High human immunodeficiency virus incidence in a cohort of Rwandan female sex workers.

BACKGROUND: Measurement of human immunodeficiency virus(HIV) incidence among female sex workers in Rwanda is a key part of preparing for HIV prevention trials. METHODS: HIV-negative, nonpregnant female sex workers (N =397) were tested for HIV-1, sexually transmitted infections, and pregnancy quarterly for 12 months, and again at a 1-time year 2 visit. Additional women (N=156) were tested for HIV at baseline and 6 to 12 months thereafter in a parallel study. RESULTS: A total of 19 participants seroconverted during follow-up,with 13 in the first 12 months. The 12-month HIV incidence rate (IR)was 3.5 (95% confidence interval: 1.6, 5.4) per 100 person-years (PY).There was a nonsignificant downward trend from 4.6/100 PY (1.6, 7.7)in the first 6 months to 2.2 (0.1, 4.4) in the second 6 months (IR ratio:2.1 [95% confidence interval: 0.7, 7.8]). The year 2 IR was 2.1 (0.4,3.7), and the HIV IR in the parallel study (in the absence of frequent study visits) was 3.3/100 PY (0, 7.0). HIV testing history, lifetime pregnancies, recent initiation of sex work, gonorrhea, syphilis, and change in reproductive intentions were associated with incident HIV infection. Incidence of pregnancy, herpes simplex virus-type 2,trichomoniasis, gonorrhea, chlamydia, and syphilis per 100 PY were as follows: 26.3 (21.9, 30.7), 8.7 (4.0, 13.4), 16.9 (12.7, 21.1), 12.1 (8.2,15.9), 8.1 (5.1, 11.2), and 6.2 (3.7, 8.7). CONCLUSIONS: The HIV/sexually transmitted infections burden int his group was high. HIV IR was highest in the first 6 months of the cohort, and in the parallel study in which there were no risk-reduction procedures. HIV prevention and family planning interventions are needed.

The epidemiology of human papillomavirus infection in HIV-positive and HIV-negative high-risk women in Kigali, Rwanda.

BACKGROUND: The prevalence, incidence and persistence of human papillomavirus (HPV) types in sub-Saharan Africa are not well established. The objectives of the current study are to describe (predictors of) the epidemiology of HPV among high-risk women in Kigali, Rwanda. METHODS: HIV-negative, high-risk women were seen quarterly for one year, and once in Year 2. HIV serostatus, clinical, and behavioral information were assessed at each visit, HPV types at Month 6 and Year 2, and other sexually transmitted infections (STI) at selected visits. HPV prevalence was also assessed in HIV-positive, high-risk women. RESULTS: Prevalence of any HPV was 47.0% in HIV-negative women (median age 25 years) compared to 72.2% in HIV-positive women (median age 27 years; OR 2.9, 95% CI 1.9-4.6). Among HIV-negative women, cumulative incidence of high-risk (HR)-HPV was 28.0% and persistence 32.0% after a mean period of 16.6 and 16.9 months, respectively. Prior Chlamydia trachomatis and Neisseria gonorrhoeae infection, concurrent low-risk (LR)-HPV infection and incident HSV-2 were associated with HR-HPV prevalence among HIV-negative women; prior C. trachomatis infection and co-infection with LR-HPV and HPV16-related HPV types with HR-HPV acquisition. HPV16-related types were the most prevalent and persistent. CONCLUSIONS: High HPV prevalence, incidence and persistence were found among high-risk women in Kigali. HPV52 had the highest incidence; and, together with HPV33 and HPV58, were strongly associated with acquisition of other HR-HPV types in HIV-negative women.

Risk Factor Detection as a Metric of STARHS Performance for HIV Incidence Surveillance Among Female Sex Workers in Kigali, Rwanda.

BACKGROUND: The epidemiologic utility of STARHS hinges not only on producing accurate estimates of HIV incidence, but also on identifying risk factors for recent HIV infection. METHODS: As part of an HIV seroincidence study, 800 Rwandan female sex workers (FSW) were HIV tested, with those testing positive further tested by BED-CEIA (BED) and AxSYM Avidity Index (Ax-AI) assays. A sample of HIV-negative (N=397) FSW were followed prospectively for HIV seroconversion. We compared estimates of risk factors for: 1) prevalent HIV infection; 2) recently acquired HIV infection (RI) based on three different STARHS classifications (BED alone, Ax-AI alone, BED/Ax-AI combined); and 3) prospectively observed seroconversion. RESULTS: There was mixed agreement in risk factors between methods. HSV-2 coinfection and recent STI treatment were associated with both prevalent HIV infection and all three measures of recent infection. A number of risk factors were associated only with prevalent infection, including widowhood, history of forced sex, regular alcohol consumption, prior imprisonment, and current breastfeeding. Number of sex partners in the last 3 months was associated with recent infection based on BED/Ax-AI combined, but not other STARHS-based recent infection outcomes or prevalent infection. Risk factor estimates for prospectively observed seroconversion differed in magnitude and direction from those for recent infection via STARHS. CONCLUSIONS: Differences in risk factor estimates by each method could reflect true differences in risk factors between the prevalent, recently, or newly infected populations, the effect of study interventions (among those followed prospectively), or assay misclassification. Similar investigations in other populations/settings are needed to further establish the epidemiologic utility of STARHS for identifying risk factors, in addition to incidence rate estimation.