How Is HIV Transmitted

It is not uncommon to wonder how you can get HIV. The human immunodeficiency virus (HIV) can be transmitted through anal, penile-vaginal, and oral intercourse. With this said, of these activities, anal intercourse (also known as “anal sex”) puts someone at the highest risk for transmission of HIV by a large margin. Oral intercourse is the lowest-risk activity listed.

Read this articles to understand your odds of contracting HIV.

Other factors can increase the risk of HIV transmission, such as a herpes infection and the presence of genital lesions or ulcerations. It is important to remember that condoms are very effective at reducing the risk of HIV. Typical use of condoms (which is imperfect) still leads to an 80 to 85 percent risk in reduction of HIV transmission. Latex and polyurethane condoms are impenetrable to HIV viral particles, but it is important that condoms are used properly to help reduce the risk of HIV transmission.

Kissing, skin-to-skin contact, and contact with tears, feces, urine, and sweat are not risk factors for transmission of HIV. Because such contact does not involve blood, the theoretical risk of transmission is zero percent.

Risk rates for HIV transmission

The exact transmission rates are not known with total certainty. However, among heterosexual couples, the approximate rates of HIV transmission are as follows:

  • About 1 in 200 sexual acts, for receptive anal intercourse
  • About 1 in 1000 sexual acts, for receptive vaginal intercourse
  • About 5 in 10,000 sexual acts, for insertive vaginal intercourse

Additionally, receiving oral sex from an HIV-infected person carries a risk of only about 1 in 10,000 sexual acts. As you can see, the risk of receiving oral sex and performing penetrative vaginal sex are significantly lower than anal intercourse (receptive or insertive).

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Workshop summary: scientific evidence on condom effectiveness for sexually transmitted diseases (STD) prevention. National Institute of Allergy and Infectious Diseases, National Institutes of Health, Department of Health and Human Service, Herndon, VA 2000.
Van de Perre P, Jacobs D, Sprecher-Goldberger S. The latex condom, an efficient barrier against sexual transmission of AIDS-related viruses. AIDS 1987; 1:49.
Weller S, Davis K. Condom effectiveness in reducing heterosexual HIV transmission. Cochrane Database Syst Rev 2002; :CD003255.
Nicolosi A, Corrêa Leite ML, Musicco M, et al. The efficiency of male-to-female and female-to-male sexual transmission of the human immunodeficiency virus: a study of 730 stable couples. Italian Study Group on HIV Heterosexual Transmission. Epidemiology 1994; 5:570.
Comparison of female to male and male to female transmission of HIV in 563 stable couples. European Study Group on Heterosexual Transmission of HIV. BMJ 1992; 304:809.
Powers KA, Poole C, Pettifor AE, Cohen MS. Rethinking the heterosexual infectivity of HIV-1: a systematic review and meta-analysis. Lancet Infect Dis 2008; 8:553.