Hansen's disease (leprosy) in Japan, 1947-2020: an epidemiologic study during the declining phase to elimination.

OBJECTIVES: Leprosy, or Hansen's disease was a major public health problem in Japan in the early 20th century. Today, the number of new cases has decreased significantly. We aimed to investigate the trends of leprosy in Japan over the past 73 years and the challenges faced in recent years. METHODS: We assessed the data on newly registered cases of leprosy from 1947 to 2020. RESULTS: A total of 10,796 newly registered cases of leprosy were reported during the study period, of which 7573 were registered in mainland Japan, 2962 in Okinawa, and 250 were of foreign origin. Most autochthonous cases were born before 1950 in mainland Japan and before 1975 in Okinawa. The number of nonautochthonous cases surpassed that of autochthonous cases in 1992. Nonautochthonous cases originated from 26 countries, particularly Brazil and the Philippines. Three cases of antimicrobial resistance have been detected among nonautochthonous cases since 2004. CONCLUSION: Our data suggest that ongoing transmission of leprosy likely ceased in the 1940s in mainland Japan and in the 1970s in Okinawa. With the recent rise of nonautochthonous cases with globalization, continuous surveillance and efforts to maintain leprosy services within the country are necessary even after reaching the state of elimination.

[Survey of newly diagnosed leprosy patients in Japan (1993-2000)].

We analyzed the medical and social problems of newly registered leprosy patients in the past 8 years from 1993 to 2000 in a low endemic country, Japan. There were 56 registered Japanese patients (males, 32; females, 24), and 76 registered foreign patients (males, 56; females, 20). The number of Japanese patients in each year was between 5 and 9, and 2/3 of them were from Okinawa Prefecture, located in subtropical zone. But the number of foreign patients in each year was between 5 and 18, and 2/5 of them were from Brazil. The number of foreign patients was greater than that of Japanese patients. Male/female ratio has decreased among the Japanese.