Bacillus Tetani, Nicolaier (1884). 

 TETANUS, lock-jaw; wundstarbkkampf ((?erm.); tetanos (i^r.). 



Origin. — ^Pound in animals that die of tetanus after inoculation 

 with earth; in traumatic tetanus of man and animals; in head- 

 tetanus; tetanus of new-born. Present in intestines. 



Form.— Large, narrow rods with rounded ends; may form threads. 



Motility. — Is motile. May show long spirals or giant whips. 



Sporulation.— Occurs rapidly, in 24-48 hours at 37°. Forms ter- 

 minal spores, with enlargement — drum-sticks. 



Anilin dyes. — Stain rapidly. Gram's method is applicable. 



Growth. — This is slow. 



Plates. — At ordinary temperature colonies develop in gelatin in 4-7 days, and resem- 

 ble those of the Hay bacillus or of Proteus. The gelatin is slowly liquefied and gas pro- 

 duced. On agar plates the colonies appear as faint clouds which, under the microscope,. 

 are seen to be oval and partly surrounded by a whorl of threads which are finer than those 

 of other anaerobes. 



Stab culture. — Development restricted to the lower part of the tube. Cultures in 

 ^Incose gelatin tubes show along the line of inoculation a cloudy growth, radiating outward 

 into the surrounding gelatin; resembles that of the Root bacillus. Eventually the gelatin 

 is liquefied. Gas bubbles present. In glucose agar at 37° the growth is sometimes indis- 

 tinct and shows radiations. 



Streak culture.—On glucose agar the growth is rapid and is practically invisible. 



Bouillon.— At 37° becomes diffusely cloudy and remains so for several days; event- 

 ually the growth settles to the bottom, forming a scarcely visible sediment — distinction from 

 the preceding anaerobes. 



Glucose gelatin, colored with litmus. — At 37" becomes permanently liquefied; a very 

 small sediment forms, and the culture remains blue, showing absence of acid formation- 

 distinction from preceding. 



Milk. — It grows well in milk without inducing any change. Does not invert starch. 

 The growth on potato is invisible. 



Oxygen requirements. — It is an obligative anaerobe and grows in 

 vacuum, hydrogen, nitrogen, and carbonic acid. 



Tkmperature. — No growth below 16°. The optimum is about 38°. 



Behavior to gelatin. — Liquefies. 



Aerogenesis. — Gaseous products; disagreeable odor; H2S. 



Attenuation. — Partial loss of virulence by culture. 



Immunity. — Iodine trichloride; thymus bouillon cultures; injec- 

 tion of filtered culture; of purified toxin; blood-serum of artificially 

 immunized rabbits, horse, sheep, dog; milk of immunized goat. The 

 nucleohiston from the thymus gland destroys the tetanus toxin. 



Pathogenesis. — Man, horse, sheep, guinea-pigs, young cattle, 

 goats, white mice and white rats, are susceptible. Rabbits and dogs 

 are less susceptible. Ducks and chickens are immune. It is not in 

 the blood but is present at the point of inoculation, although in small 

 numbers; at times it may be wholly absent. Intensely poisonous pro- 

 ducts, 'i'he filtered bouillon culture in a dose of 0.0002 c.c. may kill a 

 mouse, and 0.002 c.c. may kill a guinea-pig. The strictly pure tetanus 

 spores cannot produce the disease. Mixed infection. 



Infection.— Occurs through wounds. Poisoned arrows of the 

 New Hebrides contain tetanus and malignant edema spores. 



Diagnosis. — The detection of the bacillus is difficult because of its 

 scarcity, and because of the presence of other anaerobic and aerobic 

 bacteria. The pus should be removed from the wound with a sterile 

 drawn-out glass tube pijjette and transferred to glucose . litmus gela- 

 tin. A loopful of this dilution should be transferred to each of 8 or 10 

 tubes of liquefied glucose agar. These are then poured into Petri 

 dishes and developed in hydrogen. The characteristic colony is oval, 

 one end of which is surrounded by a whorl of threads. 



The original glucose litmus g'elatin is developed at 35° and a por- 

 tion is then injected under the skin of a guinea-pig, or a white mouse. 



A portion of the pus should be stained direct and examined for 

 the long slender tetanus bacilli and for "drum-sticks." 



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