HIV transmission

HIV is present in the blood, breastmilk, and the semen, vaginal fluids or anal mucus of infected people, and can only be passed on to another person if these fluids get into his or her body. Although HIV has been found in the saliva of some people with HIV using very sensitive laboratory equipment, it is in such small quantities that it is not infectious.

The main ways HIV is transmitted are:

• By anal or vaginal sex without a condom. HIV cannot pass through good-quality condoms, and the failure rate of properly used condoms is extremely low.

• Through blood-to-blood contact. This mainly happens through sharing infected drug injecting equipment. In the past, before screening was introduced, some people were infected with blood and blood products during medical treatment. Very rarely, healthcare workers have been infected after accidentally pricking themselves with a needle contaminated with HIV-infected blood.

• From a mother to her baby. This is also called vertical transmission, and can happen during pregnancy, birth or breastfeeding.

Detailed information on HIV transmission can be found in the sections on Sex  and on  Mother-to-baby transmission of HIV .