CHAPTER XXXIV. 

 THE BACILLUS OF SOFT SORE. 



Introduction. 



Section I. Experimental infection, p. 513. 



Section II. Morphology and cultural characteristics, p. 514. 



Section III. Biological properties, p. 515. 



Section IV. Detection, isolation and identification of the bacillus, p. 515. 



THE bacillus of soft sore was discovered by Ducrey and more completely 

 studied by Unna, Ch. Nicolle, Queyrat, Bezan9on and others. 



In pus from the chancre the bacillus is generally found in association with 

 other organisms (staphylococci, micrococcus tetragenus, bacillus cutis communis of 

 Ch. Nicolle and gonococci). The bacillus is found between the cells of the connective 

 tissue of the dermis, but does not penetrate into the fixed ceUs of the tissues nor 

 gain access to the vessels ; when the lesion is healing numerous bacilli will be found 

 in the leucocytes. The pus becomes less and less pathogenic as the sore cicatrizes. 



The bacillus is present in pure culture in the bubo, but as a rule (92 times out of 

 100, Rille) cannot be detected on microscopical examination of the pus the sterile 

 pus of Strauss though its presence there can be demonstrated by sowing cultures 

 (Bezanon, Griffon and Le Sourd, Simon). 



SECTION I. EXPERIMENTAL INFECTION. 



Man. If a little pus from a chancre or a culture of the bacillus be inocu- 

 lated a typical soft sore is produced in the human subject. A first infection 

 confers no immunity, and the sore is indefinitely re-inoculable time after 

 time in the same individual. 



Inoculation for experimental purposes should be made into the outer surface of 

 the arm or into the thighs but not on to the abdomen below the umbilicus. 



It is best to lightly scarify the epidermis over an area of 2 or 3 mm. with a sterilized 

 needle charged with the virus ; the skin should be scratched sufficiently deeply to 

 draw a drop of blood. The site of inoculation should be protected from friction and 

 from all source of contamination : the most convenient method of doing this, and 

 one which allows of the lesion being watched, is to cover the part with a sterile 

 watch-glass which can be held in position by a piece of gauze in the centre of which a 

 hole is cut so that the glass is only covered at its edges ; the gauze is fixed to the 

 glass and to the skin with collodion. The whole is covered with a little wool and 

 bandaged. The lesion commences to develop about the end of the first day and is 

 characteristic about the fourth to the sixth day. 



Animals. Laboratory animals are immune but monkeys (Macacus and 

 Bonnet monkeys) may be infected experimentally. Tomasczewski has 

 successfully inoculated man with cultures from an experimental sore in 

 a monkey. 



2K 



