CHAPTER XVII 
THE TETANUS BACILLUS (LOCKJAW) 
I. Historical 
The bacillus tetani was discovered by Nicolaies in 1885 
and first studied and cultured by Kitasato in 1888. 
II. Morphology 
The bacillus is a slender organism, possesses spores, no 
capsules; the vegetative forms are motile and have 
flagella. Spores are developed after twenty-four to 
forty-eight hours of incubation. The spore-bearing forms 
resemble a drumstick, since the spore is usually at the 
end of the bacillus. (See Fig. 4.) 
The bacillus is Gram-positive. 
III. Cultural Characteristics 
Bacillus tetani is a strict anaerobe; it grows readily 
on meat infusion media. Gelatin is slowly liquefied, 
milk is not coagulated. 
IV. Destruction 
The vegetative (non-spore-bearing) form are readily 
destroyed by ordinary disinfectants and heat, but the 
spore-bearing forms resist dry heat at 80° C. for one 
hour and even live steam for five minutes, and it takes 
twelve to fifteen hours for a 5 per cent solution of car¬ 
bolic acid to kill them. 
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