DIPHTHERIA BACILLUS I2Q 



some manner, the diphtheria bacillus then gains entrance and 

 the disease develops. The bacilli may be found in healthy 

 individuals who may act as a source of infection to sus- 

 ceptible individuals without themselves becoming infected. 

 They are seldom found in blood or other tissues; the symp- 

 toms arise mainly from the absorption of the toxin. 



Prevalence of Bacillus Diphtheria. Examinations made on 

 a large scale of the throats of supposedly healthy individuals 

 have shown that the Bacillus diphtherias is rather widely dis- 

 tributed. Not only does it linger for many weeks in the 

 throats of persons recently recovered from the disease, but it 



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;. 55. Bacillus diphtherias, from a pure culture. 



is found in the caretakers, nurses, etc., and there are allied 

 organisms, with more or less pathogenicity, that have been 

 found in atrophic rhinitis, in conjunctivitis, and in the throats 

 of unexposed normal individuals. 



Pseudodiphtheria. The pseudobacillus of Hoffman is be- 

 lieved by some investigators to be but a weakened diphtheria 

 bacillus that has lost its toxic power, but its true relation is 

 not settled. It is morphologically identical and at times is 

 found side by side with the true bacillus. It grows well 

 on agar, shows no granules with Neisser stain, and, contrary 

 to B. diphtheria, does not produce as much acid in dextrose 

 broth. 



