Evaluation of mass treatment of malayan filariasis by diethylcarbamazine in Cheju Island

, Seo, Byong Seol; , Whang, Koo Il

doi:1974.12.1.21

Korean J Parasito > Volume 12(1):1974 > Article

Original Article


Korean J Parasitol. 1974 Jun;12(1):21-32. English. Published online Mar 20, 1994. http://dx.doi.org/10.3347/kjp.1974.12.1.21
Copyright © 1974 by The Korean Society for Parasitology


Evaluation of mass treatment of malayan filariasis by diethylcarbamazine in Cheju Island
Byong-Seol Seo and Koo-Il Whang
Department of Parasitology and Institute of Endemic Diseases, College of Medicine, Seoul National University, Korea.


Abstract
Control programme of malayan filariasis by diethylcarbamazine was set up in village, Cheju-Island, Korea. The daily dose of 6 mg per kg of body weight for 6 days was chosen as a chemotherapeutic course only for microfilaria positives, which was repeated with an interval of one or two months. For the evaluation of drug control programme the yearly posttreatment blood survey was carried out. The results collected from 1970 to 1973 were analysed from the various points of view, such as microfilaria positive rates, incidence as well as prevalence rates. The change of microfilaria counts was also utilized for the comparison of the intensity of infection among population in the four year blood surveys. Considering the extremely skewed distribution of average microfilaria density, the mode of frequency distribution of microfilaria density in a population was particularly taken into account for the evaluation of changing endemicity affected by diethyecarbamazine treatment. The equation; Y= a+b log X(a , b: constants, X=microfilaria density; Y=probit scale of cumulative frequency of positives to X microfilariae) was found to fit farily well the data collected from four-year surveys before and after treatment. From these data obtained, four regression lines have been drawn by determining "a" and "b"; two paramenters, which were increased year by year since inauguration of control programme. In the present investigation, it was verified that the chmotherapeutic control measure of malayan filariasis applied in a village of Cheju-Island has been successfully carried out and the quantitative level of endemicity inthis area has also been distinctly lowered within the four-year control programme.

Figures


	Fig. 1 Case Distribution in Wimi-l-Ri (1970).


	Fig. 2 Histogram showing percentage of mf. positives by age and sex (1970).


	Fig. 3 Fluctuation showing the positive rates of mf. infection by age.


	Fig. 4 Fluctuation showing the average mf. count per positive by age.


	Fig. 5 Fluctuation showing the total mf. count by age.


	Fig. 6 Regression line of cumulative percentage of microfilaria positive cases against microfilaria density in log-probit scale (Che ju Island, Wimi-l-Ri, 1970 Survey).


	Fig. 7 Regression lines showing cumulative percentages of mf. positive cases by mf. density for four years project area, Wimi-l-Ri, Che ju Do.


	Fig. 8 Changing values of "a" and "b" of the regression equations, Y=a+b logX, by the successive four year surveys (1970-1973).

Tables


	Table 1 Results of the first year blood survey(1970)


	Table 2 Analysis based on the results of the successive two-year surveys (Population at 1970: 1,781, 1971: 1,835, 1972: 1,869, 1973: 1,878)


	Table 3 Results of the successive three-year survey (1972)


	Table 4 Summarized data throughout the four-year blood surveys (1970-1973)


	Table 5 Frequency distribution and cumulative percentages of microfilaria positive cases (1970-1973)

References


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