552 THE ANIMAL PARASITES OF MAN 



These were actually produced by the parasite, for after its destruction by in- 

 jections into the nose of corrosive sublimate solution and the internal admin- 

 istration of antipyrin, these nervous symptoms at once disappeared. 



The diagnosis where oxyuriasis is suspected depends upon investigation of 

 the feces, or examination of the anus and its surroundings. If the iinding 

 is negative, the patient is told to use a small enema of cold water immediately 

 upon the appearance of the symptoms. In the return flow of the water, the 

 parasites, if present, will be readily recognized. The microscopic examination 

 of the soiled parts around the anus readily reveals eggs if present. Ova are 

 found in the feces only if simultaneously also the macroscopically recognizable 

 female oxyuris is present. 



The removal of oxyuriasis often requires great patience. In the first 

 place it is necessary to prevent the importation of ova by all tendencies and 

 habits which favor this. The sleeping together of well and sick children, the 

 common use of clothing, sponges, towels is to be prohibited. Frequent 

 change of bedding and cleanliness of the finger nails, etc., are to be advised. 

 Moreover, the parasites which are present in the small intestine, and particularly 

 in the cecum, must be expelled by purgatives, such as castor oil, rhubarb, com- 

 pound infusion of senna, etc. At the same time I employ santonin. But the 

 simultaneous employment of intestinal infusions is absolutely necessary in 

 order to expel the oxyuris which have entered the large intestine. In severe 

 cases I add to the water one to two teaspoonfuls of chlorin water, vinegar,- 

 0.2 to 1 per cent, of medicated soap. As a common household remedy garlic 

 is also employed. 



Among the most frequent and also, as a rule, most harmless intestinal para- 

 sites is the 



Trichocephalus dispar, BudolpM, 1801. 



This organism is well known, and therefore a zoologic description is un- 

 necessary. 



The parasite does not require an intermediary host. We have little knowl- 

 edge of the method by which it enters the human intestinal tract. Its long 

 period of development and the great resistance of the ova to external influ- 

 ences evidently favor the invasion. Dried and pulverized to dust, they are 

 readily consumed with raw fruit, vegetables or drinking-water, and thus enter 

 the human organism. After the young embryos have left the membrane of the 

 ovum, they attain their development in the small intestine, and finally lodge 

 in the cecum. The parasite is usually found in but few specimens. If found 

 numerously the signs of chronic catarrh may develop in that part of the intes- 

 tinal tract which they inhabit. The parasite adheres to the mucous mem- 

 brane in such a way that the anterior end of the head, which is curled in sev- 

 eral folds, surrounds the individual parts of the mucous membrane. In other 

 cases it has been proven that the entire anterior thin portion of the body — more 

 than two-thirds of the worm — penetrates the surface of the intestinal mucous 

 membrane. Accordingly it is often very difficult to loosen the parasite from 

 its hold in the mucous membrane. 



In regard to the symptoms, in general little is known. In many cases, 



