Safe Sex > HIV/AIDS Questions and Answers: What is AIDS? AIDS stands for acquired immunodeficiency syndrome. A diagnosis of AIDS is made by a physician using certain clinical or laboratory standards. What causes AIDS? AIDS is caused by infection with a virus called human immunodeficiency virus (HIV). This virus is passed from one person to another through blood-to-blood and sexual contact. In addition, infected pregnant women can pass HIV to their babies during pregnancy or delivery, as well as through breast feeding. People with HIV have what is called HIV infection. Most of these people will develop AIDS as a result of their HIV infection. What body fluids transmit HIV? These body fluids have been proven to spread HIV: Blood Semen Vaginal fluid Breast milk Other body fluids containing blood Can I get HIV from kissing on the cheek? HIV is not casually transmitted, so kissing on the cheek is very safe. Even if the other person has the virus, your unbroken skin is a good barrier. No one has become infected from such ordinary social contact as dry kisses, hugs, and handshakes. Can I get HIV from open-mouth kissing? Open-mouth kissing is considered a very low-risk activity for the transmission of HIV. However, prolonged open-mouth kissing could damage the mouth or lips and allow HIV to pass from an infected person to a partner and then enter the body through cuts or sores in the mouth. Because of this possible risk, the CDC recommends against open-mouth kissing with an infected partner. Can I get HIV from performing oral sex? Yes, it is possible for you to become infected with HIV through performing oral sex. There have been a few cases of HIV transmission from performing oral sex on a person infected with HIV. While no one knows exactly what the degree of risk is, evidence suggests that the risk is less than that of unprotected anal or vaginal sex. Blood, semen, pre-seminal fluid, and vaginal fluid all may contain the virus. Cells in the mucous lining of the mouth may carry HIV into the lymph nodes or the bloodstream. The risk increases if you have cuts or sores around or in your mouth or throat; if your partner ejaculates in your mouth; or if your partner has another sexually transmitted disease (STD). If you choose to have oral sex, and your partner is male,use a latex condom on the penis; or if you or your partner is allergic to latex, plastic (polyurethane) condoms can be used. Research has shown the effectiveness of latex condoms used on the penis to prevent the transmission of HIV. Condoms are not risk-free, but they greatly reduce your risk of becoming HIV-infected if your partner has the virus. If you choose to have oral sex, and your partner is female, use a latex barrier (such as a dental dam or a cut-open condom that makes a square) between your mouth and the vagina. Plastic food wrap also can be used as a barrier. The barrier reduces the risk of blood or vaginal fluids entering your mouth. Can I get HIV from someone performing oral sex on me? Yes, it is possible for you to become infected with HIV through receiving oral sex. If your partner has HIV, blood from their mouth may enter the urethra (the opening at the tip of the penis), the vagina, the anus, or directly into the body through small cuts or open sores. While no one knows exactly what the degree of risk is, evidence suggests that the risk is less than that of unprotected anal or vaginal sex. If you choose to have oral sex, use a latex condom on the penis; or if you or your partner is allergic to latex, a plastic (polyurethane) condom can be used. Can I get HIV from having vaginal sex? Yes, it is possible to become infected with HIV through vaginal intercourse. In fact, it is the most common way the virus is transmitted in much of the world. HIV can be found in the blood, semen, pre-seminal fluid, or vaginal fluid of a person infected with the virus. The lining of the vagina can tear and possibly allow HIV to enter the body. Direct absorption of HIV through the mucous membranes that line the vagina also is a possibility. The male may be at less risk for HIV transmission than the female through vaginal intercourse. However, HIV can enter the body of the male through his urethra (the opening at the tip of the penis) or through small cuts or open sores on the penis. Risk for HIV infection increases if you or a partner has a sexually transmitted disease (STD). See also "Is there a connection between HIV and other sexually transmitted diseases?" If you choose to have vaginal intercourse, use a latex condom to help protect both you and your partner from the risk of HIV and other STDs. Studies have shown that latex condoms are very effective, though not perfect, in preventing HIV transmission when used correctly and consistently. If either partner is allergic to latex, plastic (polyurethane) condoms for either the male or female can be used. Can I get HIV from anal sex? Having unprotected (without a condom) anal sex is considered to be a very risky behavior. If people choose to have anal sex, they should use a latex condom. Most of the time, condoms work well. However, condoms are more likely to break during anal sex than during vaginal sex. Thus, even with a condom, anal sex can be risky. A person should use a water-based lubricant in addition to the condom to reduce the chances of the condom breaking. How effective are latex condoms in preventing HIV? Studies have shown that latex condoms are highly effective in preventing HIV transmission when used consistently and correctly. These studies looked at uninfected people considered to be at very high risk of infection because they were involved in sexual relationships with HIV-infected people. The studies found that even with repeated sexual contact, 98-100 percent of those people who used latex condoms correctly and consistently did not become infected. Is there a connection between HIV and other sexually transmitted diseases? Yes. Having a sexually transmitted disease (STD) can increase a person's risk of becoming infected with HIV, whether the STD causes open sores or breaks in the skin (e.g., syphilis, herpes) or does not cause breaks in the skin (e.g., chlamydia, gonorrhea). If the STD infection causes irritation of the skin, breaks or sores may make it easier for HIV to enter the body during sexual contact. Even when the STD causes no breaks or open sores, the infection can stimulate an immune response in the genital area that can make HIV transmission more likely. In addition, if an HIV-infected person also is infected with another STD, that person is three to five times more likely than other HIV-infected persons to transmit HIV through sexual contact. Not having (abstaining from) sexual intercourse is the most effective way to avoid STDs, including HIV. How can I get more information about AIDS? CDC operates a free telephone service that is available 24-hour, 7 days a week. You can contact the CDC National STD and AIDS Hotlines at 1-800-342-2437. Service for Spanish-speaking audiences and the Deaf are also available. Where can I get testing for AIDS? To find a Family Planning Center nearest you click here or call 1-866-SAFETEENS. Services to teens under age 18 are free and confidential. Reprinted February 27, 2002 Centers for Disease Control & Prevention National Center for HIV, STD, and TB Prevention Divisions of HIV/AIDS Prevention. < Back to Safe Sex Main Page