ABSTRACT
The human immunodeficiency virus (HIV) was recognized as a human pathogen just over 20 years ago but in that time it has infected millions of people, resulting in a global pandemic. The consequence of HIV infection is a relentless destruction of the immune system culminating in the diagnosis of acquired immune deficiency syndrome (AIDS). The World Health Organization estimated that at the end of 2005, 21.8 million people had died of HIV/AIDS and that 40.3 million people were living with HIV. In many established market economy countries, a significant reduction in the death rate for people with AIDS has been seen following the introduction of potent combination antiretroviral drugs. Thus in these countries there are increasing numbers of people living longer with their HIV.
