232 BACILLUS OF TETANUS. 



for oases of tetanus. Fish-bones, wood, and any object 

 that has been partially buried in the ground for some time, 

 may convey the infection. Many cases have been recorded 

 from localities where people are accustomed to bathe, such as 

 sandy beaches, e. g., the shores of Long Island, where, as is 

 known, tetanus has followed a fish-bone injury of the foot. 



The bites of insects, such as the sand flea or the chigger, 

 may be instrumental in producing tetanus. This is particu- 

 larly common in warm countries, where the inhabitants are 

 in the habit of going barefoot. Many cases were reported 

 from Mexico, when the soldiery went without shoes or stock- 

 ings, following the bites of the chigger. The prick of a pin 

 is sufficient to cause infection. All that is necessary is a 

 penetrating wound in which the bacillus can develop in an 

 oxygen-free environment. 



Cases of tetanus are very common around the Fourth of 

 July, and usually follow an injury of the hand produced by 

 the explosion of a fire-cracker or pistol. Naturally the hand 

 of the celebrant is not very clean after a day's shooting, and 

 all the accumulated dirt is street-dirt, which may contain the 

 tetanus bacillus. The force of the explosion drives this grime 

 into the wound and tetanus results. Superficial wounds or 

 extensive open wounds are rarely followed by tetanus, because 

 the conditions in such a wound are unfavorable for the devel- 

 opment of the germ. Penetrating wounds always close imme- 

 diately after the instrument inflicting the injury is withdrawn, 

 thus leaving the bacillus in the bottom of the wound and in a 

 most favorable environment. The bottom of the wound is not 

 exposed to the air and the germ flourishes. Sometimes these 

 wounds close so tightly that it is impossible to locate them 

 even within a few hours after the injury. In such cases the 

 treatment is necessarily more difficult than when the wound 

 can be located. 



If the infection is with the tetanus germ only, very little 

 or no suppuration occurs ; but in a mixed infection suppuration 

 is always "more or less profuse. Mixed infections are always 

 serious, because they favor the development of the tetanus 

 bacillus. The aerobic organisms consume the oxygen in 

 the wound, and the tetanus bacillus is furnished with an 



