114 



BACILLUS ANTHRACIS. 



Davaine. Pollender. (1849). 



SYNONYMS OF ANTHRAX. SPLENIC FEVER (IN CATTLE) : WOOL-SORTER* S 



DISEASE, MALIGNANT PUSTULE (IN MAN) ; MILZBRAND (Germ.} ; 



CHARBON., SANG DE KATE (/*>.). 



Origin. In the blood and tissues in anthrax. 



Form. Large, clear, homogeneous rods, with slightly rounded 

 ends ; si/e varies witli different media, but the length is less 

 than the diameter of a blood cell. Occurs in blood in short threads 

 of 2-4-0 cells, which may show slightly swollen ends. In bouillon 

 and on agar forms long threads. Involution forms. 



Motility. lias no motion. 



Sporulation Forms median, oval spores, without enlarge- 

 ment of cell. Alter long cultivation it may lose the property of 

 forming spores asporogenic variety. I; such cases the addition of 

 fo-1 drop of Cu(OH)2 to an agar tube favors spore formation. 

 Optimum temperature, 30 C. Not formed below 18 C. Spores 

 possess variable resistance. Spores not formed within the body. 



Anilin Dyes. Stu.n readily, also by Gram's method. 



Growth. Is rapid. 



<;<'lii/iti !'!(cs. Deep colonies form round, granular, yellowish-brown 

 masses, with irregular borders. Surface colonies are very characteristic, and 

 according to the consistency of the gelatin the border is fibril I tiled, or shows 

 very wavy strands of threads Medusa head. Liquefy. 



Mich Cultures. .Short threads radiate from the line of inoculation into 

 the surrounding" gelatin, imparting a brush-like appearance. Cup-shaped 

 liquefaction forms on top and gradually extends till the contents are wholly 

 liquefied. The mass of bacteria settles to the bottom and leaves a perfectly 

 clear solution above, without scum. 



Streak Cultures. On agar, forms a dry, grayish-white growth On 

 potatoes, the growth is abundant, white, cream-like and rather dry; spores. 



Oxygen requirements. Is aerobic, but can grow in the body 

 as a facultative amierobe. 



Temperature. Grows between 12 and 45 C. Optimum :>7 . 



Behavior to Gelatin. Liquefies. 



Attenuation By heating for ten minutes at 35 C. ; ^-1 

 minute at 100. By growing at 42.5 for four weeks. By action of 

 chemicals, mercuric chloride, carbolic acid, etc. By insolation. By 

 growth under pressure. In the body of immune animals, as frogs. 



Immunity. Obtained with attenuated cultures, first and 

 second vaccine of Pasteur; with sterilized cultures; with extract of 

 thymus gland and of testes. 



Pathogenesis White mice, guinea-pigs, rabbits, sheep, cat- 

 tle, horses and man are susceptible. Dogs, old white rats, birds 

 and frogs are insusceptible. Subcutanec us application kills in 24- 

 48 hours. Post-mortem shows subcutaneous oedema and enlarged 

 spleen. Bacilli everywhere. 



Infection. (1) Through the food, presence of spores, Intes- 

 tinal anthrax in sheep and '.attle. (2) Through wounds, Inocu- 

 lation anthrax in man (malignant pustule), (3) Through the air, 

 Lung anthrax in man, the wool-sorter's disease and possibly rag- 

 picker's disease. 



