AIDS and HIV

Approximately 21 years ago, HIV, the virus that causes AIDS, was first identified. Today, the World Health Organization estimates that there are 42 million people living with HIV/AIDS worldwide; 38.6 million of these are adults, 19.2 million are women, and 3.2 million are children under the age of 15. In 2002 alone, 5 million new HIV infections occurred, and 3.1 million people died of HIV/AIDS-related causes. HIV/AIDS is now the leading killer among all infectious diseases, and is ranked fourth among all microbial causes of death. From its identification to the end of year 2002, about 27 million people died from AIDS. It is now the seventh leading cause of death among 1- to 4-year-olds, sixth among 15- to 24-year-olds, and second among 25- to 44-year-olds[Page 18] in the United States. About 95% of HIV infections are concentrated in developing countries. The first reported cases of AIDS in the United States were identified in 1981.

HIV causes AIDS. Over time, HIV depletes the subset of lymphocytes called T4 helper cells, or CD4+ cells, that are essential in the proliferation of cells necessary for cell-mediated immunity and the production of antibodies that protect us from infections. Without the ability for the body to produce these cells, we are vulnerable to a variety of infections caused by organisms and viruses that normally do not cause disease in individuals. It is these infections that create the symptoms and progression of illnesses that eventually kill patients who have AIDS. The Centers for Disease Control and Prevention (CDC) defines AIDS broadly as the onset of life-threatening illness that occurs as a result of HIV disease that originates with the infection of a person with HIV. Early in the epidemic, AIDS was thought of as the end stage of the disease process. However, since persons who receive an AIDS diagnosis who receive specialized treatments may recover from these AIDS-defining illnesses, receiving the diagnosis of AIDS is no longer necessarily associated with imminent death.