HIV can be transmitted in several different ways, most often through:

• Unprotected anal or vaginal sex (the most common way people get HIV in the US,

• Sharing needles and/or works in intravenous drug use situations,

• Blood transfusions and accidents in health care settings, and

• Mother-to-child transmission during birth or through breast milk.

With the advent of mandatory blood bank testing and anti-HIV medications given to mothers with HIV, the last two methods of transmission have almost disappeared in the United States.

HIV can also enter the body through open cuts or sores or by directly infecting cells in the mucous membrane like the lining of the rectum or vagina. Transmission can also happen in the mouth and/or eyes, although this is insanely difficult. HIV cannot cross healthy, unbroken skin.

Sexually, most infections occur from unprotected anal or vaginal sex. With respect to anal sex, the bottom is at a higher risk of being infected than the top – but this does not mean that the top is not at risk. The mucous membranes on the head of the penis and in the piss slit (urethra) can absorb HIV, so the top is still at risk of contracting HIV during anal or vaginal sex.