[coldtea]

>How many strictly heterosexual couples have been infected with HIV in the history of mankind?

Several tens of millions (most of them in Africa), why?

[1000units]

Do you have any statistics on this you can refer me to? The CDC estimates the transmission risk for receptive PIV intercourse to be about 8 in 10,000 exposures (0.08%). It's half that for the insertive partner.