PREVENTIVE MEDICINE 337 



Infection is transmitted to the pig through ingesting the eggs 

 of T. so Hum excreted in human faeces. It is not as yet clear how 

 the larval forms reach their resting places. 



" Measly " pork is unfit for food, as a high temperature is 

 required to destroy the parasite which might therefore escape 

 destruction under ordinary conditions of cooking. The ingestion 

 by man of undercooked " measly " pork gives rise to T. solium in 

 the intestines, and in this way the cycle is completed. 



PREVENTIVE MEASURES. These should be directed toward the 

 hygienic disposal of human faeces. Pigs rooting in woods, under- 

 growth, or behind hedges and in similar places would become in- 

 fected if people who defaecate in such places harbour the adult 

 tapeworm. Protection is afforded to people by the proper 

 inspection of meat and the efficient cooking of pork sausages. 

 Greater opportunities are offered for contamination of the land 

 with t&ni<B in country districts than in towns owing to the more 

 indiscriminate disposal of human faeces and to the more cursory 

 inspection of meat. 



C. bovis. This is the larval form of T. saginata which is some- 

 times found in the intestines of man. The cysts are located chiefly 

 in the masseter muscles; more rarely in other parts. Cases are 

 seldom met with in this country, though fairly common in Germany 

 and other parts of Europe. 



PREVENTIVE MEASURES. These are the same as for C. 

 celluloses, and especial care should be taken that the drinking 

 water of bovine animals is not contaminated with human faecal 

 matter. 



C. tenuicollis. This larval form of T. marginata is found 

 chiefly in the peritoneal cavity and liver of the ox, sheep and pig. 

 The adult worm is parasitic in the dog. 



PREVENTIVE MEASURES. Prevention is secured on the one 

 hand by burying or otherwise effectually destroying all dead sheep 

 or other animals, and on the other hand by administering vermi- 

 fuges to farm dogs and destroying their excreta. 



C. pisiformis. These cysts are found in the peritoneal cavity 

 and liver of rabbits and hares, being the larval forms of T. serrata 

 which inhabits the intestine of the dog. 



C. fasciolaris. Is found in the liver of rats and mice, the adult 

 form being the C. crassicollis of the cat. Fillers* found it in 10 

 per cent, of rats examined in stables where cats were kept. 



Prevention can be effected, as before indicated, by destroying 

 the carcases of the cyst carriers and by the administration of vermi- 

 * System. Vet. Med., Wallis-Hoare, 1915, Vol. II., p. 1489. 



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