MOTHER-TO-CHILD TRANSMISSION OF HIV-1 IN CONGO, CENTRAL-AFRICA

Objective: To assess the risk of mother-to-child transmission of HIV-1 in a central African population and to study maternal factors associa ted with perinatal transmission. Design: Prospective cohort study of i nfants born to HIV-1-positive women and controls born to HIV-1-negativ e women enrolled sequentially in two prenatal clinics and one maternit y hospital in Brazzaville, Congo. Subjects and methods: A total of 118 exposed and 208 control infants were followed from birth for at least 2 years. Assessment of infection in children and computation of trans mission rate were made according to the European Economic Community/Wo rld Health Organization Ghent guidelines (1992). Results: The transmis sion rate was 40.4% [95% confidence interval (CI), 30.7-50.1]. Materna l age, parity, history of adverse pregnancy outcome or history of dece ased children were not associated with transmission. However, independ ently, women whose relationship with their infant's father was less th an 1 year, or women who had symptoms of HIV-1 during pregnancy had an increased risk of transmission [adjusted odds ratios, 11.1 (95% CI, 2. 4-50.2) and 10.3 (95% CI, 2.9-37.1), respectively]. Conclusion: The tr ansmission rate observed in Congo is in the upper range of the rates r eported in Africa. The uneven distribution of cofactors for perinatal transmission, such as the presence of symptoms of HIV disease during p regnancy, may explain some of the variation observed across studies.