CHAPTER 15 



ERYSIPELOTHRIX AND LLSTERELLA 



Definition. 



Rod-shaped organisms with a tendency to the formation of long filaments, 

 which may show branching. The filaments may also thicken and show charac- 

 teristic granules. No spores. Motility slight or absent. Gram-positive. Slight 

 fermentative activities. Microa^rophilic. Usually parasitic. 



The type species is Erysipelothrix rhusiopalhice, the causative organism of swine 

 erysipelas. 



The first member of this group to be described was the bacillus of mouse 

 septicaemia, Erysipelothrix muriseptica ; it was found by Koch in 1880 in the 

 blood of mice that had been injected subcutaneously with putrefying blood. In 

 1882 Loeffler (1886) observed a similar bacillus in the blood vessels of the skin 

 of a pig that had died of swine erysipelas. [It is possible that the bacillus observed 

 four months previously by Thuillier (Pasteur and Thuillier 1883) in pigs dying of 

 rouget was the same organism as that described by Loeffler, but this is not 

 absolutely clear.] Another organism closely allied to Ery. rhusiopathicB was found 

 by Rosenbach in cases of human erysipeloid. Subsequent workers have recorded 

 the presence oi Erysipelothrix in outbreaks of polyarthritis in sheep and joint-ill in 

 lambs, and in occasional infections of cattle, horses, turkeys, peacocks, and man 

 (see Beaudette and Hudson 1936, Paterson and Heatley 1938, Greener 1939). 

 There is also reason to believe that it is a not uncommon parasite of fish, though 

 conclusive evidence of this is still lacking (Klauder 1926, 1932). Schoop (1936), 

 for example, who recorded its isolation from fish, used the mouse inoculation 

 method, so that it is impossible to be certain whether the organisms came from 

 the fish or from latently infected mice. 



In 1926 Murray, Webb, and Swann at Cambridge described a disease of rabbits 

 characterized by a large-mononuclear leucocytosis, and caused by a small Gram- 

 positive non-sporing bacillus which they termed Bad. monocytogenes. The same 

 organism has since been isolated by a number of workers from various diseases 

 in animals and man characterized most often by a generalized infection tending 

 to localize in the liver, myocardium, or central nervous system (see p. 1287). For 

 this organism Pirie (1927) suggested the generic name of Listerella. Without 

 for the moment discussing the appositeness or the validity of this name, we may 

 point out that Erysipelothrix rhusiopathiw and Listerella monocytogenes resemble 

 each other in so many respects that it is convenient to describe them together. 



Habitat. — Enough has already been said to indicate the wide range of animals 

 infected by these organisms. Though both of them appear to be mainly parasites, 

 Ery. rhisiopathice is said to be present in the slime surrounding the body of 

 various fish (Klauder el al. 1926, Klauder 1932, Schoop 1936), and in sewage 

 derived from abattoirs (Hettche 1937). 



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