Even though antiretroviral treatment is becoming more efficient and available, new HIV infections still occur, and this is particularly evident in the sub-Saharan Africa region. Heterosexual intercourse is still the main mode of HIV transmission in the region, and multiple and concurrent sex partners are arguably crucial for the spread of the epidemic.

Even though antiretroviral treatment is becoming more efficient and available, new HIV infections still occur. This is particularly the case in sub-Saharan Africa.