492 MICKOBIOLOGY OF SPECIAL SIGNIFICANCE 



changes must begin at the surfaces of the pieces of meat and gradually 

 extend inward. In diseased animals, bacteria more frequently circulate 

 in the blood, and the flesh may be contaminated throughout when the 

 animal dies of the disease or when it is slaughtered, not only with the 

 specific germs of the disease but also with bacteria derived from the 

 intestinal tract of the animal. It is a matter of observation that 

 the flesh of diseased animals is more liable to undergo early putrefac- 

 tive and poisonous changes than that derived from healthy animals. 

 Hashed meat is, of course, much more prone to bacterial decomposition, 

 because in it the bacteria have become well distributed throughout 

 the mass, and ideal conditions are provided for the development of 

 anaerobic as well as aerobic bacteria. Minced chicken and chicken 

 pie appear to be very frequent sources of acute poisoning in the United 

 States, and epidemics of sausage poisoning have repeatedly occurred, 

 especially in Germany. The bacteria found to be concerned in these 

 instances have been B. enteritidis, B. paratyphosus, B. coli, and B. 

 botulinus. Some of these poisons, as for example the toxin of B. 

 hohilinus, are rendered inert by boiling, but occasionally bacterial 

 poisons which are not destroyed by such high temperatures may be 

 present in food. Moreover, meat rendered poisonous by these bacteria 

 may show no evideace of putrefaction. B. {Proteus) vulgaris has 

 also been found in some samples of poisonous meat, and this finding is 

 usually associated with definite evidence of putrefaction. 



The symptoms of meat poisoning are usually those of acute gastro- 

 enteritis, vomiting, cramps, and diarrhoea. The patients often recover 

 very quickly, but occasionally the illness is rapidly fatal, or it may 

 merge into a subacute form resembhng or identical with paratyphoid 

 fever. In those instances of poisoning due to the presence of B. 

 botulinus the symptoms are of a different kind, consisting almost 

 solely of nervous disturbances, secretory and motor paralyses, without 

 fever, resembling in many respects poisoning with atropin. In this 

 form of meat poisoning the death rate is relatively high, about 40 per 

 cent of the cases ending fatally. 



Fish poisoning is of two general kinds, that due to poisons natural 

 to the fish, and that due to poisons formed by bacterial activity in the 

 flesh of the fish. Blanchard has applied the Spanish-name " Siguatera " 

 to the first kind and the term "BotuHsm" to the second. In the 

 Japanese fish of the genus Tetrodon the roe is poisonous, giving rise 



