Can kissing an HIV positive person cause an HIV infection?

No, HIV cannot spread through kissing.

HIV can be found in very small amounts in saliva. But there are proteins and enzymes in saliva which reduce how infectious the virus is. This makes it impossible for HIV to spread through kissing.

HIV does survive in other body fluids like blood, semen, vaginal fluid, anal mucous and breast milk. It spreads when these fluids are exchanged and shared.

The most common way that HIV spreads is through sex without a condom. This includes anal and oral sex too. HIV can also spread by sharing needles. It can also be passed from an HIV-positive pregnant woman to her unborn baby. This is rare as HIV tests are given during pregnancy and steps are taken to stop passing the infection on.

If you think you've been exposed to HIV in the last 3 days (72 hours), contact your local sexual health clinic to get post-exposure prophylaxis (PEP). PEP can stop the infection if you take it within 72 hours. 

If you think you've been exposed to HIV, but it was more than 3 days ago, wait for 7 weeks after the sex before taking a test. Before 7 weeks, the test won't be accurate. During this time you should not have sex or use a condom when you have sex.

Reviewed by Dr Paula Baraitser. Medical Director
Last updated at: 02 February 2024
Published on: 12 August 2022