520 THE ANAEROBIC BACTERIA 
hut they do not as a rule penetrate deeply into the body, although 
Ilochsinger' and Creite- have found the organisms at autopsy in a very 
few instances in the spleen and heart blood. 
Tarozzi'^ and Canfora^ have studied the fate of tetanus spores after 
subcutaneous inoculation into guinea-pigs and rabbits very carefully. 
They find the spores may be transmitted rather rapidly to the paren- 
chymatous organs, liver, spleen, and kidneys principally, where they 
may remain alive but latent for seven to eight weeks. Tulloch-^ has 
found tetanus bacilli in a war wound eight hundred and eighty-two 
days after the injury was received. If trauma or injury resulting in 
inflammation occurs during this time, acute or chronic tetanus may 
result. These observations suggest a possible explanation for the 
so-called cryptogenetic, idiopathic, or rheumatic tetanus; the intestinal 
tract is supposed to be an occasional portal of entry, thus explaining 
another source of cryptogenetic tetanus. 
Experimental Pathogenesis in Animals.— The disease tetanus may 
be produced in susceptible animals by injecting soil or active cultures 
of tetanus bacilli, spores mixed with tetanus toxin, or tetanus toxin 
alone. If, however, tetanus spores carefully freed from toxin are 
injected alone, tetanus frequently fails to develop. Vaillard and Yin- 
cenf^ and Vaillard and Rouget" have furnished an interesting explana- 
tion for this possibility. They find that phagocytosis plays an import- 
ant part in the removal of tetanus spores which are injected without 
tetanus toxin or other irritating substances. Polymorphonuclear 
leukocytes engulf free tetanus spores. If, however, the spores are 
introduced into the body in collodion capsules, thus protecting the 
organisms from the leukocytes, the tetanus spores develop into bacilli 
there, form toxin, and produce tetanus.* If tetanus spores are mixed 
with lactic acid, with tetanus toxin, or with other irritants, or even 
injected with saprophytic bacteria, the spores develop into tetanus 
bacilli, produce toxin and kill the animal. 
Bacteriological Diagnosis. — 1. ilffcro^fop/c.— Smears made from the 
pus of wounds in suspected cases of tetanus may show the charac- 
teristic spores of the tetanus bacilli. The organisms, however, are 
usually present in very small numbers and several smears should be 
made. Negative results do not prove the absence of the tetanus 
bacillus. 
2. C7flt2iral.—Vus from wounds scraped out with sterile curettes, or 
suspected material is placed in fermentation tubes containing bits of 
sterile tissue, according to Theobald Smith's method mentioned above, 
» Centralbl. f. Bakteriol., 1887, 2, 145. Hohlbeck: Deutsch. med. Wchnschr., 
1903, 29, 172. 
2 Centralbl. f. Bakteriol., orig., 1904, 37, 312. 
3 Ibid., 1905, 38, 619. ' Ibid., 1908, 45, 495. 
5 Medical Research Committee Special Report, Series No. 39, p. 29. 
6 Ann. Inst. Pasteur, 1891, 5, 1. 
' Ibid., 1892, 6, 385; Centralbl. f. Bakteriol., 1894, 16, 208. 
8 Metchnikoff: Ann. Inst. Pasteur, 1898, 12, 263. 
