224 



THE FLUKES 



access to the human body. The disease is said to have increased 

 in Peru, having been introduced there by Japanese and Chinese 

 laborers. If this is true some Peruvian animal, probably a 

 fresh-water crab, must serve as an intermediate host. This 



suggests that the disease if once intro- 

 duced might flourish in other countries, 

 especially where fresh-water crustaceans 

 are eaten. Lung fluke infection is 

 evidently another disease for which a 

 quarantine should be established. 



Liver Flukes 



Although the liver fluke of the sheep, 

 Fasciola hepatica, and other flukes of 

 herbivorous animals are occasionally 

 found in man, they cannot be looked 

 upon as usual human parasites. Adult 

 liver flukes are sometimes accidentally 

 eaten with raw liver, in which case 

 they attach themselves to the mem- 

 branes of the throat, causing irritation, 

 congestion, a buzzing in the ears, 

 difficult breathing, and other quite 

 alarming symptoms. Vomiting to ex- 



6X6- p.- 



pharynx; gen. p., genital pores; 

 V. s., ventral sucker; sh. gl., so- 

 called vittelline or yolk glands 



Fig. 74. The Chinese fluke, pgj ^jje worms Usually gives immediate 



Opisthcyrchis sinensis. X 02. 



m., mouth in oral sucker; ph., reliei. 



There are several species of flukes, 

 however, which are apparently espe- 

 reaiiy shell glands; ut., coiled ciaUy adapted for parasitizing carnivo- 



egg-nlled uterus; int., intestine; 1 



sp. d., sperm duct; ov., ovary; rous ammals, and which are common 

 sem. rec, seminal receptacle, human parasites in some countries. 



where sperms for fertilizing eggs ': . 



are temporarily stored ;t., testis; Japan, China, the Philippines and Other 

 exc. excretory canal; exc p oriental countries are especiaUy affhcted 



excretory pore. (After btiles.) '^ ■' 



by these flukes. The commonest species 

 in man is the Chinese fluke, Clonorchis sinensis (Fig. 74) which 

 is found in all of southern Asia from Ipdia to Korea. In some 

 parts of Japan about 60 per cent of the population are said to 

 harbor it in their livers, sometimes in hundreds or even thousands. 

 Leiper found it common in both dog and man in the vicinity 



