POSSIBLE MODES OF INFECTION. 531 



eaten raw, and all this has tended to restrict the frequency of the 

 tape-worm. Yov the calculation of the per-centage we can only rely 

 upon the reports of Miiller, according to which" Tmnia solium was 

 found nineteen times in 3814 post-mortem examinations (in Dresden 

 and Erlangen) — that is, about once in 200 examinations, or 0-5 per 

 cent. In Dresden its occurrence was somewhat more frequent than 

 in Erlangen. 



After what we have said on a former occasion regarding the trans- 

 ference of Tmnia saginata, it is easy to see that the occurrence of 

 T. solium is by no means exclusively determined by the consumption 

 of flesh, but quite as much, and indeed almost more, by the condition 

 and preparation of the meat. And the more frequently the latter is 

 eaten in a raw or half-raw condition, in consequence of local or 

 individual custom, the more does the danger of infection increase. 



It is true that, upon the whole, pork is much less frequently eaten 

 raw than beef, and that it is also less frequently ordered for dietetic 

 purposes ; but in certain districts, and especially where there is a large 

 manufacturing population, it is a favourite dish in the form of mince- 

 meat, which is merely salted and peppered. Speculative butchers 

 even prepare this mince-meat from measly flesh, which thus loses its 

 suspicious appearance, but almost none of its danger ; for, as we have 

 seen (p. 382), the bladder-worm heads are alone sufficient to transmit 

 the tape-worm. 



For the same reason, the prepared meats bought in small portions 

 in butchers' shops (and particularly sausages and ham) are by no 

 means so harmless as at first appears. They probably often form the 

 vehicle of Taenia solium, and all the more so, since butchers are accus- 

 tomed to remove the free-lying bladder-worms with the knife, and 

 perhaps with the very same one which is afterwards used to chop up 

 the meat. 



Further, when we consider the great adhesiveness possessed by the 



bladder- worms and their heads, on account of the damp nature of their 



surface, it will be seen that the possibility of a transference is by no 



means hmited to such a case. The possibility is always present 



wherever raw pork is stored, and the transmission may be effected by 



the most manifold objects, and that all the more easily since, as is 



well known, the bladder-worm of the pig is found very frequently, 



and usually in great numbers. Nor are the worms transferred in food 



only. Under some circumstances, even the hand is quite sufficient, 



especially since, to quote the common saying, there is but a short road 



from it to the mouth. Cases have even been heard of in which not 



only children, but even adults, have picked up and swallowed single 



bladder- worms in the kitclien. , , ,,. ^^ 

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