Major changes are occurring in the epidemiology of opportunistic infections
(OI) in patients with acquired immune deficiency syndrome (AIDS) and treat
ed with highly active antiretroviral therapy (HAART). A marked decrease of
minor and major OI was observed and clinical resistance of thrush to antifu
ngal agents became extremely rare. Primary and secondary prophylaxis agains
t Pneumocystis carinii infections can be stopped; however, the situation is
less clear for other OI such as cryptococcosis or endemic mycoses. The epi
demiology is dramatically different in the countries which cannot afford th
e cost of HAART for the majority of patients, such as South Africa. These t
opics will be discussed in this paper.