Acquired Immunodeficiency Syndrome

Since 1982 when the acquired immunodeficiency syndrome (AIDS) was first reported, at least 215,144 diagnosed cases of AIDS are presently known, with 120,069 cases reported from the North American continent and with 29,725, 40,519, 511, and 1,596 cases respectively from Europe, Africa, Asia and Australia. Countrywise, the United States tops the list with 117,781 reported cases, followed by Brazil, France, Uganda, Kenya, Tanzania, Italy, and Zaire with 9,555, 8,025, 7,375, 6,004, 5,627, 5,307, and 4,636 cases, respectively (WHO Wkly. Epidemiol. Rep. 2.02, 1990). AIDS is now known to occur worldwide (Brunet and Ancelle, 1985); the agent responsible has been isolated and determined to be a human retrovirus. The antigenic and molecular characteristics of the virus are indicative of its uniqueness among the human and animal retroviruses (Wong-Staal and Gallo, 1985). Its transmission is exclusively by sexual contact, prenatal transmission, or inoculation of infected blood/blood products, rather than casual contact (Friedland and Klein, 1987).