It is now 20 years since the first cases of acquired immune deficiency syndrome (AIDS) were discovered in sub-Saharan Africa. At the beginning of the third decade of the global pandemic, AIDS has reversed gains in life expectancy and improvements in child mortality in many countries; mortality among the population aged 15–49 has increased manyfold, even in countries with modest epidemics.1 AIDS is the leading cause of mortality among adults (WHO, 2004). According to estimates by the Joint United Nations Programme on AIDS (UNAIDS), as of the end of 2003, over 20 million people had died of AIDS. Some 38 million people are estimated to be living with the human immunodeficiency virus (HIV), the virus that causes AIDS, the overwhelming majority of whom—over 90 percent—are in the developing world.
Any discussion of the impact of acquired immune deficiency syndrome (AIDS) on health care systems must distinguish between treatment of the opportunistic illnesses associated with AIDS and treatment directed at the underlying cause, namely, the human immunodeficiency virus (HIV). Treatment of opportunistic illnesses can alleviate suffering but typically extends life by only months. Treatment that controls the HIV in the patient’s body, called antiretroviral therapy or ART, can be much more successful, adding years to life expectancy.