CD4 and sexually transmitted disease: The CD4 HIV/ART, Eaton, Goals, Granich, and STI-HIV Interaction models used estimates of the number of adults starting treatment in South Africa in each year between 2001 and 2011 from [45], and the Fraser and STDSIM models used existing calibrations to ART coverage levels in the Western Cape and KwaZulu-Natal Provinces, respectively.