Natural history of HIV/AIDS

AIDS was first recognized in 1981 and is caused by HIV-1. HIV-2 causes a similar illness to HIV-1 but is less aggressive and restricted mainly to West Africa. In 2007, the World Health Organization (WHO) estimated that there were 33.2 million people living with HIV/AIDS, with 2.5 million new cases (including 330,000 children) and 2.1 million deaths. Whilst the death toll remains high, in the last 3 years the number of drugs and classes of drug available for the treatment of AIDS has increased hugely. Our better understanding of the pathogenesis of the disease and the opportunistic conditions associated with HIV, together with the enlarged drug repertoire and alternative treatment strategies, is modifying the natural history of the disease.