HIV can be passed from one person to another through sexual contact, and in a number of other ways. Both men and women can have HIV, and can transmit the virus. You don’t need to have lots of sexual partners to become HIV positive.
HIV can be transmitted through heterosexual (straight) or homosexual (gay, lesbian) sex. In women who only ever have sex with women the risk of HIV being passed on is very low.
Most people with HIV will look and feel healthy, so you cannot tell who has the virus and you can transmit HIV without knowing you are HIV positive. If someone is taking anti-HIV drugs they can pass on HIV but the risk of this happening is significantly reduced.
HIV is transmitted from one person to another when the blood, semen, pre-ejaculate (precum), vaginal and anal fluids or breast milk of an infected person enters the body of an uninfected person by:
having unprotected (without a condom) vaginal or anal sex
sharing sex toys
using a needle or imjecting equipment which has already been used by someone who is infected with HIV.
A woman with HIV can transmit the virus to her baby before or during birth, or by breastfeeding. This risk can be reduced by testing and treatment during pregnancy, planing the delivery and avoiding breastfeeding.
The risk of HIV transmission as a result of unprotected oral sex is low but it can happen. You are more at risk if:
you are performing oral sex
your throat or mouth is inflamed or you have cuts, sores, abrasions or any unhealed piercing in your mouth
your partner ejaculates in your mouth
you have just brushed or flossed your teeth
you are giving oral sex to a woman who is having her period.
You cannot become HIV positive from hugging, saliva, kissing, sneezes, coughs, sharing baths or towels, from swimming pools, toilet seats or from sharing cups, plates or cutlery.
You cannot get HIV from any animals or insects, including mosquitoes. HIV is not passed on through biting.