Pathogenesis 651 



of diagnosis. This has been studied by Wright,* Birt and 

 Lamb,t and later by Bassett-Smith.J 



All of the observers have shown that the agglutinative 

 reaction takes place both with living and dead cultures of 

 the Micrococcus melitensis, but that to make the diagnosis 

 dilutions of serum equal to about i : 30, never greater than 

 i : 50, must be used. Birt and Lamb also arrive at certain 

 conclusions regarding the prognosis based upon a study of 

 the agglutinative phenomena. Their conclusions are : 



1. Prognosis is unfavorable if the agglutinating reaction is per- 



sistently low. 



2. Also if the agglutinating reaction rapidly fall from a high figure 



to almost zero. 



3. A persistently high and rising agglutinating reaction sustained 



into convalescence is favorable. 



4. A long illness may be anticipated if the agglutination figure, at 



first high, decreases considerably. 



The agglutination reaction appears early, and is available 

 by the end of the first week, and persists often for years 

 after convalescence. 



Pathogenesis. The micro-organism is not pathogenic 

 for mice, guinea-pigs, or rabbits, but is fatal to monkeys 

 when agar-agar cultures suspended in water are injected 

 beneath the skin. 



The micro-organism usually seems to be absent from the 

 circulating blood, though Hughes has cultivated it from the 

 heart's blood of a dead monkey. 



Bruce not only succeeded in securing the micro-organism 

 from the cadavers of Malta fever, but has also obtained it 

 during life by splenic puncture. 



Accidental inoculation with micrococcus melitensis, as by 

 the prick of a hypodermic needle, is almost invariably fol- 

 lowed by an attack of the disease. Six cases of this kind 

 occurred in connection with bacteriologic work on Malta 

 fever at Netley and two additional at the Royal Naval 

 Hospital at Haslar and in the Philippines. 



Treatment. The treatment of Mediterranean fever by 

 means of bacterio-vaccines has been attempted with what 

 seem to be glittering results by Bassett-Smith.|| 



* "Lancet," 1897, March 6; "Brit. Med. Jour.," 1897, May 15. 



t Ibid., 1899, n, p. 701. 



J "British Med. Jour.," 1902, n, p. 86 1. 



See Wright and Windsor, "Jour, of Hygiene," n, 1902, p. 413. 



|| "Journal of Hygiene," vii, 1907, p. 115. 



