Incident HIV-1 infection in a cohort of young women in Butare, Rwanda.
OBJECTIVE
To determine the incidence of HIV-1 infection and associated risk factors among young, seronegative, and sexually active women in a mixed rural and urban population in southern Rwanda.


METHODS
A prospective cohort study.


METHODS
Between October 1991 and April 1993, we completed a 2-year follow-up survey among HIV-1-seronegative women aged < or = 30 years at the time of their initial HIV-1 screening during pregnancy. All women aged < or = 25 years and a randomly selected sample of 26-30-year olds were invited to participate from five prenatal clinics in the Butare region. The interview focused on potential risk factors for HIV-1 acquisition during the 2-year interval between blood collection.


RESULTS
Out of 1524 women selected, 1150 (75%) participated in the follow-up survey. The 2-year incidence of HIV-1 infection was 2.7% [95% confidence interval (CI), 1.8-3.9]. Teenage women were at the highest risk (incidence, 10.5%; 95% CI, 5.2-19.4), with incidence leveling off with increasing age (P < 0.001). Women who began sexual activity recently were also at higher risk; the lowest risk category consisted of women aged 26-30 years with 5 or more years of sexual experience. The more urban the geographic residence of the woman, the more likely she was to have acquired HIV-1 infection (P < 0.001). In the urban and peri-urban zones, the poorest women were at significantly higher risk of incident HIV-1 infection than women reporting higher household income. In a multivariate analysis, young maternal age, marital status (being single, divorced or widowed), multiple sexual partners, and a history of sexually transmitted diseases remained strongly associated with incident HIV-1 infection. Geographic residence, hormonal contraception, and receipt of injections were no longer significantly associated with incident HIV-1 infection when these other factors were accounted for simultaneously.


CONCLUSIONS
Among young Rwandan women, the early years of sexual activity are particularly dangerous for acquisition of HIV-1 infection. Interventions should focus on young teenagers before they become sexually active.
Department of Epidemiology, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland.
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Bulterys
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Chao
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Habimana
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Dushimimana
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Nawrocki
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Saah
D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology*; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D015331:Cohort Studies; D003710:Demography; D005260:Female; D005500:Follow-Up Studies; D018023:HIV Seronegativity; D015497:HIV-1; D006801:Humans; D015994:Incidence; D011247:Pregnancy; D011897:Random Allocation; D012307:Risk Factors; D012424:Rural Population; D012432:Rwanda / Q000453:epidemiology; D012725:Sexual Behavior; D014505:Urban Population; D014930:Women