HIV prevention

How is HIV transmitted?

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If you are having sex, it’s important to know how HIV is transmitted. HIV is sexually transmitted through unprotected anal (penis in anus) or vaginal (penis in vagina) sex. There is also an extremely small chance of catching HIV during receptive oral sex (sucking a person’s penis).

Unprotected means sex without condoms or Pre Exposure Prophylaxis (PrEP). People with HIV who are on effective treatment cannot pass the virus to others (undetectable).

What increases the risk

The risk is higher to the person who is being penetrated in all cases. Things which increase the risk are the presence of semen or blood. Longer or more traumatic sex increases the risk, as do multiple sexual partners.

People with HIV are particularly infectious in the first few months after they catch the virus (and are often unaware that they have the infection).

Risk by type of sex

Highest risk

  • Condomless receptive anal sex (being penetrated anally)
  • Sharing injection equipment (needles etc)

High risk

  • Condomless insertive anal sex (your penis in their anus)
  • Condomless receptive vaginal sex (their penis in your vagina)

Low risk

  • Condomless insertive vaginal sex (your penis in their vagina)

Extremely low risk

  • Condomless receptive oral sex (sucking their penis)

No risk

Other types of sex are considered too low risk for HIV transmission. It is not transmitted through skin-to-skin contact, kissing, sharing household equipment or spaces (for example cutlery and toilets).

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