. . . According to the San Francisco-based National Sex Forum: “It is not sex that causes AIDS, but the migration of the virus from one person to another. If you do not come into contact with your partner’s bodily fluids, you will not come in contact with the disease.” With this in mind, you can relax in the knowledge that if you engage in heterosexual intercourse, latex condoms are very effective in providing a physical barrier against genital transmission of AIDS and other STDs. For gays and heterosexuals who enjoy anal sex, however, even wearing a condom is no guarantee. The best advice is to avoid anal sex altogether unless you are 100 percent positive that you and your partner are safe.