170 INFECTIONS OF THE DIGESTIVE TRACT 



apparently does not extend to completely reciprocal 

 pathogenicity, for mouse typhoid bacilli have never been 

 known with certainty to cause the typhoidal disease in 

 man, whereas the paratyphoid bacillus B is pathogenic 

 for mice. 1 Of greater importance is the fact that the 

 widely distributed bacilli of paratyphoid B are cer- 

 tainly the cause of many outbreaks of meat poisoning, 2 

 and that the bacilli of certain cases of meat poison- 

 ing are identical with some which cause typhoid fever. 

 A highly instructive instance is one lately reported in 

 detail, in which seven persons living hi one house suffered 

 from an infection by paratyphoid B bacillus. 



All the members of a family fell acutely ill with vomit- 

 ing, diarrhoea, and fever. At the end of three days the 

 temperature had returned to normal in all the patients 

 except one, and in this instance the illness ran the course 

 of a moderately severe typhoid, the fever lasting eighteen 

 days. The sera from all these patients gave positive 

 agglutinations with the bacillus of paratyphoid B. 



Why it is that some persons develop an acute gastro- 

 enteritis after infection with this bacillus while others 

 have typhoid fever, is still somewhat obscure. In cases 

 of meat poisioning, the infected meat contains not only 

 the bacilli but certainly also poisons derived from them. 

 The presence of these poisons accounts for the acute 



1 It is also possible that the use of the absorption methods which 

 reveal common agglutinins would show that the agglutinations 

 for these three organisms (now claimed to be identical) are not in 

 reality absolutely identical. 



2 Levy and Fornet, " Nahrungsmittelvergiftung und Paraty- 

 phus," Centralbl. /. Bakt., Orig., xli, p. 161, 1906. 



