The Okinawa Archipelago consits of 72 islands in which 48 islands have small population but most of them have been isolated and have few social communication and interchange between each other for a long time.
To investigate leprosy epidemiological status and to find out the epidemiological pattern to decide leprosy endemic situation, these islands are suitable fields for the study.
The data on Leprosy Annual Incidence Rate (I. R.), Lepromatous Annual Incidence (L. I. R.), Lepromatous Ratio (L. Ratio) and Child Ratio (C. Ratio) have been collected from ten islands since 1931.
Sometimes new leprosy cases were not considered as newly manifested patients in the year, because leprosy disease is chronic and usually it takes several years for the patients to be diagnosed as leprosy after they developed the disease. So the data are counted by 5-year period.
The follwing becomes clear after the leprosy epidemiological assessment on the data of islands given here;
1. Leprosy in the Island of Iheya, Ie, Aguni, Tonaki and Zamani are almost eradicated already.
2. Leprosy in the island of Irabu, Tarama and Kume are still endemic and forcast to get more new cases in future.
3. Leprosy in the Island of Yonaguni is still highly endemic.
According to the result of analysis of the data, the leprosy epidemiological patterns of gragh which indicate the epidemiological situation are shown below;
1. In the leprosy high endemic stage, the gragh of I. R. L. I. R. L. Ratio and C. Ratio show rising equally and locate in high level.
2. In the eradicated stage, all four graghs show falling down parallel with each other and locate in low level or reach 0, in this case C. Ratio surely precedes falling down or become 0 before the other three graphs show falling down.

抄録全体を表示

Recently the epidemiological improvement on leprosy disease in the Ryukyu Island has been observed. Leprosy Prevalence Rate (P. R.) and Leprosy Incidence Rate (I. R.) in the Island in 1970 were 1.97‰ and 0.088‰, but on the other hand the P. R. and the I. R. were 1.34‰ and 0.059‰ in 1975. So generally the leprosy epidemiological status in the Island has improved after the reversion of the Island to Japan in 1972. The drift of population to the urban areas from the rural areas has taken place from 1971, especially after the reversion. The rural areas (Miyako Islands, Yaeyama Islands and other Islands in Okinawa) have been sparsely populated and the urban araeas (Naha City, Urazoe City and their outskirts) have been rapidly grown in population.
According to the drift of population, the geographical status on leprosy endemic in the Island has something been changed after 1971. In regard to leprosy onset place, the following change can be observed: in the Naha City (one of the urban areas) the total number of newly-detected patients was only 5 (I. R. 0.017‰) in 1969 but in 1974 was 20 (I. R. 0.065‰). On the other hand in Miyako Islands (one of the rural areas) the number was 38 (I. R. 0.552‰) in 1969 and in 1974 was 17 (I. R. 0.293‰).
The another statistics shows as follows: The ratio of the annual newly detected patients in Naha City to total number all the Ryukyu Island was 5.2% in 1969 and 28.2% in 1974. But the ratio in Yaeyama Islands was 21.6% in 1969 and only 7% in 1974.
So before the reversion, the endemic pattern on leprosy disease was as follows: Leprosy infection and onset have occured in the same place in the rural areas. But after the reversion, the pattern was changed as follows: Leprosy infection has occured in the rural areas and the disease developed in the urban areas.
The phenomenon of the change on leprosy onset place in the Ryukyu Island after the reversion seems to be caused by the movement of population, by social developement in the rural areas and also by the improvement of leprosy endemic status in the Islands.
From the fact described above, it may be concluded that leprosy control programs in the urban areas in the Island should be more emphasized in the furture.

抄録全体を表示

A simple and rapid method for the collection of leprosy bacilli from infected tissues was studied to obtain the purified bacilli available to the metabolic investigations.
The results are summarized as follows:
Murine leprosy bacilli were collected from leprous spleen of mice by repeated centrifugations, followed by the treatment of crude bacillary fraction with water adjusted to pH 10.5 and shaking at 37°C for 60 min. The bacilli obtained by this method were found to be almost free from host tissue components by the test for the acid phosphatase and β-glucuronidase activities which are involved in lysosomes of host tissues, in addition to the microscopic and electron microscopic analyses.
The bacillary preparations thus obtained showed high activities of mycobacterial enzymes such as FAD dependent NADPH-cyt. c reductase and NADH-cyt. c reductase.
The human leprosy bacilli, collected from leproma of armadillo by this method, were also pure microscopically and enzymatically as above and showed to maintain the activity to incorporate label from L-methionine-14CH3S into bacterial lipids.
From these results, the influence of the alkaline treatments employed for the collection of bacilli from infected tissues on bacterial enzyme activities was discussed.

抄録全体を表示