1. 后睾吸虫病 Opisthorchosis Speaker： Debbie Zhong 谭永锋 200830330522
谭永锋
张 冰
钟思昕

2. Opisthorchosis
The pathogen of Opisthorchosis is Opisthorchis felineus (猫后睾吸虫）and O.viverrini(麝猫后睾吸虫)of Opisthorchiidae（后睾科）.
parasitizing in bile duct of the liver of human and pigs, dogs and cats
Wild animal
This disease cause greater harm to Cats and Dogs
zoonotic trematodes,le

3. 1.病原形态 Morphology (1)Parasites
Opisthorchosis sp. is morphologically simillar to the Clonorchis sinensis（形态上与华枝睾吸虫相似）. Length 8-12 mm, width 2-3 mm. Flat leaf-shaped, narrow, slightly pointed front end.
Oral sucker is slightly larger than ventral sucker which is located in front 1 / 5 of the body.
Two large dendritic （分支状）testes locate in tandem（串联）in the back of the worm. Lobulated（分叶状）ovary lies before the testis, between the one large spermathecae（受精囊）and front testis.
Oral sucker
Ventral sucker
Uterus
ovary
spermathecae
testis

4. Clonorchis sinensis egg
（2）Eggs
Tiny
27-35×12-20μm
Tawny黄褐色
Bulb-like
Miracidium(in egg)
内含毛蚴
Operculum (above)
上端有卵盖
Protuberance(behind)
下端有一小突起

5. Life Cycle

6. Opisthorchis sp. parasitizes in the bile
duct of cats or dogs, then lay eggs
into bile, and let out
through digestive tract.
后睾吸虫寄生于犬猫胆管，并在
其内排卵，经胆汁流入小肠再随
消化道排出

7. The eggs will be eaten by the first
intermediate host, Bithynia leachii,
then turn into miracidium（毛蚴）.
miracidium
A month later they grow into
sporocyst (胞蚴) with redia（雷蚴）,
then turn into cercaria（尾蚴）
in another month and flee away,
swim in the water.
Cercaria

8. When they meet the second inter-
mediate host, fish, they squeeze in
the body of their host and grow into
metacercaria(囊蚴) in subcutaneous
fat or muscle. The metacercaria become mature in 6 weeks.

9. When eaten by cats or dogs, the larva( 幼虫) enter
liver through bile duct. Then turn into adult(成虫).

10. Epidemiology
The definitive hosts of Opisthorchis is Dog/Cat/ Fox, Marten貂, Lutra水獭
/Lion/ Pig and even Human.
Their eggs can survive in water for a long time. When in a 19°C condition, they can survive for at least 70 days. The infection rate can be 100% in cats and 90% in dogs in specific areas.

11. Symtom Mild infection : No obvious clinical symptoms
Severe infection: Systemic jaundice 全身性黄疸
depression 抑郁, loss of appetite 食欲不振; sometimes vomiting 呕吐, constipation 便秘 or diarrhea 腹泻, graduate emaciation消瘦 and obvious ascites 腹水.

12. Diagnosis
In vivo examination 活体检查: Sedimentation method 水洗沉淀法and Zinc Sulfate flotation method 硫酸锌漂浮法.
Postmortem examination : Parasites 虫体can be found in bile dust at liver by dissection解剖

13. Lesions
It can be seen dendritic
（分支状） from ERCP
(内镜逆行胰胆管造影 )

14. Treatment & Prevention
1.Praziquantel 吡喹酮 ：Preferred, mg/kg, days interval after the first oral taking.第一次服用后间隔5-7日再服第二次
2.Albendazole丙硫咪唑:25-50 mg/kg, Oral, Once per day, Keep taking for 2-3 days
Prevention: Dogs and cats should be fed with thoroughly cooked fish or frozen fish.