Environmental adaptation of Echinococcus in South America

对乌拉圭细粒棘球绦虫的流行现状和环境适应性进行了研究。最重要的产业是畜牧业。一项问卷调查显示，约20%的居民进行了家庭屠宰羊。本文对639只羊的内脏进行了切片检查，发现有包虫囊存在。绵羊包虫病的患病率约为40%。被检羊包虫囊平均强度为1.67。大多数羊怀有几个囊肿。包虫病在睡眠中的患病率随年龄增长而增加。半数成年羊有包虫囊。囊肿数量每年平均增加约1。3岁以上的绵羊可育性囊肿发病，5岁以上的绵羊可育性囊肿发病率约为10%。5岁以上绵羊的平均受精囊数为4个。每一个可育包囊的平均原孢子数为1，437个。大多数可育囊肿含有少于500个原孢子。我们用槟榔碱调查了狗的患病率。细粒棘球绦虫在农场的流行率约为23%或更高。城镇犬的患病率低于农场犬。通过对77只流浪犬的尸检调查，发现3只犬感染细粒棘球绦虫，并对乌拉圭羊、牛细粒棘球绦虫COI基因进行了序列分析，以确定其遗传变异。结果表明，乌拉圭有普通绵羊感染细粒棘球蚴病，本研究建立了检测细粒棘球蚴病犬粪抗原的单克隆抗体夹心ELISA方法。用ELISA法检测了实验感染细粒棘球绦虫的犬粪抗原排泄的时间过程，发现细粒棘球绦虫绦虫在免疫抑制的沙鼠小肠内发育成绦虫期，但未能从这些动物体内回收到完全成熟的寄生虫。

Epidemiological status and environmental adaptation of Echinococcus granulosus in Uruguay were studied. Most important industry of Urugyay is livestock industry. A questionnaire survey shown that about 20% of the inhabitants carried out home-slaughtering of sheep. Dogs have access to the viscera of sheep in farms.Viscera of 639 sheep were sliced and examined for hydatid cysts. Prevalence of hydatid cysts in sheep was about 40%. and mean intensity of hydatid cysts in examined sheep was 1.67. Most sheep harbored few cysts. Prevalence of hydatid disease in sleep increased with age. Half of adult sheep had hydatid cyst. Average increase in number of cysts per year was about 1. More than 3 years old sheep harbored fertile cysts, Prevalence in more than 5 years old sheep was about 10%. Mean number of fertile cysts in more than 5 years old sheep was 4. The mean number of protoscoleces per fertile cyst is 1,437. Most of the fertile cysts contain less than 500 protoscoleces.We examined the prevalence in dogs by arecoline survey. Prevalence of E.granulosus in farms is about 23% or more. Prevalence in dogs in town is lower than that in farm. In a survey by necropsy of stray dogs in town, 3 of 77 dogs were infected.DNA sequence of COI of E.granulosus from sheep and cattle in Uruguay were analyzed for determinination of genetic variation. The results showed that common sheep strain distribute in Uruguay.We developed a sandwich ELISA using monoclonal antibody for detection of coproantigen in E.granulosus infected dogs. The time course of coproantigen excretion from dogs experimentally infected with E.granulosus was monitored by this ELISA.Tapeworm stage of E.granulosus developed in the small intestine of immunosuppressed jirds, but fully matured parasite were not recovered from these animals.