MORTALITY OF TETANUS 



159 



acute and chronic, in the hospitals of New York 

 City, gives a mortality of 83 per cent, in time of 

 peace. The fairest estimate seems to be, for acute 

 cases, at least 88 per cent., and for the sub-acute 

 and chronic cases, 40 per cent. 



" The prognosis of tetanus is in direct ratio to 

 the shortness of the incubation-period, and to the 

 rapidity and intensity of the development of the 

 symptoms. In judging of the results of antitoxin 

 we must, therefore, divide the cases into acute, i.e., 

 all those with an incubation-period of less than ten 

 days, or with a longer incubation, but with very 

 acute onset, and those with an unknown incubation, 

 but with an acute course ; and chronic, i.e., with 

 more than ten days' incubation, or with a less than 

 ten-day incubation, but with a slow, moderate onset 

 of symptoms, and those with an unknown incuba- 

 tion and mild course. The following cases of 

 tetanus, treated with antitoxin, comprise published 

 and unpublished cases. We have a total of 279 

 cases, with a mortality of 44.08 per cent. : but of 

 these we must rule out 17 cases — 4 deaths from 

 intercurrent diseases, 8 deaths in cases in which 

 the antitoxin was given but a few hours before 

 death, and 5 recoveries in which antitoxin was 

 not given until after the twelfth day (as they 

 probably would have recovered without it). We 

 have left 262 cases, with 151 recoveries, and 111 

 deaths, a mortality of 42.36 per cent. Dividing 

 the cases into acute and chronic, we have 124 acute 

 cases, with 35 recoveries and 89 deaths, a mortality 

 of 71.77 per cent., and 138 chronic cases, with 116 

 recoveries and 22 deaths, a mortality of 15.94 per 

 cent. In interpreting critically these statistics, we 

 see that in acute cases the mortality is but slightly 

 reduced, being but 72 per cent, instead of 88 per 



