l8o ANTHRAX 



CHAPTER XVII 



ANTHRAX 



Though anthrax is not uncommon in cattle, sheep, and some 

 other animals, it is not a disease which occurs very frequently in 

 man, except amongst those engaged in certain trades. 



Experiments. 



Raimbert (1869) and Davaine (1870) placed flies on infected 

 material, and proved by inoculation experiments that the bacilli 

 were present on their limbs. Celli (1888) showed that the bacilli 

 recovered from the faeces of infected flies still retained their 

 virulence. Sangree (1899) demonstrated that if a fly walked 

 over an anthrax culture, and was then placed on a sterile agar 

 surface the latter became infected. Buchanan (1907) carried out 

 similar experiments, and also found that a specimen of C. vonii- 

 toria could infect Petri dishes of agar by walking over them after 

 having walked over the skinned and gutted carcase of a guinea- 



PLATE XX 



Fig. I. — Photograph (^ nat. size) of an agar plate before incubation, inoculated with 

 the organs of four flies infected with B. anthracis. The cultures from each fly are 

 separated from each other by lines drawn on the bottom of the plate, and are 

 numbered I, II, III, IV. In each case the parts inoculated with the crop and 

 gut contents and the fluid expressed from the proboscis are surrounded by circles 

 and marked C, G and P respectively. The legs, wings and heads have been 

 separately inoculated in each case. 



Fig. 1. — Photograph of the same plate after 24 hours' incubation at 37° C. Large 

 anthrax colonies have developed in the places inoculated with the crop and gut 

 contents of fly III. Colonies of B. anthracis and other organisms have grown 

 round several of the other inoculated portions of the plate. 



Fig. 3. — Photograph of a plate culture made from the legs, head and contents of the 

 alxlomen of a fly, which died of infection with E. inuscic 14 days after feeding on 

 syrup infected with the spores of B. anthracis. The body was subsequently kept 

 in a glass bottle, and the culture made 155 days after death. Colonies of 

 B. anthracis have developed round the legs and several portions of the abdominal 

 contents. (From Graham-Smith, Reports to Local Government Board, No. 40, 

 lyio.) 



