Overview of HIV and AIDS: biology and epidemiology of the virus.

HIV-1 infects mononuclear cells using the CD4+ molecule and the chemical receptors of those cells. After a prolonged clinical latency period, the ability to replace destroyed cells is outpaced by ongoing cellular destruction, leading to the characteristic immunodeficiency of AIDS and its opportunistic infections and neoplasms. In the United States, the number of new cases of AIDS has diminished in recent years, although in some groups, such as women, the number of new cases continues to rise. In the developing world, AIDS remains a pandemic of huge proportions. In the absence of an effective vaccine, culturally appropriate efforts at education and behavior modification offer the best hope of controlling AIDS.