[Future prediction of tuberculosis incidence rates by prefecture].

We tried to predict the tuberculosis incidence rates by the year 2000 and 2005, based on the trends of incidence rates from the year 1981 to 1995 reported by the Ministry of Health and Welfare (MOHW). According to the studies conducted, the tuberculosis incidence rate in 2000 was predicted as 29.8 (95% CI: 28.7-30.8) per 100,000 population and that in 2005 was predicted as 25.2 (95% CI: 24.2-26.3 per 100,000 population in Japan. The incidence rates by prefecture in 2000 and 2005 were also predicted. The MOHW introduced some new tuberculosis control plans and has set on interim goal by the year 2000 to achieve a tuberculosis incidence at below 20 per 100,000 population. Whereas the possibility of achieving the stated incidence rate goal even by the year 2005 is very low in Japan, among prefectures, several prefectures were predicted to reach this level by the year 2000. Over several years the incidence rate in Japan has been high in the west and low in the east. However this is expected to greatly change in the future. The speed of decline in tuberculosis incidence rates has been stagnated since around 1980 with average annual declination rate from the year 1981 to 1995 was 3.3%. Among 17 prefectures, Tokyo Metropolitan had the lowest declination rate with an average annual declination rate of 1.1%. The prefecture surrounding Tokyo also showed low declination speed. This may indicate that in the future, the problems of tuberculosis will be concentrated in and around the big cities.