猪囊尾蚴Cysticercus cellulosae

组员：杨滨 袁镜乐 杨童周 张迪

Introduction

Adult ： Taenia solium （猪带绦虫）

Taeniidae ( 带科 ) Taenia （带属）

Final hosts ： humans Intermediate hosts ： pigs,wild

pigs( 野猪 ) ， dogs,camels,cats etc.

Sites: skeletal muscles( 横纹肌 ) ， heart( 心 ) ， brain（脑）， eye （眼） etc.

Morphology

Cysticercus cellulosaeoval,as big as soy beansemitransparent cyst( 半透明包囊 )filled with liquidnodule( 小结 ):a scolex inside,4 suckers and many hooks on the scolex

MorphologyAdultlength ： 2~5m700-1000 proglottidsscolex:sphericity,25~50hooks,4suckersmature proglottid: without digestive system( 无消化系统 ),a reproductive system in each( 每个成节均有 1 套雌雄生殖器官 )gravid proglottid:full of eggs

Life cycle

A taperworm larval cyst is ingested by human through poorly cooked infected meat.

The larval escapes the cyst and passes to the small intestine( 小肠 )where it attaches to the mucosa by the scolex suckers.

Life cycle

The proglottids develop as the worm matures in 3~4 months.

The adult may live in the small intestine for as long as 25 years and pass gravid proglottids with the feces.

Eggs extruded from the proglottid contaminate and persist on vegetation for several days and are consumed by pigs in which they hatch and form cysticerci in muscle.

Life cycle

Epidemiology

Pigs can be infected by ingestion of eggs in feed contaminated with human feces

Human may become infected with cysticercus by eating raw or improperly cookd infected pork

No obvious seasonality,but rise in warm seasons

Sporadicity( 散发性 ) Susceptible animal:3~5 years in pigs

Signs

no obvious signs in a general way under serious infection malnutrition( 营养不良 ),growthretardation,anaemia

( 贫血 ),muscle edema( 水肿 ) “drunkenness( 醉酒状 )"

Lesions（病变） Pork is pale and moist

Cysticercus can be found in muscle as well as brains,eyes,livers,spleens,lungs and even in lymph bodes and fat

Cell infiltration then fibrosis and become calcification after death about half year

Diagnosis

Contour （外形） Eyelid （眼皮） Eye ground （眼底） Lingual root （舌根） Inner thighs （大腿里）

1.experience of the public

Diagnosis

cardiac muscle( 心肌 ) masseter( 咬肌 ) lingual muscle( 舌肌 ) limbs( 四肢 )

2.Sanitary inspection of the pork

A definite diagnosis can be made with finding cysticercus in those sites.

Diagnosis

Control Periodic inspection,

deworming : Praziquantel( 吡喹酮 ) ， Albendazole( 丙硫苯咪唑 ) ， Flubendazole( 氟苯咪唑 )

Positive census of cysticercus cellulosae patients Enhance excrement management Ban no inspection of pork listed Change your diet

References

李国清 . 兽医寄生虫学 ( 双语版 ). 北京 : 中国农业大学出版社 ,2006

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