CHAPTER XII 



DIPHTHERIA 



DIPHTHERIA is an infectious disease caused by the 

 Bacillus diphtherice, which was discovered by Klebs 

 in 1883 and first isolated by Loffler in 1884, hence the 

 name, Klebs-Loffler bacillus of diphtheria. 



An enormous amount of research has been applied 

 to the bacillus of diphtheria and its toxins, which led 

 to the discovery and use of an antitoxin serum for 

 the prevention and cure of diphtheria, that may be 

 considered one of the most important contributions 

 of bacteriology to medical science. 



Bacillus diphtherice is a slender rod varying in 

 length from 1 /x to 6 //-, presenting a beaded or gran- 

 ular appearance and sometimes showing clubbed 

 ends. No other known bacillus shows so great a 

 variety of shapes and sizes, nor in artificial media 

 produces so many involution (abnormal) forms. 



The diphtheria bacillus does not form spores and 

 has no power of motion. 



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