The medical condition known as AIDS—the acronym for Acquired Immunodeficiency Syndrome—has been called the modern equivalent of the plague. In the United States, the dreaded condition has had its greatest impact on gay men and on intravenous drug users (those who shoot drugs into their veins with a hypodermic needle). AIDS suppresses the individual's immune system, leaving them open to an array of diseases. First identified in 1981, the disease spread quickly. By 1996, AIDS was the eighth leading cause of death in the United States. By 2001, there had been 793,026 cases reported, according to the Centers for Disease Control (CDC). In Africa, where AIDS is primarily spread by heterosexuals, AIDS has decimated the populations of several poor countries and is a leading cause of death. Although the death rate from AIDS-related diseases in the United States has shrunken considerably thanks to prevention and breakthroughs in treatment, AIDS remains...