532 PATHOGENIC MICROORGANISMS 



the disease is by far the more frequent. In man the disease is similar 

 to that of the horse except that the point of origin is more frequently 

 in some part of the skin rather than in the nasal mucosa, and the 

 clinical symptoms differ accordingly. The onset is usually violent, 

 with fever and systemic symptoms. At the point of infection a nodule 

 appears, surrounded by lymphangitis and swelling. A general papular 

 eruption may occur. The papules may become pustular, and the 

 clinical features may thus simulate variola. This type of the disease 

 usually ends fatally in eight to ten days. The chronic form of the 

 disease in man is much like that in the horse, but is mo i-e frequently 

 fatal. 



The histological appearance of the glanders nodules is usually one of 

 diffuse leucocytic infiltration and the formation of young connective 

 tissue which preponderates more and more as the disease becomes 

 chronic. Virchow has classed these lesions with the granulomata. 

 From the center of such nodules B. mallei may often be obtained in pure 

 culture. The nodules may be generally distributed throughout the 

 internal organs. The bacilli themselves are found, apart from the 

 nodules, in the nasal secretions, and occasionally in the circulating 

 blood.^ 



The bacteriological diagnosis of glanders may be made by isolating 

 and identifying the bacilli from any of the above-mentioned sources. 

 When superficial nodules can be opened for the purpose of diagnosis this 

 may prove an easy task. The most diagnostically helpful medium in 

 such cases is potato. In a majority of cases, however, isolation is ex- 

 tremely difficult and resort must be tad to animal inoculation. The 

 most suitable animal for this purpose is the male guinea-pig. Intra- 

 peritoneal inoculation of such animals with material containing glanders 

 bacilli leads within two or three days to tumefaction and purulent 

 inflammation of the testicles. Such an experiment, spoken of as the 

 "Strauss test," ^ shoilld always be reinforced by cultural examination 

 of the testicular pus, the spleen, and the peritoneal exudate of the 

 animals employed. 



Tozin of Bacillus mallei. — The toxin of B. mallei, or mallein, belongs 

 to the class of endotoxins. The toxic products have been invariably 

 obtained by extraction of dead bacilli.' Mallein differs from many 

 other bacterial poisons in being extremely resistant. It withstands 



1 Wassilieff, Deut. med. Woch., 1883. 



^Strauss, Arch, de m6d. exp., 1889. 



' Kresling, Arch, d. sci, biol., J892; Preuser, Berl. thierarzt. Woch., 1894. 



