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PUBLIC HEALTH BACTERIOLOGY 



ferment dextrose but not maltose. A vaccine treatment 

 for gonococcus has been used with success in chronic cases. 

 An emulsion of gonococci in sterile salt solution (0-85 per 

 cent) is heated to 65 C. for i hour. Inject 300 million, 

 and give dose every 7 to 10 days, increasing to 1000 to 

 1 200 million. 



MICROCOCCUS TETRAGENUS. 



Found in 1881 by Gaffky, in pulmonary cavities. 

 Usually non-pathogenic in man. Grows weh 1 on ordinary 

 media, clouds broth evenly, does not liquefy gelatin, clots 

 milk with acid formation, is Gram-positive, and is cap- 

 sulated in the body. It is pathogenic to white mice, 

 causing septicaemia ; slightly so to guinea-pigs and rabbits, 

 and non-pathogenic to house mice and rats. It has been 

 described as the cause of abscesses, on one occasion of 

 meningitis, and on another of septicaemia. 



MICROCOCCUS CATARRHALIS. 



Found in patients suffering from catarrh of the upper 

 respiratory tract. Its chief claim to attention is its 

 similarity in staining and morphology to the meningo- 

 coccus and gonococcus. From the latter it is distinguished 

 by its rapid growth on the ordinary culture media. From 

 the meningococcus, with which it may be found in the 

 nasal passages, it is similarly distinguished, but here the 

 difference is one of degree only. The sugar tests are very 

 helpful. 



MICROCOCCUS MELITENSIS. 



This organism was first described by Bruce in 1887, 

 as present in the spleen of patients dead of Malta (or 

 undulant, rock, Mediterranean, or Neapolitan) fever. 



