CHAPTER XVII. 

 MALTA OR MEDITERRANEAN FEVER. 



MICROCOCCUS MEWTENSIS (BRUCE); BACILLUS MEUTENSIS 



(BABES). 



General Characteristics. A non-motile, non-flagellate, non-spo- 

 rogenous, non-chromogenic, 'non-liquefying, pathogenic coccus, staining 

 by the ordinary methods, but not by Gram's method; characterized 

 by remarkably slow growth and by pathogenic action upon monkeys. 



In 1877, while working in Malta, Bruce* succeeded in 

 finding in every fatal case of Malta fever a micrococcus 

 which could be isolated in pure cultures from the spleen, 

 liver, and kidney, which grew readily on artificial media, and 

 which, when injected into monkeys, produced the disease. 



Morphology. Micrococcus melitensis, as Bruce called it, 

 is a round or slightly oval organism measuring about 0.3 ^ 

 in diameter. It is usually single, sometimes in pairs, but 

 never in chains. When viewed in the hanging drop it is 

 said to exhibit active "molecular" movements, but is not 

 motile and has no flagella. Babes f declares it to be a bacillus. 



Staining. It stains well with aqueous solutions of the 

 anilin dyes, but not by Gram's method. 



Thermal Death Point. This has been fixed by Dalton 

 and Eyre J at 57.5 C. 



Cultivation. The best medium for its cultivation is 

 said to be ordinary agar-agar. After inoculating, by a punc- 

 ture, from the spleen of a fatal case of Malta fever, the tubes 

 should be kept at 37 C. The growth first appears after 

 several days, in the form of minute pearly white spots scat- 

 tered around the point of puncture and along the needle 

 path. After some weeks the colonies grow larger and join 

 to form a rosette-like aggregation, while the needle tract be- 

 comes a solid rod of yellowish-brown color. After a lapse of 

 months the growth still remains restricted to the same area 

 and its color deepens to buff. 



* ''Practitioner," xxxiv, p. 161. 



t Kolle and Wassermann "Die Pathogenic Mikroorganisms," m, p. 

 443- 



t "Jour, of Hygiene," iv., 1904, p. 157. 



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