2l82 



ULCERATION 



The important researches of KeysseHtz and Mayer, and the more 

 recent ones of Wolbach and Todd, confirm Prowazek's work. 



Spiroschaudinnia vincenti Blanchard, 1906 (synonym, Spiroschaudinnia 

 schaudinni Prowazek, 1907). — This is a spiral-shaped organism, very actively 

 motile, its length varying between 10 and 22 fj,, though much shorter or 

 longer individuals may be met with. The coils are few in number, and 

 elongated. The organism possesses a well-marked undulating membrane, 

 which is best brought into evidence by using Loffler's flagellar stain. A 

 delicate, rather short flagellum is occasionally seen at one of the extremities. 

 Forms undergoing longitudinal division are frequently observed. Prowazek 

 distinguishes, also, male and female forms. Variously shaped regressive 

 and rest forms may be seen. According to Prowazek, Spiroschaudinnia 

 vincenti, apart from being more slender, has the greatest resemblance to the 

 spirochaete which Prowazek himself and Hofman have described in a form of 

 balanoposthitis. 



The 5. vincenti is often found mixed with other types of spirochaetes, some 

 slender, some thick. 



According to Le Dantec, Brault, Vincent, and others, ulcus tropicum is 

 identical with the so-called ' hospital phagedaena ' which used to rage in hos- 

 pitals of all countries before the antiseptic era. In our opinion ulcus tropicum 

 is a separate disease, though occasionally, owing to secondary infections, it 

 may take phagedaenic characters similar to those found in hospital gangrene. 



Inoculation Experiments — Communicahility. — Experiments to in- 

 oculate the disease in men and in the lower animals have been made 

 by several authors. Blaise inoculated himself with the secretion 

 of a case of ulcus tropicum, but no ulcer was produced — only a 

 slight superficial, purulent lesion, probably due to pyogenic cocci 

 present as secondary infectious agents in the secretion which had 

 been used for the inoculation. Blaise tried to inoculate the disease, 

 also, in guinea-pigs, but without any definite result. Similar experi- 

 ments on the lower animals by Jourdeuil and Gayer failed. Hal- 

 berstadter tried to reproduce the affection in monkeys (orang- 

 outang and Macacus cynomolgus), but without success. 



It would seem, therefore, that, to a certain extent, the disease 

 is not directly contagious. It is probable that some insects or 

 other blood-sucking vermin may play an important role in the 

 transmission of the disease. In Ceylon, patients often state that 

 the ulcer developed at the site of a leech-bite. Leeches are ex- 

 tremely common in Ceylon and other tropical countries. Prowazek 

 in Java has examined many leeches, but he never found any spiro- 

 chaetes except once. The spirochaete observed, however, was quite 

 different from Spiroschaudinnia vincenti. Prowazek examined, 

 also, on many occasions the mud of rice-fields, but of spirochaetes he 

 found only S. plicatilis, and once a very thin, short, very actively 

 mobile spirochaete. 



Predisposing Causes. — A hot, damp climate is said to have a pre- 

 disposing influence, as cases of ulcus tropicum occur more frequently 

 in the hot rainy season and marshy lowland localities rather than 

 in dry or higher regions. It may be that it is in hot, marshy places 

 that the carriers of the infection thrive. 



The disease is very common among the poorer classes of the 

 population, who go barefooted and wear but scanty clothes. We 



