Cysticercosis bovis 牛囊尾蚴病 08 动医 2 班 梁正鹏 吴德鑫 钟露 管光梓 马邦帅

Introduction Cysticercus bovis is a larval parasite of Taenia saginata in human body. Cattle and buffalo are the most important intermediate host ， and human is only final host of Taenia saginata Goeze. It parasites on organs like lungs, liver,brain and all over the muscle tissue, creating mechanical damage even nervous signs.mechanical damage

Morphology( 病原形态 ) Adult parasitizes on human’s small intestine, is ivory and 4-8 meter- long. The mature Cysticercus bovis is ovoid, size like soybean and have a ivory cyst, about(7~10)mm×(4~6)mm,filled with liquid,

The front end of worm is smaller and gradually become wider and more flat. Scolex is about square, mm in diameter, have no rostellum and hooks, the top is recessed inside. There are 4 suckers like the cup in a scolex, 0.7~0.8mm in diameter, The neck is long and thin.

The worm have segments, each segment has both a set of male and female genital organ. Gravid segments account for one-tenth of total segments, there are a large number of eggs, which are round,tan,36 ～ 42μm in diameter.

Life Cycle （生活史） The eggs and gravid segment are discharged with stool. The eggs show a greater resistance to external environment, they can survive 168 days at -4 ℃,and can survive about 10 days in stool.externalenvironment When the intermediate host like cattle eats the polluted feed, developing from egg to Cysticercus bovis after days of infection.

When humans eat these Cysticercus bovis, they grow to adult after 3 months. Adult have long life as years in human body.

Epidemiology( 流行病学 ) Bovine cysticercosis have obvious regional characteristics, some local people like to eat raw beef. In severe endemic area, the prevalence of bovine cysticercosis are quite serious. Taenia saginata eggs are of strong resistance on the outside environment, survival for 22d in the hay meadow. People are only final host of Taenia saginata.

Symptoms( 症状 ) In general, cattle infected with cysticercus do not show clinical symptoms. Human infection with Taenia saginata, can cause digestive dysfunction, can lead to anemia and vitamin deficiency if long existence.

Diagnosis （诊断） 1 、 Combining with clinical symptoms, suspected cases are examined positive by IHA 、 ELISA.clinical 2 、 CT or MRI will help to clinical diagnosis for cerebral cysticercosis.clinicaldiagnosis 3 、 When pathogen in the subcutaneous nodules biopsy or brain operated pathological tissue was proved, it will be the basis of definitive diagnosis.biopsydiagnosis

Treatment and Prevention （防治） 1. Treatment Praziquantel( 吡喹酮 ) Mebendazole( 甲苯咪唑 ) 2. Comprehensive Prevention (1) Health education (2) Feces management( 粪便处理 ) (3) Periodic deworming( 定期驱虫 )