The etiologic agent of filariasis in the Ryukyu Islands is Wuchereria bancrofti. It is nocturnally periodic and is transmitted by Culex fatigans. A program aimed at the control of filariasis began in January 1965. The island of Miyako was selected as the initial target, and over 97 percent of the population was examined and, if necessary, treated with diethylcarbamazine. Use of this drug over a one-year period successfully converted 82 percent of treated microfilaria carriers and produced an impressive decline in the average microfilaria density per 30 cmm of blood. The method of examination and treatment is discussed and data are presented on the results of therapy by municipality, age, and sex and the implications of these results are analyzed. The medical control of filariasis was complemented by extensive vector control measures. The relative failure of this aspect of the program is included in the discussion.
Captain, MC, U. S. Army, Chief, Medical Affairs Division, Department of Public Health and Welfare, United States Civil Administration of the Ryukyu Islands, APO San Francisco 96248.
Chief, Preventive Medicine Section, Department of Welfare, Government of the Ryukyu Islands, Naha, Okinawa.