Valley-Omar, Ziyaad.Sibeko, Sengeziwe.Anderson, Jeffrey A.Goodier, Sarah A.Werner, Lise.Arney, Leslie.Naranbhai, Vivek.Treurnicht, Florette K.Abrahams, Melissa-Rose.Bandawe, Gama P.Swanstrom, Ronald.Abdool Karim, Salim Safurdeen.Abdool Karim, Quarraisha.Williamson, Carolyn.2012-11-232012-11-2320112011Valley-Omar, Z. et al. 2012. CAPRISA 004 tenofovir microbicide trial: no impact of tenofovir gel on the HIV transmission bottleneck. J Infect Dis. 206 (1) pp. 35-40.0022-1899http://dx.doi.org/ 10.1093/infdis/jis305http://hdl.handle.net/10413/7959Alterations of the genital mucosal barrier may influence the number of viruses transmitted from a human immunodeficiency virus–infected source host to the newly infected individual. We used heteroduplex tracking assay and single-genome sequencing to investigate the effect of a tenofovir-based microbicide gel on the transmission bottleneck in women who seroconverted during the CAPRISA 004 microbicide trial. Seventy-seven percent (17 of 22; 95% confidence interval [CI], 56%–90%) of women in the tenofovir gel arm were infected with a single virus compared with 92% (13 of 14; 95% CI, 67%–>99%) in the placebo arm (P = .37). Tenofovir gel had no discernable impact on the transmission bottleneck.enHIV infections--Treatment.Tenofovir.Tenofovir microbicide trials.Peer reviewed journal article