You can contract HIV by:

Having unprotected sexual intercourse with someone who is infected

Sharing needles or body piercing equipment with someone who is infected

Being given a transfusion of infected blood

Allowing infected fluids to get into a cut or sore anywhere on your body

Babies born to HIV positive women can be infected during pregnancy and birth, or through breast feeding

HIV is present in the saliva of an infected person, but not in quantities sufficient to transmit infection. Once infected fluids have dried, the risk of them transmitting the virus is considered to be close to zero.

The key methods of preventing the transmission of HIV are by not having sex with anyone who is, or may be, HIV positive, or by using latex condoms.

Latex condoms are essentially impermeable to HIV-sized particles. If used properly and consistently, they are considered highly effective in reducing the risk of transmission – although no protective method other than abstinence is 100% safe.

Injecting drug users can reduce the risk of contracting HIV by not sharing needles.