392 TETANUS. 



matters, whenever the first symptoms of tetanus appear, large 

 doses, such as those above indicated, of a serum whose strength 

 is known, should be at once administered. In giving a prognosis 

 as to the probable result, the two clinical observations on which, 

 according to Behring, chief reliance ought to be placed, are the 

 presence or absence of interference with respiration and the 

 rapidity with which the groups of muscles usually affected are 

 attacked. If dyspnoea or irregularity in respiration comes on 

 soon, and if group after group of muscles is quickly involved, 

 then the outlook is extremely grave. In addition to these 

 points the duration of the incubation period is of high impor- 

 tance in forming a prognosis. The shorter the time between the 

 infliction of a wound and the appearance of symptoms the graver 

 is the outlook. 



The theory as to the nature of antitoxic action will be dis- 

 cussed later in the chapter on Immunity. 



Methods of Examination in a Case of Tetanus. The routine 

 bacteriological procedure in a case presenting the clinical fea- 

 tures of tetanus ought to be as follows : 



(a) Microscopic. Though tetanus is not a disease in which 

 the discovery of the bacilli is easy, still microscopic examination 

 should be undertaken in every case. From every wound or 

 abrasion from which sufficient discharge can be obtained, film 

 preparations ought to be made, and stained with any of the 

 ordinary combinations, e.g. carbol-fuchsin diluted with five parts 

 of water. Drumstick-shaped spore-bearing bacilli are to be 

 looked for. The presence of such, having characters corre- 

 sponding to those of the tetanus bacilli, though not absolutely 

 conclusive proof of identification, is yet sufficient for all practi- 

 cal purposes. If only bacilli without spores, resembling the 

 tetanus bacilli, are seen, then the identification can only be 

 provisional. 



The microscopic examination of wounds contaminated by 

 soil, etc., may, as we have said, in some cases lead to the antici- 

 pation that tetanus will probably result. 



(b) Cultivation. The methods to be employed in isolating 

 the tetanus bacilli have already been described (p. 379). It 

 may be added, however, that if the characteristic forms are not 

 seen on microscopic examination of the material from the 

 wound, they may often be found by inoculating a deep tube 



