HPTN Bibliographic Record

Chen YQ, Young A, Brown ER, Chasela CS, Fiscus SA, Hoffman IF, Valentine M, Emel L, Taha TE, Goldenberg RL, Read JS. Population Attributable Fractions for Late Postnatal Mother-to-Child Transmission of HIV-1 in Sub-Saharan Africa. JAIDS. 2010, 54: 311-16 PMCID: 3086731.
Objectives: Assess population attributable fractions (PAFs) for late postnatal transmission (LPT) of HIV-1 in a cohort of HIV-1-exposed infants. Methods: We used data established from a risk factor analysis of LPT (negative HIV-1 results through the 4-6 week visit, but positive assays thereafter through the 12-month visit) from a perinatal clinical trial conducted in 3 sub-Saharan countries. PAFs were calculated as the proportions of excess LPTs attributed to identified risk factors. Results: For the cohort of 1317 infants, 206 (15.6%) had only low maternal CD4+ counts (<200 cells/mm3), 332 (25.2%) had only high maternal plasma viral loads (VLs) (>50,000 copies/mL), and 81 (6.2%) had both low CD4+ counts and high VLs. Their PAFs were 26.0% [95% confidence interval (CI): 12.0% to 36.0%], 37.0% (95% CI: 22.0% to 51.0%), and 16.0% (95% CI: 6.0% to 25.0%), respectively. Conclusions: Our PAF analysis illustrates the public health impact of the substantial proportion of LPTs accounted for by high-risk women with both low CD4+ counts and high VLs. In light of these results, access to and use of antiretroviral therapy by high-risk HIV-1-infected pregnant women is essential. Additional strategies to reduce LPT for those not meeting criteria for antiretroviral therapy should be implemented.