Introduction

The first cases of acquired immune deficiency syndrome (AIDS) were reported in the U.S. in June of 1981. The occurrence of the syndrome among gay men, intravenous (IV) drug abusers &, later, blood transfusion recipients & persons with hemophilia suggested a transmissible agent as the cause. In 1984, scientists identified a retrovirus, human immune deficiency virus (HIV), often known as human T-Iymphotropic virus type III/lymphoadenopathy, associated virus (HTLV-III/LAV), as the primary cause of AIDS. In 1985, screening tests to detect antibodies to HIV were licensed, allowing identification of infected individuals & the screening of the blood supply. Researchers have been able to map the genetic structure of HIV & to demonstrate the nature of the immune defect. Ongoing research is aimed at identifying risk factors & preventive strategies, evaluating antiviral drugs, developing drugs to increase the immune method, & developing a vaccine.