400 PATHOGENIC BACTERIA. 



from a recent autopsy are not pathogenic in moderate 

 amounts for rabbits or guinea-pigs. Liver-tissue pre- 

 served at 28 F. in an antiseptic wrapper is very patho- 

 genic for guinea-pigs when injected subcutaneously, but 

 Sternberg found that this pathogenesis was not true of 

 yellow fever livers only, as it developed also in control- 

 autopsies. 



Extended research of the alimentary canal in yellow 

 fever showed the intestine to contain a great number of 

 bacteria, but no pure or nearly pure culture of any single 

 species, as in cholera. Few liquefying bacteria were 

 found, and the most abundant bacterium was, as in 

 health, the Bacterium coli communis. 



The most important micro-organism met with was 

 Bacillus x (Sternberg), which was isolated by the culture- 

 method from a considerable number of cases, and may 

 have been present in all. It was not present in any of 

 the control-experiments. It was very pathogenic for rab- 

 bits when injected into the abdominal cavity. Sternberg 

 says: u It is possible that this bacillus is concerned in the 

 etiology of yellow fever, but no satisfactory evidence that 

 this is the case has been obtained by experiments upon 

 the lower animals, and it has not been found in such 

 numbers as to warrant the inference that it is the veri- 

 table infectious agent." 



The latest researches upon yellow fever are those of 

 Sanarelli. 1 In studying the cadavers of yellow fever San- 

 arelli found them either entirely sterile or universally 

 invaded by certain microbic species, such as the Strepto- 

 coccus pyogenes, the colon bacillus, the protei, etc., 

 which cannot be the cause of the disease. In the second 

 case he examined he was fortunate enough to find what 

 he is satisfied is the specific microbe, the Bacillus ictcr- 

 oides. In ii autopsies he never found the organism 

 alone, but always associated with the ordinary bacteria 

 mentioned above. The Bacillus icteroides must be sought 

 for in the blood and tissues, and not in the gastro-intes- 



1 Brit. MeiL Journ., July 3, 1897. 



