HIV can be transmitted through sex without a condom, sharing needles or syringes, contact with contaminated blood, and from mother to baby during pregnancy, childbirth, or breastfeeding. The virus may be present in blood, semen, vaginal fluids, pre-ejaculatory fluid, and breast milk.
Sexual transmission is most common during anal or vaginal sex without a condom. Oral sex carries a lower risk, but transmission may still occur if there are sores or injuries in the mouth. Sharing razors, nail clippers, toothbrushes, or medical instruments contaminated with blood may also increase the risk.
HIV is not spread by hugging, kissing, sharing dishes, using the same towels or bedding, insect bites, air, swimming pools, sweat, tears, or saliva. Blood and donated organs are tested before use, so transmission through transfusions or transplants is extremely rare.
Use condoms correctly during every sexual encounter and never share needles, syringes, or sharp personal items. After possible exposure, seek medical care promptly to discuss testing and post-exposure preventive treatment. Do not take HIV medicines without medical guidance.