Kaposi's sarcoma as a sexually transmissible infection: an analysis of Australian AIDS surveillance data. The National HIV Surveillance Committee

Abstract

Objective: To further examine the hypothesis that Kaposi's sarcoma (KS) among people with AIDS is caused by a sexually transmissible infectious agent.

Design: Analysis of Australian AIDS surveillance data for the period 1982-1991 by sex, age, exposure category, country of birth, year and place of diagnosis.

Main outcome measures: Percentage of people with AIDS who had KS.

Results: In Australia, by November 1991, 17.2% (527 out of 3067) of individuals with AIDS aged > or = 13 years had presented with KS as their AIDS-defining illness: men, 17.6% (524 out of 2977); women, 3.4% (three out of 87) (P < 0.001). KS was predominantly reported in people aged 20-49 years and there were no cases in children < 13 years of age. In general, KS was more common in those who had acquired HIV by sexual contact rather than parenterally. Among people aged > or = 13 years, the proportion with KS ranged from 0.0% (none out of 41) in men with haemophilia to 1 Iford 9.0% (483 out of 2542) in men reporting homosexual contact. Between 1984-1985 and 1990-1991, the percentage of men with AIDS reporting homosexual contact who presented with KS declined from 30% (37 out of 124) to 15% (145 out of 995) (chi 2 for a linear trend, P < 0.001). For men with AIDS reporting homosexual contact, the percentage with KS in New South Wales and Victoria (20.3%) was higher than in the other States and Territories (12.5%) (P < 0.001). New South Wales and Victoria have also reported the highest incidence of AIDS in Australia.

Conclusion: The epidemiological characteristics of KS among people with AIDS in Australia are broadly consistent with those reported from the United States and Europe. This provides further evidence that KS may be caused by a sexually transmissible infectious agent. The nature of the infectious agent and its mode of transmission have yet to be determined.