12 



of swine in this country can not be made effective under the conditions 

 which exist in the West and other regions where hog-raising is expensive. 



As far as our present knowledge extends, treatment of existing cases 

 is utterly futile. There remain, therefore, to be considered but two 

 alternative means of prevention — quarantine and extermination of in- 

 fected hogs with their surroundings, or, on the other hand, some form 

 of preventive inoculation. 



The vast importance of the subject calls for an exhaustive investiga- 

 tion as early as possible of this latter means, for the former is very diffi- 

 cult of application. 



Some of the tests made in Nebraska under the direction of Dr. 

 Billings certainly give promise of great possibilities in this direction. 

 It is the opinion of the Commission, however, that an attempt to pro- 

 duce immjunity from " hog cholera" artificially by the use of the living 

 germs of the disease, either through the stomach or through hypoder- 

 mic inoculation, is very objectionable and involves a serious risk of 

 more widely extending the disease and increasing rather than dimin- 

 ishing the alrea^'ly enormous losses therefrom ; for every hog thus 

 treated becomes for a time at least a center of infection from which an 

 epidemic may directly or indirectly spread widely. Furthermore, the 

 use of the living germs seems, at least in many instances, to i)erma- 

 nently stunt the growth of the pig. Experience acquired in recent 

 years shows that the chemical products of certain disease-producing 

 germs in artificial cultures possess the same power to create immunity 

 as do the living germs themselves; and some incomplete experiments 

 performed by ourselves and others seem to strongly indicate that the 

 chemical products of the '^ hog cholera" germ in artificial cultures also 

 possess a similar power. 



if further investigations shall prove this to be an indisputable fact, 

 then, in our opinion, a safe, harmless, efficient, and extremely practical 

 means of preventing ^' hog cholera," free from any risk of thereby ex- 

 tending the disease and continuing the enormous losses at present suf- 

 fered by our countrymen, will soon follow. 



We have reason to believe that the threshold of such an important 

 discovery has already been crossed ; and we therefore earnestly advise 

 that thorough and exhaustive investigation be as rapidly as possible 

 made in this direction and without stint of money or hampering limita- 

 tions of time. 



The undersigned regret that the departure of one of their number for 

 Europe before the draughting of this report has made it impossible for 

 the entire Commission to sign it. 



KespectfuUy submitted. 



E. O. Shakespeare, Chairman, 



T. J. BURRILL. 



Washing-ton, D. C, August 1, 1889. 



