吡喹酮外用霜剂预防日本血吸虫尾蚴感染的研究

Study on praziquantel external cream in prevention of schistosome cercaria infection

目的观察吡喹酮外用霜剂预防血吸虫尾蚴感染的效果。方法用含吡喹酮的1％和2％外用防护霜剂，采用即时接触感染实验和水冲延迟接触感染实验两种方式对昆明小鼠进行预防血吸虫尾蚴感染的实验，同时用去氯水做对照。观察不同浓度、不同方式感染后小白鼠和对照组小白鼠的肝脏外观及镜下虫卵结果，同时对检获的血吸虫成虫数进行比较，实验组和对照组的成虫数采用方差分析进行比较，两种实验方式之间的成虫数采用t检验进行比较。结果两种剂型、两种实验方式的小鼠解剖后，肝脏均呈鲜红色，表面光滑，压片镜检均未发现虫卵，也未检获血吸虫成虫，而对照组小鼠肝脏均色暗，有不同程度的表面结节，压片镜检均发现了散在或成堆的血吸虫卵，同时检获了不同数量的血吸虫成虫，即时接触感染实验对照组检获的成虫数为（6．17±3．86）条，水冲延迟接触感染实验对照组检获的成虫数为（9．50±3．98）条。两种方式对照组与实验组检获血吸虫成虫数比较，其差异具有统计学意义（F=14．316，P〈0．01；F=20．990，P〈0．01），两种方式对照组检获血吸虫成虫数之间比较差异无统计学意义（t=-1．159，P〉0．05）。结论吡喹酮外用霜剂能较好地防御血吸虫尾蚴感染。

Objective To observe the effect of praziquantel external cream preventing skin invasion from Schistosoma cercariae. Methods Experimental mice were spread with 1% or 2% praziquantel external cream on the shaved abdomen skin respectively before infection, control group mice were treated with free-chloride water the same way. The instant contact and delay contact infection experiment with free-chloride water wash- ing methods were used to carry out the infection of schistosome cercaria . The appearance and Schistosoma eggs of the mice liver in both experimental and control group were observed under microscope. Meanwhile, the number of Schistosomajaponicum worms was compared. The number of adult worms between the experimental group and the control group was compared by analysis of variance, the number of adults between two kinds of experimental methods was compared using t test. Results The liver surface of experimental group mice was smooth. Eggs and worms were not found. However, the livers of control group mice were dark in color with nodules of different degree on surface, scattered or piles of schistosome eggs were found under microscopy, and various number of adult Schistosoma were collected. There were 6.17±3.86 and 9.50±3.98 adults found in the control group of instant contact infection experiment and delay contact infection experiment respectively. There was significant difference of adult Schistosoma number between experimental and control group at two different methods（F=14.316, P〈0.01 ; F=20.990, P〈0.01）.There was no significant difference of adult Schistosoma number between two control groups（t=-1.159, P〉0.05）. Conclusion Praziquantel external cream has efficiency on preventing Schistosoma cercariae from skin invading.