Epidemiological evaluation on the efficacy of the slowly released bar of parziquantel for dog use in the prevention of cystic echinococcosis in human and sheep
Abstract：To evaluate the efficacy of the slowly released bar SRP type of parziquantel in large scale for the prevention of cystic echinococcosis in human and sheep,this slowly released bars type SRP Ⅲ were planted subcutaneously in over 90% of dogs as the sole measure to control cystic echinococcosis in villages of agiricultural and pastoral areas in northern Xinjiang province with continuous observations for 4 years.The parameters for evaluation include infection rate of Echinococcus granulosus in dogs;positive rate of specific antibodies in pupils of 7 years old;prevalence of cystic echinococcosis in pupils of 2-16 years old and prevalence of echinococcosis of lambs within one year old.The results showed that the infection rate of E.granolosus in dogs before experiment was 41.22%,there were in 2 nd and 3 rd years after planting and was 2.98% at the end of 4 th year;The antibody positive rate in pupies of 7 years old was 41.23% before experiment.but this rate was gradually decreased after planting with this bar type SRP Ⅲ,and dropped to 5.36% at the end of 4 th year,while it was 30.6% in the control group for the same year.The prevalence rate of hydatid diseases in pupils aged 7-16 years old were 1.69% and 1.89% respectively in two villages before experiment,but there was no new patients could be found 3 years after experiment.The prevalence rate of echinococcosis in lambs within one year old was 44.77% before experiment,but it dropped to 10.66% 3 years after experiment,while it was 46.38% in the control group.It concludes that the period of efficient effect of planting with the slowly released bar with praziquantel may sustain as long as for three years after planting in dogs,and the application of this technique as a sole prophylactic measure may control the spread of cystic echinococcosis in human and livestocks.
