14th International AIDS Conference Barcelona, Spain — July 7-12, 2002

Int Conf AIDS. 2002 Jul 7-12;14:Abstract No. TuOrB1177

BACKGROUND: We analyzed individual patient data from randomized, placebo-controlled clinical trials to estimate the contribution of breastfeeding to the overall risk of mother-to-child transmission (MTCT) of HIV-1, to clarify the timing of breastfeeding transmission, and to identify determinants of late postnatal transmission (LPT) (infected after 4 weeks of age with prior negative test(s) at or after 4 weeks) via breastfeeding.

METHODS: Eligible trials were completed (or ongoing, if enrollment was completed) and conducted where breastfeeding was common; included a minimal sequential laboratory follow-up (e.g., DNA/RNA PCR) of 2 or more scheduled diagnostic tests by 3 months of age, and, if follow-up continued, 2 additional tests between 3 and 12 months; and provided regular assessment of infant feeding modality. Uniform definitions of HIV-1 infection status of the children were applied across studies. Data for children born before January 2000 are being analyzed.

RESULTS: 9 of 10 eligible trials agreed to participate. Of 5240 children with available data, 1509 are being evaluated in the primary analysis of LPT (singletons, enrolled in non-intervention arms of trials, breastfed, with HIV-1 diagnostic testing). Of these 1509, the mean (median) duration of follow-up was 12.2 (14.7) months and of breastfeeding was 6.8 (3.5) months. 378/1509 were definitively infected (25% overall transmission rate). Of the 378, 179 could be categorized according to the timing of infection; there were 115 (64%) early infections (before 4 weeks of age) and 64 (36%) LPTs.

CONCLUSIONS: LPTs represent a substantial proportion of HIV-1 transmission of known timing. The large sample size and the application of uniform definitions across trials in this meta-analysis should provide more reliable and precise estimates than previous studies of the risk and timing of late postnatal MTCT of HIV-1 through breastfeeding.

Presenting author: J S Read

1National Institutes of Health, PAMA-CRMC-NICHD, National Institutes of Health, 6100 Executive Blvd., Room 4B11F, Bethesda, MD 20892, United States

2Institute of Child Health, London, United Kingdom

3Universite Victor Segalen Bordeaux 2, Bordeaux, France

020708
TuOrB1177

Copyright © 2002 - International AIDS Society (IAS). Reproduction of this abstract (other than one copy for personal reference) must be cleared through the IAS.