日本血吸虫经胎盘传播的实验研究

EXPERIMENTAL STUDIES ON CONGENITAL TRANSMIASSION OF SCHISTOSOMA JAPONICUM

目的 实验观察日本血吸虫的胎盘传播。方法 以家兔为动物模型 ,对母兔怀孕中期 (器官发生期 )和晚期 (胎儿发育期 ) ,人工感染不同量的日本血吸虫尾蚴 ,观察仔兔日本血吸虫感染情况 ,同时对仔兔断奶后进行攻击性感染。结果 母兔怀孕中期和晚期人工感染 30 0条尾蚴 ,母兔经胎传播率分别为 75 .0 %和 10 0 .0 % ,仔兔经胎感染率分别为 13.5 %和 46 .7%。母兔怀孕晚期分别人工感染 30 0、5 0 0、70 0条尾蚴 ,母兔经胎传播率均为 10 0 .0 % ,仔兔感染率分别为 46 .7%、6 1.9%、79.0 %。仔兔感染强度分别为 1- 3、1- 3条及 2 - 14条血吸虫。新产仔兔断奶后攻击性感染 2 0条尾蚴 ,实验组和对照组仔兔虫体回收差异无显著性 (P>0 .0 5 )。结论 仔兔日本血吸虫经胎盘感染率和感染强度与母兔怀孕不同时期 ,胚胎发育不同程度 ,尾蚴感染剂量等众多因素有关 ;仔兔经胎感染后 。

Objective To observe the congenital transmission of Schistosoma japonicum experimentally. Methods Mother rabbits in different pregnancy were infected with different doses of S.japonicum cercariae. A challenge infection was done for prenatal infected rabbitlets. Results In middle and later pregnancy, 13 5 % and 46 7 % of kittens were infected, respectively. The rabbits in later pregnancy were infected with 300? 500 or 700 cercariae, respectively. The infection rates of kittens were 46 7%, 61 9% and 79 0%, respectively. There was no significant difference between experimental and control groups of prenatal infected rabbits with 20 cercariae of challenge infection. Conclusion The congenital transmission of S. japonicum infection in rabbits happens. The infection rate of rabbit kittens might be related to different pregnancy of mother rabbits, embryo development, infection dose of cercariae, etc. The challenge infection suggested that the prenatal infected rabbitlets had no protective immunity.