744 PATHOGENIC MICROORGANISMS 



into suitable animals produces no botulismus, and intravenous injec- 

 tion or feeding of the bacilli alone, may not produce symptoms. 

 The conclusion drawn by Von Ermengem was that the toxin could 

 not be produced in the bodies of mammals. 



The toxin is potent for monkeys, rabbits, guinea-pigs, cats, and 

 various birds. Dickson found chickens highly susceptible, and also 

 found that dogs were not as resistant as formerly thought to be. 

 The most susceptible animals seem to be mice, guinea-pigs and 

 monkeys ; rabbits, cats, dogs and rats are relatively resistant. 



In studying various isolations of the Bacillus; Dickson found that 

 the strains isolated by him were not entirely homologous, and that 

 the toxins produced by some of them were not neutralized by the 

 antitoxin produced with others. Burke also found two types that 

 produced heterologous toxin and claims that the strains could be easily 

 identified by a toxin-antitoxin test. 



Pathology. In animals, according to Von Ermengem there is a 

 general hyperemia of the organs and especially of the nervous 

 system. Dickson has made a thorough review of the pathological 

 work done by Von Ermengem, Vander Stricht,* Marinesco 51 and 

 others, 52 summarizing the pathology as follows: In the central 

 nervous system the meninges at the base of the brain, especially 

 around the pons and the medulla, are usually more markedly con- 

 gested than at the cortex, and there may be hemorrhage in the 

 upper part of the cord and at the base of the brain. The lungs may 

 be hyperemic, heart muscles flabby, but nothing characteristic. An 

 important and regular lesion found by Ophuls 53 was multiple throm- 

 bosis in both the arteries and veins of the central nervous system. 

 Ophuls believes this is due to a certain vasodilation with slowing 

 of the blood stream due to a powerful paralyzing effect of the poison 

 on the unstriped muscles. The thromboses are particularly common 

 at the base of the brain. Ophuls, too, differs from others in believing 

 that the specific action of the toxin on the nerve cells themselves 

 has been very much exaggerated in that his histological examina- 

 tions of the brains of fatal cases did not bear out this earlier opinion. 



Transmission and Occurrence of Botulismus, Kempner and Pol- 



* Stricht, Quoted from Van Ermengem, in Kolle and Wassermann. 

 51 Marinesco, Compt. rend, de 1'acad. des sci., Nov., 1896. 

 62 Kempner und Pollack, Deut. med. Woch., xxxii, 1897. 



63 Ophuls, with Wilbur, Arch. Int. Med., 14, 1914, 589. 



