Global estimates of HIV infections and AIDS cases

Abstract

AIDS cases are officially reported to the World Health Organization (WHO) Global Program on AIDS (GPA) in Geneva, Switzerland, from member states via WHO's regional offices. This paper presents regional estimates of HIV/AIDS. Estimates of the annual number of AIDS cases which may have occurred were derived from the use of an AIDS estimation and short-term projection model developed by WHO. Estimates of HIV seroprevalence are based upon then available HIV serological data. For developed countries, HIV estimates developed by national experts and/or national AIDS programs were used, while estimates by regional experts were used for Latin America and the Caribbean. An extensive HIV information database, comprised of data from approximately 1000 published and unpublished reports of HIV serological surveys and studies, was used to estimate the HIV prevalence in African countries. For Asian and Pacific countries, an HIV database compiled by WHO was used. As of the end of 1991, 446,681 cases of AIDS had been reported to WHO/GPA. WHO, however, estimates 1,475,000 cumulative adult AIDS cases for the same period. The cumulative number of reported and estimated adult AIDS cases are reported, respectively, as follows: 129,066 actual and 970,000 estimated cases for Africa; 208,089 and 260,000 for North America; 44,888 and 145,000 for Latin America; 60,195 and 85,000 for Europe; 1254 and 10,000 for Asia; and 3189 and 5000 for Oceania. The highest estimated prevalence of HIV infections is in sub-Saharan Africa where more than 6 million adults may have been infected. Approximately one million HIV infections are estimated to have occurred in North America, more than one million in Latin America and the Caribbean, 500,000 in Western Europe, and more than one million in South and Southeast Asia. Most other areas are believed to have relatively low levels of HIV infection as of the end of 1991. The estimated male-to-female proportion of infected adults is almost equal or rapidly becoming so in Africa, Asia, and Latin America, while an higher male-to-female proportion continues to exist in North America and Western Europe, although the proportion of new HIV infections is slowly approaching one-to-one as heterosexual transmission increases in regional countries. In North America and Western Europe, the annual incidence of HIV infections is believed to have peaked during the first half of the 1980s. The annual incidence of HIV infection in the US since the mid-1980s is estimated to be 50,000. Annual incidence is believed to be increasing in sub-Saharan Africa, Latin America and the Caribbean. In Asia, extensive HIV transmission has been documented in only a few countries in South and Southeast Asia, such as India and Thailand, starting in the late 1980s. Infection has spread rapidly since then.