infection in victims surviving the primary effects of snake poisoning, and 

 W. K. V/elch, in 1392 j discovered that rattlesnake venom causes "blood to 

 lose its bactericidal power. Normal "blood seram destroys thousands of ■ 

 "bacteria, while venomized serum, does not possess this power. 



Some laiowled|:e of the action of crotaline venoms is of ^^reatest 

 importance to American physicians, as 99 percent of the cases of snake 

 bite treated in the United States are caused by pit vipers. At the present 

 time extensive experimental use is being made of the venoms of the cobra, 

 vipers, and crotaline snakes in the alleviation of t"ne pain accompanying 

 malignant grov/ths such as cancer and in the treatment of arthritis. One 

 of the great possibilities of the use of venoms in medicine undoubtedly 

 lies in the ability of certain of the venom.s to accelerate coagulation of 

 haemophilic blood. 



MORTALITY 3SSULTING FHCM Si\AK3 BITE 



The average mortality from bites of the American venomous sna-tes 

 was estimated by T7illson in 1908 as little miore than 10 percent of those 

 bitten, but with modern m.ethods of treatment fatalities have been reduced 

 to less than 4 percent. A study carried on by the Antivenin Institute of 

 America under the direction of Afranio do Amaral (1927) has shown, however, 

 that the danger from snake bite has been underestimated. It y;as found that 

 in the course of one year (July 1926 to J"une 1927) in Texas som.ething like 

 150 cases were reported. Of these, antivenin was given in 83 cases, with 

 78 recoveries and 5 deaths, the death rate being 6 percent. The death 

 incidence was higher than would have been the case had the antivenin been 

 administered sooner. In the remaining 67 cases, in which the antivenin was 

 not injected, 23 died, the death rate being 34.3 percent. In the North- 

 eastern States it has been estimated that the mortality rate, in the 

 absence of special treatment, is 10 to 13 percent of those bitten, the 

 increase being largely dxie to the copperhead. In G-eorgia, Florida, and 

 Alabama the average mortality is 18 to 25 percent. In Texas, New Mexico, 

 and Arizona the death rate is somewhat "nigher, no doubt beca'^se of the 

 presence of the western diamondback rattler ( Crotalus atrox ) , and ranges 

 from 25 to 35 percent of those bitten. Estimates ranging from 100 to 1,500 

 cases in the United States eac"h year of persons bitten by venomous snakes 

 show the present uncertainty that exists in regard to the prevalence of 

 accidents of this sort. 



The tendency of rattlesnakes to rattle whenever disturbed and to 

 continue the rattling as long as the disturbing influence is present also 

 explains why victhns are not more numerous. The timber rattler has been 

 known to keep up its rattle for half an hour with but few intermittent 

 momentary pauses. The fact that the water moccasin lives in unfrequented 

 swamps and the harlequin snakes have burrowing habits and small-sized mouths 

 acco^jnts for the infrequency of bites attributed to these species. 



In fatal cases the time intervening between the bite and death varies 

 greatly. Cases terminating fatally within a few irdnutes do occur, though 

 fortijnately they are very rare. There is a record (Eoberts) that a boy 

 7 years old bitten by a rattlesnake on the cheek below the eye pitched 

 forward dead before an eye witness could reach him. A little girl 3 years 



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