Semen and vaginal fluid

HIV is found in semen and vaginal fluid and can be passed on through vaginal, anal and oral sex. The virus can also be present in the fluid that is released from the penis to help lubricate it during sex.

Reducing the risk

Anal and vaginal sex are the most common ways for HIV to be passed from an infected person to someone who doesn't have HIV. If you are going to have penetrative sex (which is when a man's penis enters someone else's body) then the most effective way of minimising the risk of HIV being passed from one person to another is to use a condom properly. A water based lubricant (never an oil based one) will reduce the risk of the condom tearing and make sex more comfortable.

Because the HIV virus is found in the fluid released before ejaculation, it is also important that the penis is covered with a condom before penetration and that this doesn't come off during sex. Relying on someone to withdraw their penis before ejaculation is not an effective way of preventing HIV infection.

There have been cases where someone has become infected through oral sex with an HIV positive man, where infected fluids from their penis get into the uninfected person's mouth. To reduce this relatively small risk you can use condoms for oral sex: some people prefer to use flavoured condoms for this.