[Studies on the surveillance and purifying measures for filariasis in controlled areas].

This paper reports the results of longitudinal surveillance of filariasis for 4 years in Jining City, Shandong, where the disease has been controlled. It showed that the microfilaremia rate dropped from 0.48% to 0.03% and no new case was found and the natural infective rate of the main vector mosquito Culex pipiens fell from 0.45% to 0.03% and no larva III was detected. The purifying measures should put emphasis on the management of migrating persons repeatedly examining and treating old microfilaremia cases, the border areas with high microfilaremia rate, as well as working out a plan to cure the advanced patients and mosquito control measures with special reference to construction of new village settlements.