Short History of Infectious Anemia. 9 



out most profitably the experiments of prevention. As 

 the first step all the horses were carefully examined. 

 Those which showed even the slightest sign of the 

 symptoms characteristic of the disease were bought and 

 killed. As the result of this 107 horses of the village 

 were reduced to 45, 24 having died of the disease and 

 38 having been killed. This method proved to be very 

 effective, since not a single horse of those remaining 

 succumbed to the disease, though some have had a 

 weak form of it. This seems to give an important side- 

 light that, though one infected horse is able to affect 

 the whole herd, yet those animals which have had a 

 slight form of the disease seem to acquire immunity 

 and do not show any further symptoms at all. 



We regret that we do not have exact statistics of 

 yearly losses in various localities. However, the following 

 numbers show the totals of cases reported by Local Go- 

 vernors since the establishment of the Commitee : 



1910 341 horses. 



1911 376 „ 



1912 359 „ 



1913 263 „ 



It may be added that the above cases are those 

 which were reported to the Local Governors by the horse 

 owners and veterinary practitioners. Besides these, there 

 must have been cases which remained unreported due 

 either to the negligence on the part of horse owners or 

 to the lack of regulations for reporting. In any event 

 we can estimate without grave mistake the whole number 

 of patients in Japan to be between 400 and 500. Lately 

 the cases are decreasing in number due partly to the 

 fact that the disease has already spread as extensively 

 as it possibly can and partly to the immunity acquired 

 by the horses of affected districts. 



