Herpes simplex type II and Mycoplasma genitalium as risk factors for heterosexual HIV transmission: report from the heterosexual HIV transmission study.
Two hundred twenty-four human immunodeficiency virus (HIV) discordant couples (one HIV negative, one HIV positive) were compared with 78 seroconcordant heterosexually infected couples with HIV with regard to sexually transmitted diseases. Serologic testing and cultures were used to determine exposure of participants to sexually transmitted pathogens. These data were compared with HIV concordance of partners to investigate possible risk factors for HIV transmission. Syphilis, chlamydia, and hepatitis B virus (HBV) serologies did not distinguish between concordant and discordant couples nor did cultures for Neisseria gonorrhoeae and Trichomonas or Chlamydia enzyme immunoassay (EIA). Risk of transmission increased with positive serologies for herpes simplex virus (HSV)-2 (P = 0.002), cytomegalovirus (CMV) (P = 0.04), and Mycoplasma genitalium (P = 0.01), but not with Mycoplasma fermentans or Mycoplasma penetrans. Cytomegalovirus was not a significant risk factor when controlled for HSV-2 status. Examination by partner status showed increased risk of concordance with: HSV-2 positive serology in both partners (odds ratio [OR] = 3.14; confidence interval [CI] = 1.62-6.09; P = 0.007); HSV-2 in female secondary partner (OR = 2.10; CI = 1.12-3.93; P = 0.02) or the male primary partner (OR = 2.15; CI = 1.15-4.02; P = 0.017); M. genitalium antibody in both partners (OR = 3.44; CI = 1.68-7.04; P < 0.001); M. genitalium antibody in the primary male partner (OR = 2.51, CI = 1. 27-4.91; P = 0.008) and M. genitalium antibody in the secondary female partner (OR = 2.52; CI = 1.21-5.23; P = 0.01). These data support the role of HSV-2 in transmission of HIV and, for the first time, suggest a role for M. genitalium as an independent risk factor.