Donating blood or body parts does NOT put you at risk of HIV infection. The majority of these cases have been identified amongst men who have sex with men. Anyone who has unsafe sex or shares a needle and syringe with someone infected with HIV is at risk of HIV infection. Unsafe sex is any sexual activity that allows blood, semen or vaginal fluids to pass from one person to another. Semen can enter a woman's body through breaks in the fine lining of the vagina.
Vaginal fluids can enter a man's body through the head of the penis.
The risks for anal sex are greater than for vaginal sex because of the potential for the lining of the anus or rectum to tear. Semen can enter the body through these tears. Blood or secretions can enter through the head of the penis. There have been a few cases of infection through oral sex, although the risk of HIV transmission is much lower than for unprotected vaginal or anal sex. Semen or vaginal fluids can enter the body through small cuts or scrapes in the mouth.