HPV and 0.13 (95% CI, 0.03 to 0.58; P = .007) for cleared infections with multiple hrHPV. Conclusion In this study population, we observed that HIV-positive women were less likely to clear infections with multiple hrHPV types.

Persistent Low-Risk and High-Risk Human Papillomavirus Infections of the Uterine Cervix in HIV-Negative and HIV-Positive Women.

BACKGROUND: The prevalence, persistence, and multiplicity of human papillomavirus (HPV) infection appears different comparing HIV-positive to HIV-negative women. In this study, we examined prevalent, persistent, and multiple low- and high-risk cervical HPV infections in HIV-negative and HIV-positive women. METHODS: We studied 1,020 women involved in a study of HPV infection using SPF25/LiPA10. Two study visits were scheduled, at enrollment and 6 months afterward. At each study visit, research nurses used a cervical brush to collect samples of exfoliated cervical cells from the cervical os, from all the study participants. Exact logistic regression models were used to estimate associations between HIV and HPV infections. RESULTS: The mean (SD) age of the study participants was 38 (8) years, 56% were HIV-negative and 44% were HIV-positive. Among HIV-negative women at baseline, single low-risk HPV (lrHPV) infections occurred in 12%; multiple lrHPV in 2%; single high-risk human papillomavirus (hrHPV) infections in 9%, and multiple hrHPV infections in 2%. Single lrHPV infections were persistent in 6%, but there was no persistent multiple lrHPV infections. Single hrHPV infections were persistent in 4% while multiple hrHPV infections were persistent in 0.3%. Among HIV-positive women at baseline, single lrHPV infections occurred in 19%, multiple lrHPV in 6%, single hrHPV infections in 17%, and multiple hrHPV infections occurred in 12%. Single lrHPV infections were persistent in 9%, multiple lrHPV infections in 0.6%, single hrHPV infections in 13%, while multiple hrHPV were persistent in 3%. Prevalent, persistent, and multiple infections were more common in HIV-positive women, compared to HIV-negative women. In multivariate models adjusted for age, marital status, socioeconomic status, age at sexual initiation, and douching, the odds ratios comparing HIV-positive to HIV-negative women, were 2.09 (95% CI 1.47-2.97, p < 0.001) for prevalent lrHPV, 1.26 (95% CI 0.66-2.40, p 0.47) for persistent lrHPV infections, 3.38 (95% CI 2.34-4.87, p < 0.001) for prevalent hrHPV, and 4.49 (95% CI 2.26-8.91, p < 0.001) for persistent hrHPV infections. CONCLUSION: HIV infection was associated with higher prevalence of lrHPV, hrHPV, and persistence hrHPV infections, but not persistent lrHPV infections.