Nversion to determine whether there were differences in ulcer occurrence by randomization group in the absence of study drug. All analyses were conducted in SAS 9.3 or Stata 12.Results Study participantsCharacteristics of the 2,499 iPrEx participants have been described previously. [13] Briefly, all participants were born male and 313 (13.0 ) identified as transgender or as women. The mean age at
T among participants living in Peru (46.0 ), Brazil (37.8 ), and Ecuador (37.3 ), with lower prevalence among participants living in Thailand (6.4 ), South Africa (17.6 ), and the United States (27.1 ; P,0.001). Randomization group was not associated with HSV-2 prevalence at baseline (P = 0.44). In multivariable analysis, all factors remained significantly associated with HSV-2 prevalence with the
Used acyclovir or valacyclovir during study follow-up.HSV-2 prevalenceOf the 2,499 participants, 1383 (55.3 ) tested negative for HSV-2 at baseline, 892 (35.7 ) tested positive, 223 (8.9 ) had indeterminate tests, and one test was not done. Of the 223 with indeterminate tests at baseline, 114 (51.1 ) tested positive for HSV-2 infection at some point during follow-up. Factors associated with testin