AIDS prevention in Japan and its cost benefit aspects

Abstract

Since the acquired immunodeficiency syndrome (AIDS) in Japan is in the initial stage of its spread (the first case was reported in 1985, and cumulative cases numbered 21 as of September 1986), we estimated the magnitude of the imminent epidemic using Delphi technique, and analyzed economic performance of preventive health programs. The annual incidence predicted for the years 1988, 1991 and 1996 was 100, 450 and 950, respectively (Japanese population 120 million, calculated cumulative incidence for the initial 5 years 0.4/100000 in Japan, 10.8/100000 in U.S.A.), implying that the AIDS epidemic in Japan would be roughly one-thirtieth of that in the U.S.A. during the initial period. This conservative prediction can be explained by the following factors: the populations of homosexual men and drug abusers are far smaller than those in the U.S.A.; low seroprevalence among homosexual men (4% or less in Japan vs 37–67% in U.S.A.); the absence of buildup in AIDS incidence in the initial period. Preventive programs involve: (i) surveillance and education for hemophiliacs and homosexual men including counselling clinics run with strict confidentiality; (ii) education of physicians and the public, especially travellers to ‘high risk countries’; and (iii) screening of donated blood samples. The outcome of cost-benefit analysis appears to depend on the scale of blood donor screening program. Preventive programs focused on the counselling and education of homosexual men are highly cost-effective. On the other hand, if the screening of all the blood donors in Tokyo and other metropolitan areas is undertaken, the program is bound to yield a net loss under the predicted epidemiologic circumstances.