While much has been done to educate the American public about how HIV is transmitted, many individuals are unaware of, or ignore facts about, the methods of transmission. Some people are in "high risk groups," but they are not the only ones who become infected with HIV.
HIV is transmitted through body fluids, e.g. blood, semen, and vaginal secretions. Most infections occur in the course of anal, vaginal, or oral sexual contact with an infected person. A baby can also acquire the disease from his or her infected mother perinatally, i.e., at some point around the time of birth, or later by drinking her breast milk, another body fluid that carries HIV. People may also be infected through blood transfusions or transplanted organs.
The connection between drug use and HIV arises because intravenous drug users share needles and
syringes that have not been sterilized. When these instruments are exposed to infected blood, the disease can pass from an HIV-positive person to another who is not infected. Substantial numbers of individuals are infected with HIV because of drug use. Later they can pass the virus on to others through sexual contacts or more instances of needle-sharing.
In this country the groups at greatest risk, according to the Centers for Disease Control and Prevention (CDC) in A Glance at the HIV Epidemic (http://www.cdc.gov/nchstp/od/news/At-a-Glance.pdf), are men who have sex with men, intravenous drug users, and people who have heterosexual contact with infected individuals.