My favourite quote on this is from Stephen fry, who has done a great deal of work with AIDS in Africa
"There was a time when [Uganda] had the highest incidence rates of HIV/AIDs in the world but through an amazing initiative called ABC:
Abstinence,
Be faithful
Correct use of condoms
Those three, and I'm not denying that abstinence is a very good way of not getting AIDs it really is, it works; so does being faithful but so do condoms and do not deny it!"