758 PATHOGENIC MICROORGANISMS 



isolated cultures. The toxin, like that of B. Welehii, has no incuba- 

 tion period. The toxin of vibrion septique often fails to produce 

 death in guinea pigs when injected subcutaneously or intramus- 

 cularly, merely producing local necrosis. Toxin production is tested 

 both in rabbits and guinea pigs by intravenous injection. 0.5 c.c. 

 of toxin injected intravenously kills a guinea pig in five minutes. 

 0.1 to 1 c.c. injected into rabbits intravenously kills them without 

 a latent period, with symptoms of respiratory disturbance, paralysis 

 and convulsions. It is difficult to establish an M. L. D. for rabbits 

 of the same v/eight owing to individual variation. In some instances, 

 death is produced immediately in one rabbit, whereas another rabbit 

 of the same weight will show severe symptoms followed by recovery. 



METHOD OF PRODUCING TOXIN. The Hygienic Laboratory obtains 

 a powerful toxin using a 0.2 per cent glucose broth containing 10 

 per cent horse serum. Robertson recommends using liver of a pig 

 dying of a vibrion septique infection with which to inoculate the broth, 

 but the difficulties of obtaining a liver without gross contaminations 

 are such that the former method is preferable. The broth is in- 

 cubated twenty-four to forty-eight hours. Care should be taken 

 in the selection of the filter since certain filters seem to hold back 

 a large percentage of the toxin. This point is emphasized both by 

 Weinberg and Seguin and by Robertson. Antitoxins are prepared 

 by injecting the toxin into horses or sheep. The French standard 

 requires that 1/1000 c.c. of the antitoxin should neutralize two fatal 

 doses of the toxin after thirty minutes incubation of the mixture 

 at room temperature. The vibrion septique antitoxin is specific; 

 it does not protect against B. oedematiens. 



OCCURRENCE. Vibrion septique has been isolated from milk. 

 Heller 23 in an excellent summary of anaerobic infections in animals 

 has shown that spontaneous infections by vibrion septique occur 

 in sheep, horses, and hogs. Meyer 24 in 1915 reported the isolation 

 of typical vibrion septique from two cases of symptomatic anthrax 

 in hogs. Cattle, according to Heller, are less susceptible to vibrion 

 septique infections than the other animals mentioned. Herbivorous 

 animals are subject to infections with vibrion septique, both follow- 

 lowing and not following demonstrable wounds, whereas infections 

 in man seem to occur only as the result of wounds. 



" Heller, Jour. Infec. Dis., 27, 1920, 385. 

 24 Meyer, Jour. Infec. Dis., 12, 1915, 458. 



