CHAPTER VII 



PATHOGENIC ORGANISMS 



Streptococci. Although the etiological relation of septic 

 sore throat to infected milk has been noted on many occasions 

 in Great Britain during the past thirty years, it is only during 

 the past decade that any systematic investigations have been 

 carried out and the bacteriology of this pathological condition 

 developed. Probably the first bacteriological examination of 

 any note was made in connection with the Angelsey outbreak 

 of 1897 ^ when it was reported that Staphylococcus pyogenes 

 and Streptococcus pyogenes were found in the milk but no B. 

 diphtheria. Examination of the patients' throats gave similar 

 results. Some of the most important contributions to the 

 bacteriology of septic sore throat are those of Savage.^ Of the 

 36 cases of mastitis investigated, 21, or 68 per cent were due to 

 streptococci, 5, or 16 per cent to staphylococci, and the re- 

 mainder to B. coli, B. tuberculosis and unclassified causes. 

 On cultivation of the streptococci in the usual Gordon test 

 media, it was found that a large percentage was of one type, 

 called by Savage, Streptococcus mastiditis. This type tended 

 to long chain formation and grew luxuriantly in broth forming a 

 flocculent deposit above which the supernatant liquid remained 

 clear. Lactose, dextrose, and saccharose were invariably fer- 

 mented with the production of acid, and occasionally salacin, 

 raffinose, and inulin. Mannite was never fermented. In milk 

 acid was produced and a clot formed within three days ; gelatin 

 was not liquefied and no neutral red reaction was produced. 

 It was non-pathogenic to mice. In 16 cases of sore throat 

 Savage found the two chief varieties of streptococci to corre- 

 spond to Andrewes and Holder's Str. anginosus and Str. pyo- 



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