ABSTRACT
The acquired immunodeficiency syndrome (AIDS) was first noticed in the United States of America in 1981, when the U.S. Centers for Disease Control and Prevention (CDC) reported the unexplained occurrence of Pneumocystis carinii pneumonia and Kaposi’s sarcoma in previously healthy homosexual men [1-3]. Soon thereafter the disease became recognized in male and female intravenous drug users as well as in recipients of blood transfusions and in hemophiliacs. As the epidemiological pattern unfolded, it became clear that an infectious agent transmissible by sexual contact and blood and from mothers to infants
was the cause of the epidemic. In 1983 a retrovirus, later designated human immunodeficiency virus (HIV), was isolated from a patient with lymphadenopathy [4], and by 1984 HIV was demonstrated to be the most likely causative agent of AIDS [2,4]. Identification of the causative agent allowed the development of diagnostic assays and provided the basis for a scientific approach to specific therapy. Epidemiological studies revealed a global pandemic [5,6], and its staggering worldwide growth was matched by an unprecedented explosion of information on all aspects of HIV disease. Despite tremendous efforts and significant progress in many areas of HIV research, two decades after its discovery the worldwide spread of the virus continues at an alarming pace.
