This reports the results of epidemiological surveys on newly registered leprosy patients in Japan from 1964 to 1980 by late Dr. Seigo Hazama. He began the study on the new leprosy patients in the mainland in 1964 and added the cases in Okinawa Prefecture from 1974. The number of the new cases in the mainland; 606 between 1964 and 1973, 143 between 1974 and 1980. The new cases in Okinawa between 1974 and 1980 were 327. We analyzed these on the incidence, ratio of man and female, age distribution, their hometowns, family history, types of leprosy, the first clinical signs and disabilities on diagnosis. The new cases from 1981 to 1992 were 116 in the mainland and 214 in Okinawa by the studies of Ozaki and Tomoda; these results were cited on several points of the items above mentioned.

  With the decrease of new patients, a male preponderance had changed to nearly equal occurrence in both sexes. The decrease had progressed from the younger groups and the age distribution had peaked in the older age groups. Foreign leprosy patients had continuously been registered and they were mainly immigrants from Southeast Asians and South America. As for the types of leprosy, there was a bimodal distribution in L/LL and T/TT but cases of Borderline types had increased. The pattern of the distribution was different from Mainland to Okinawa.

  This study revealed such medical issues in leprosy in the second half of the 20^th century of Japan as early diagnosis, classification, disabilities on registration, accuracy of clinical records etc.