482 OCCUUKENCB AND MEDICINAL SIGNIFICANCE. 



time from Tmnia, or that the disease sometimes assumes an epidemic 

 character. ^ 



If it be asked in what way the transmission of the worms takes 

 place, the general answer is, that it is effected by the eating of raw or 

 under- done beef. At least this is the rule, for we hardly need to con- 

 sider the cases in which infection may have been caused by the goat, or 

 the giraffe, or even by the sheep (for in spite of the above-mentioned 

 negative results, the latter is, perhaps, like the goat, capable of rearing 

 bladder-worms). 



The important share that the eating of raw flesh has in 

 determining the occurrence of the worm, has already been shown 

 by the large number of cooks and maid- servants infected with 

 tape-worm, regarding whom it may be added that if they would eat 

 the flesh in the same manner as their superiors, without tasting it 

 beforehand, they would probably hardly have to suffer in any greater 

 proportion. We must also notice the fact which, since Weisse's 

 day, has been often observed, that this parasite is very frequent in 

 persons, young or old, who from dietetic reasons have been fed on 

 raw beef.^ 



It is not, however, only in raw flesh that the bladder-worm is 

 transmitted to the future host, but also in meat in a half-cooked 

 condition, which appears not unfrequently upon our tables in the 

 form of roast beef and beef-steak a I'Anglaise. I know defi- 

 nitely, for instance, of one case, in which the Tmnia sagirMa origi- 

 nated from a beef-steak, which the host, a colleague now dead, 

 had eaten in Nice. Besides the dishes just mentioned, all those 

 should be deemed suspicious in which the flesh and blood are 

 almost or altogether of their original condition and colour. Only 

 well-cooked, thoroughly boiled or roasted, flesh sufficiently insures us 

 against infection. 



Eegarding the effect produced on the bladder-worm by the method- 

 ical application of a higher temperature, we have, thanks especially to 

 the investigations of Perroncito, a series of interesting conclusions.' 

 We learn for example that the motions of the worm, which at a low 

 temperature (up to about 30° C.) were very slight or altogether 

 absent, became extremely lively at 36-38°, but afterwards subsided, and 

 at 44° almost entirely ceased. At 45° C. death ensued, as was shown 



' For oases of this kind see Davaine, loc. cit., second edition, p. 100. I may also refer 

 to the observation of Knox already mentioned (p. 459). 



^ This is the case not merely in Germany, but also in France and Italy ; see for 

 example Levi, " Delia frequenza della taenia per Tuso medico della came di manzo cruda, 

 (liornale Vencto di sci. med., vol. i., p. 169, 1876. 



' " Delia grandine o panioatura," Torino, 1 877, and especially " Esperimenti sulla pro- 

 duzione della Tienia mediocg))f^(jl^^'(;j8^y'^)^|f^^g)^@ 



