292 TRICHINA WORMS 



occur unknown to the patient or to the observers who made 

 the records. 



The larval worms, which, as pointed out by Ransom, on account 

 of their advanced stage of development are comparable with 

 the nymphs rather than the larvse of arthropods, when encysted 

 in the flesh of some susceptible animal never develop further 

 until eaten by another susceptible animal. If they are eaten the 

 cyst is dissolved off in the intestine of the new host, the larvae 

 are set free in the digestive tract, and within three days be- 

 come sexually mature and copulate, to begin the performance 

 all over. 



Obviously man usually if not always becomes infected from 

 eating infected pork, whereas hogs may be infected not only 

 by eating scraps of raw pork but also by eating the bodies of 

 infected rats and mice. The latter animals are infected in 

 a similar manner. The number of trichina worms which may be 

 harbored by a single host is almost incredible. According to 

 the writer's investigations, the sausage which was the cause of a 

 recent epidemic in Portland, Oregon, contained over 2,000,000 

 larvae to the pound at a very conservative estimate, and in a bit 

 of human muscle from the diaphragm of an ItaUan who fell 

 victim to the disease the number of worms was even greater. 



The Disease. — The disease caused by trichina worms is more 

 fatal to man than to any other animal, the fatality sometimes 

 rising to 30 per cent or more of the cases. Even in man the 

 worms, if eaten only in small numbers, produce no serious or 

 even noticeable effect. When eaten in great numbers, however, 

 as would always happen in eating heavily-infected raw or under- 

 done pork, the worms produce symptoms so much like typhoid 

 fever that the disease is undoubtedly often diagnosed as such. 

 The course of the disease, as described by Ransom, is somewhat 

 as follows : the first symptoms of the disease — diarrhea, ab- 

 dominal pains and intestinal catarrh — are the result of irritation 

 of the. intestine by the adult worms, especially the females, which 

 burrow deep to deposit their young. Except in very light cases, 

 a sort of general torpor is noticeable, accompanied by weakness, 

 muscular twitching, etc. A very striking symptom, which ap- 

 pears in about a week and lasts for a few days, is a marked puffi- 

 ness or edema of the face and especially of the eyelids. As 

 pointed out by Ransom, the gravity of the case cannot be judged 



