Surveillance of Brug's Filariasis in Post Prevention and Control Program Period in Sichuan

Objective To understand the epidemiological characteristics of Brug's filariasis and changes in vectors in post prevention and control program period,consolidate the achievement of filariasis control program and provide scientific evidence to prevent the re-emergency of filariasis.Methods The surveillance of etiology,serology and vectors of filariasis as well as chronic filariasis survey were conducted.Mass treatment with hetrazan salt and the remaining infectious source survey were carried out too.Results During the first six years after the basic control of filariasis in Dongpo district of Meishan county,7 remaining cases with microfilaria in blood were detected among risk population in surveillance sites,3 of which were re-found cases and 4 were newly-found cases.During the first 1 to 5 years after the basic control of filariasis in Junlian county,Yucheng district and Muchuan county,2,1 and 1 remaining cases with microfilaria in blood were detected respectively by cross-sectional surveillance,of which 1 once refused treatment,2 of 3 newly found cases were missed cases.After the elimination of filariasis in 4 counties,no microfilaria in blood was detected and no new chronic filariasis cases were found for 14 years.Conclusion At early stage when filariasis was basically control,the transmission still existed.However,after the implementation of further prevention and control measures,no microfilaria was detected.The surveillance indicated that the effect of consolidating measures was obvious.Now the attention should be paid on the chronic filariasis patients.