The chances of HIV being transmitted from an HIV+ person to an HIV-negative person depends on the type of contact. HIV is most easily transmitted through unprotected (no condoms) anal sex, unprotected vaginal sex, and sharing injection drug equipment.
Oral sex has been shown to be less risky than these activities, but it is not risk-free. It is also possible to get other sexually-transmitted diseases (STDs), such as syphilis, herpes, and gonorrhea through oral sex.
Studies on the Risks of Oral Sex
Even though oral sex is a lower-risk activity, people have reportedly become infected with HIV in this way. A number of studies have tried to determine the exact level of risk of oral sex, but it can be difficult to get accurate information from study participants. Since oral sex is not the only sexual activity for most people, it is also difficult to single out oral sex as the definite way HIV was transmitted. Because of these issues, different studies have reported different levels of risk ranging from less than 1% to about 8%.
The take home message of these studies is that oral sex carries a small but real risk.
Tips for Safer Oral Sex
Oral sex is more risky if you or your partner have an untreated STD, bad oral hygiene (bleeding gums, ulcers, gum disease), or take ejaculate (cum) in the mouth. There are things you can do to reduce the risk associated with oral sex:
Taking Care of Yourself
Any type of sexual activity with an infected person carries a risk of HIV transmission. While the risk of becoming infected through unprotected oral sex is lower than that of unprotected anal or vaginal sex, bad oral hygiene and taking cum in your mouth makes oral sex more risky.
If you or your partner is HIV+, you should decide what steps to take to make all types of sex as safe as possible. If you would like to discuss these issues, see a sex educator or health care provider at your local AIDS service organization or treatment center.