Nt HSV-2 infection in iPrEx was receptive anal intercourse without a condom, a finding that has been reported in several studies of behavioral risk factors for HSV-2 acquisition in MSM. [18,19,20] The rectal mucosa and cervicovaginal mucosa may differ in their susceptibility to HSV-2 infection. Additionally, although oral dosing of tenofovir achieves drug concentrations that are 20?00 times higher