Trends of tuberculosis rates before and after the declaration as a public health emergency in Japan, 1992–2006
SETTING: Over the period 1992 to 2006, Japan had tuberculosis (TB) notification rates of about 40 to 20 per 100 000 population. In 1999, the Minister of Health and Welfare of Japan declared a public health emergency based on the resurgence of TB.OBJECTIVE: To compare the trends of TB notification rates before and after the declaration.DESIGN: This is an ecological study on the trends of TB notification rates. The trends per year in TB notification rates were compared before (1992–1997) and after (2001–2006) the emergency declaration.RESULTS: The trends in the notification rates for all types of TB and sputum smear-positive TB (SSP-TB) decreased from −3.3% (95% confidence interval [CI] −4.6 to −1.9) and 0.94% (95%CI −0.33 to 2.2), respectively, per year before the declaration to −5.8% (95%CI −6.3 to −5.3) and −3.3% (95%CI −2.4 to −4.2), respectively, per year after the declaration with statistical significance. Trends in notification rates for both all types of TB and SSP-TB statistically significantly decreased after the declaration in Fukuoka, Osaka and Saitama Prefectures.CONCLUSION: The declaration of TB as a public health emergency in Japan in 1999 had a positive impact on TB control in Japan and thus TB epidemiology.