(310 Epizootic CV'it'bro-spiiial Meninyilis. 



ism. Christiani found an exactly similar orgaiiism in primary spo- 

 radic meningitis in the horse, and in a goat (see page 625). 



In an outbreak in Minnesota, Wilson & Brimhall found an organ- 

 ism corresponding with the Micrococcus meningitidis cerebrospinalis of 

 Weichselbaum in the central nervous system of a cow. In other out- 

 breaks in cattle, horses, sheep and pigs only Frankel's diplococcus pneu- 

 moniffi could be found. The latter organism was also found at the same 

 time in men dead of cerebo-spinal meningitis. Horses inoculated sub- 

 cutaneously, intravenously, subdurally, in the brain and lumbar portion 

 of the spinal cord, all died showing typical symptoms of cerebrospinal 

 meningitis; and diplococci were found in pure culture in the central 

 nervous system of the experimental animals. A similar organism was 

 found by Trambusti in the meningeal exudate of a sheep, by Manfred 

 d'Ercole in two calves, and Zangheri in a horse. 



Bacteriological investigations have, therefore, not as yet 

 given any perfectly satisfactory results, although it is probable 

 that Siedamgrotzky & Schlegel, Johne, Ostertag, Streit, Grimm, 

 Christiani, Marcq, and possibly also Wilson & Brimhall, were 

 dealing with the same organism which had in some way varied 

 its characters somewhat. Further investigations are necessary 

 to decide whether the cause of the socalled Borna disease is 

 always present in cases of cerebro-spinal meningitis in the horse, 

 and whether it plays any part in the production of the disease 

 in other species, at least in a proportion of cases. The obser- 

 vations of Prietsch, Walther, Proger and AVilson & Brimhall 

 appear to indicate that this is the case. A solution is also re- 

 quired to the question as to what relationship exists between 

 the organism described by Johne and others to the diplococcus 

 intracellularis of the human subject. According to Johne the 

 two may be distinguished by the fact that the organism which 

 occurs in the horse may be present in the central nervous sys- 

 tem without causing lesions but simply an intoxication. Ac- 

 cording to Ostertag there is no connection between the two or- 

 ganisms. Christiani, on the other hand, was unable to find any 

 differences between the streptococcus found by him and the 

 diplococcus intracellularis of Weichselbaum. 



There is the possibility that epizootic cerebro-spinal men- 

 ingitis in the lower animals is not an etiological entity, and as 

 the diplococcus intracellularis and the d. pneumoniae occur in 

 man, each may be responsible for epidemics of the disease in 

 the human family. 



Natural Infection. Under natural circumstances infection 

 takes place through the medium of infected water or food. The 

 fact that at the postmortem there is usually found catarrhal 

 pharyngitis and gastro-enteritis suggests the possibility that, in 

 spite' of the negative results so far obtained experimentally l)y 

 feeding, the infective material enters by the alimentary canal 

 and in some unknown way gains access to the blood stream and 

 thus is enabled to exercise its toxic effect. 



