ECHINOCOCCUS DISEASE 529 



quence of Posselt's very interesting investigations, I incline more and more 

 to the view that there are two forms of tenia echinocoecus. 



I should like here to refer to the fact that bone echinococci, which in their 

 distribution show great similarity to the multilocular echinocoecus, are fre- 

 quently identified with these. In bone echinocoecus we are dealing with the 

 exogenous proliferation of small and very small cysts deposited close beside 

 each other; but, besides these, there are also larger cysts with encapsulated 

 daughter-cysts in the surrounding soft parts. Now such larger cysts with 

 daughter-cyst formation are a characteristic of the hydatid form in which it 

 differs markedly from the multilocular form. For this reason it cannot be- 

 assumed that every osseous echinocoecus belongs to the multilocular form. 



Besides being found in man, the echinocoecus has been noted particularly 

 in the lung and the liver of sheep, in cattle, and in pigs ; more rarely in the 

 dog, the cat, the mule, the horse, the zebra, the dromedary, the camel, the 

 giraffe, etc. 



Since it has been demonstrated with certainty that the echinocoecus cysti- 

 cercus occurring in man and his domestic animals represents one and the same 

 tape-worm, there can no longer be any question as to the propagation of echino- 

 coecus disease in animal and man — that the dog takes up the grown cysticerci 

 which develop in the domestic animals. The possible modes of dissemination 

 of echinocoecus disease in any country will therefore depend upon the number 

 of its domestic animals, and the distribution of the echinocoecus pest among 

 them. As a matter of fact, those countries, such as Iceland, Victoria, Mecklen- 

 burg and New Pomerania, in which the echinocoecus occurs most frequently, 

 are noted for an excessively large number of animals, particularly cattle. A 

 number of years ago I endeavored to investigate the distribution of this para- 

 sitic disease, and from the reports of 52 slaughter-houses I decided that the 

 echinocoecus occurs, upon the average, in 10.79 per cent, of cattle, in 9.83 per 

 cent, of sheep, and in 6.47 per cent, of pigs. Pomerania and Mecklenburg in 

 Germany are first in the frequency of the echinocoecus disease. In Greifswald 

 the dissemination of the pest is enormous. In one period of six months 68.58 

 per cent, of cattle, 51.02 per cent, of sheep, and 4.93 per cent, of pigs were 

 found diseased. The conditions are similar in Mecklenburg. From my pre- 

 vious investigations I have concluded that the prevalence of the echinocoecus 

 infection in the inhabitants of a country is in proportion to the distribution of 

 the echinocoecus pest among its domestic animals. 



In man, as well as in domestic animals, the dog is the usual, if not the 

 only, transmitter of the infectious germ. The greater the number of dogs 

 in any infected country, the greater the danger of contagion. In my own 

 vicinity, the number of dogs, particularly in the rural districts, is very great. 

 Apart from hunting dogs and shepherd dogs, almost every family possesses 

 a house dog. He accompanies his master as he works about the farm, espe- 

 cially when milking cows, which in the summer occurs twice during the day, 

 hence he has repeated opportunities to visit the grazing cattle, and to deposit 

 his feces upon the field. Here, on the small grazing places, the focus of mfec- 

 tion must be sought for the grazing eattje, which remain here for months, by 

 day and by night. 

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