DISEASES OF SWINE 539 



Symptoms of Trichinosis. The severity of the symptoms of 

 trichinosis depends upon the number of living larval worms taken 

 into the body. Three periods in the course of the disease are com- 

 monly distinguished. The first period begins in from two days to a 

 week, sometimes not for nearly two weeks after infestation. The 

 symptoms appearing in this stage are those of gastro-intestinal irri- 

 tation, due to the development of the worms in the intestine and 

 the liberation of the embryos, and consist of lack of appetite, nausea, 

 abdominal pains, diarrhea, and fever. These symptoms are not 

 constant, and are often absent. 



The symptoms of the second period that corresponding to the 

 migration of the embryos develop between the seventh and tenth 

 days, sometimes later. There is more or less fever, and the muscles 

 become tense and swollen and are painful on movement or pressure. 

 There may be pain and difficulty in chewing, swallowing, and 

 breathing on account of the involvement of the muscles concerned 

 in these functions. 



In the third stage, following the encystment of the worms in 

 the muscles, the patient becomes emaciated and anemic, watery 

 swellings appear, especially in the face, the skin may itch and 

 tingle, and eruptions sometimes appear. The duration of the symp- 

 toms as well as their intensity depends upon the degree of infesta- 

 tion. Trichinosis is often mistaken for typhoid fever on account of 

 the similarity of the symptoms, and the muscular pains are some- 

 times taken for rheumatism. 



In light cases recovery occurs in about two weeks; in severe at- 

 tacks it does not begin for six weeks, and several months may elapse 

 before the patient entirely recovers. In fatal cases death rarely oc- 

 curs earlier than the second week or later than the seventh, usually 

 between the fourth and sixth weeks, when the muscular symptoms 

 are at their height. 



The symptoms of trichinosis in hogs are similar to those in the 

 human patient, ordinarily much less pronounced, and recovery usu- 

 ally follows. During the migrations of the worms into the muscles 

 the animal moves with difficulty, the limbs are stiff, and the hind 

 quarters sometimes seem to be paralyzed. There is soreness of the 

 muscles, more or less diarrhea, and sometimes skin eruptions, so 

 that hog cholera may be suspected by the layman. As a rule, how- 

 ever, the symptoms are so slight that the disease in hogs passes en- 

 tirely unnoticed. 



Treatment of Trichinosis. If the disease is recognized early, 

 the patient may be treated with purgatives and vermifuges to expel 

 the worms from the intestines. There is no treatment which will 

 affect the embryos after their migrations are begun. 



Frequency of Trichinosis. The frequency of the disease in 

 man depends upon the frequency of infection in hogs used for food, 

 and upon the extent to which insufficiently cooked or raw, imper- 

 fectly cured pork is eaten. Nearly a thousand cases have been placed 

 on record or are definitely known to have occurred in this country, 

 and a large percentage 01 those patients whose nationality has been 



