Human immunodeficiency virus, or HIV, is transmitted through contact with specific bodily fluids, including semen, vaginal and rectal fluids, blood, and breast milk, according to AIDS.gov. Infection may occur during activities such as sexual intercourse, organ transplants, blood transfusions, breastfeeding and injection-based drug use.
Contrary to past beliefs, HIV is not transmitted through saliva, sweat or tears, and an infected person doesn't endanger others by shaking hands, AIDS.gov states. Infected fluids must be exposed to damaged tissue or areas of the body containing mucosal membranes, such as the rectal or vaginal lining, to spread the virus. Mothers can transmit the virus to infants during pregnancy or childbirth, and an injection from a contaminated needle or syringe may also transmit the virus directly into the bloodstream. Health-care workers are at risk of contracting the virus if they receive a puncture wound from an infected needle, but such cases are rare.
HIV may not trigger any health complications for years, but early symptoms may include fever, aching muscles, joint paint, enlarged glands, and chills or sweats, Medical News Today states. Sore throat, red rashes, weight loss and fatigue are also common symptoms. An untreated HIV infection puts individuals at high risk of developing acquired immune deficiency syndrome, or AIDs, a medical condition characterized by an abnormally weakened immune system.