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Can HIV be transmitted through oral sex (fellatio and cunnilingus)?

Yes, but the risk is relatively low.

HIV is transmitted through seminal and vaginal fluids, including menstrual fluids. The virus can enter the body through the bloodstream or by passing through delicate mucous membranes, such as inside the vagina, rectum or urethra.

If a person is having oral sex and has bleeding gums, a cut, or an ulcer inside their mouth, HIV could enter their bloodstream through infected fluid. In the same way, a person with HIV could give HIV to their partner during oral sex, through that person's vagina, rectum or urethra.

Using a condom during sex, including oral and anal sex, is the best way to prevent sexually transmitted infections (STIs), including HIV. Avoid using an oil-based lubricant, such as Vaseline or baby oil, because they can weaken the condom and increase the risk of it splitting.

You can use a dental dam to cover the anus or female genitals during oral sex. A dental dam is a latex or polyurethane (very thin, soft plastic) square, measuring about 15cm by 15cm. It acts as a barrier to help stop STIs passing from one person to another.

HIV is transmitted through the exchange of bodily fluids, such as:

  • seminal fluid
  • vaginal fluids, including menstrual fluids
  • breast milk
  • blood
  • the mucous found in the rectum
  • pre-cum (the fluid that the penis produces for lubrication before ejaculation)

You can't catch HIV from:

  • kissing
  • being sneezed on by someone with HIV
  • sharing baths, towels or cutlery with an HIV-infected person
  • swimming in a pool or sitting on a toilet seat that someone with HIV has used
  • animals or insects such as mosquitoes

Other bodily fluids, such as saliva, sweat or urine don't contain enough of the virus to infect another person.

Read the answers to more questions about sexual health.