O column totals due to missing data. doi:10.1371/journal.pone.0091513.tparticipants reported taking over 90 of study drug doses, drug was detectable in the blood specimens of only 50 of participants tested in a random subsample.[13] Although we did not observe an effect of FTC/TDF even after accounting for drug levels, it may be that oral FTC/TDF will be shown to have an impact on HSV-2 incidenc