LIVER FLUKE DISEASE 227 



Indian and American allies all have histories very similar to that 

 of the oriental species. Their occurrence in man in countries 

 where fresh-water fish is a common article of diet, and their 

 frequency in animals which eat raw fish, strongly suggest fishes 

 as intermediate hosts. 



These liver flukes, like the sheep fluke, live chiefly in the gall 

 bladder and bile ducts where they often cause much mechanical 

 obstruction on account of their large numbers. Severe infections 

 such as occur in countries like Japan where raw fish is commonly 

 eaten cause symptoms of a very serious nature. One of the most 

 prominent of these is enlargement of the liver accompanied by 

 more or less bloody diarrhea; the latter becomes more and more 

 constant as time goes on. The liver sometimes becomes pain- 

 ful, and jaundice is a frequent symptom. The patient becomes 

 anemic, emaciated and weak, and is ready prey for other diseases. 

 There are often periods of partial recovery followed by relapses, 

 probably due to reinfections, and the patient ultimately becomes 

 exhausted and succumbs to a cold, an attack of malaria, or other 

 ailment from which one would ordinarily recover readily. 



There is no specific treatment for the disease. The only meas- 

 ures that can be taken are to remove the patient from any possible 

 source of reinfection and to keep him in the best possible general 

 health, with wholesome diet, good air and proper exercise. How 

 long the flukes persist in the liver is not known. 



Means of prevention of the disease are suggested by what is 

 known of the life history of the parasites. The most important 

 measure is unquestionably the suppression of the habit of eating 

 uncooked fish in places where the disease is endemic. Kobayashi 

 has shown that while the larvae of C. sinensis are killed at once on 

 exposure to a boiling temperature and in a short time when ex- 

 posed to considerably lower temperatures, they are not de- 

 stroyed by exposure to vinegar for five hours, nor by refrigeration. 



Much could also be done by destroying the snails which act as 

 the first intermediate hosts by means of copper sulphate, as sug- 

 gested on page 211. Another measure, which is far less reliable, 

 is the prevention of contamination of water in which fish live. It 

 is impossible to prevent some contamination of water by the lower 

 animals which carry the infection, and it is nearly as difficult to 

 prevent contamination by human fasces. The almost universal 

 use of night soil (human faeces) for fertilizer in oriental countries 



