*Longitudinal samples from women in the HIV Prevention Trials Network (HIVNET) 012 trial and HIVNET 012 follow-up study were analyzed using the BED-Capture enzyme immunoassay (BED) [8] and an antibody avidity assay based on the BioRad 1/2 + O ELISA test (avidity) [9].

Baseline samples were collected near the time of delivery in the HIVNET 012 trial. Data from the baseline samples is shaded, as well as data from follow-up visits where a woman was pregnant (see Methods). Results from the BED and avidity assays that indicate recent infection (BED: results OD-n<0.8; for avidity: results <40%) are shown in bold text. Results are shown for baseline samples (obtained in the HIVNET 012 trial from the time of delivery or 7 days after delivery), and for samples collected 3, 4, and 5 years later (3Y, 4Y, 5Y). ^aThese women were identified as falsely incident at follow-up using the BED assay; two of these women had subtype A infection and two had subtype D infection. ^bThese women may have had incident infection in the HIVNET 012 trial. ^cThese samples were obtained when women were on antiretroviral therapy.