HOW DOUBLE TREATMENT IS GIVEN 389 



I investigated one case, for instance, where the farmer had given 

 the treatment himself, and where virus alone had been adminis- 

 tered and the serum not administered until the animals began to 

 get sick from the use of the virus. In another case equal parts of 

 virus and serum had been given, and in any number of cases 

 serums had been used which were of questionable strength and 

 not of tested power to prevent the disease. 



If you are going to use a cheap and untested serum, use it by 

 the single method only. You may be lucky enough that the herd 

 in which it is given will not be exposed to the germs of cholera, 

 and in this case, if the serum is not too dirty, you will be able to 

 get through with no bad effects, although you have actually done 

 no good. 



When you decide to give the double method of treatment you 

 must be absolutely sure of your serum. You are placing in the 

 body of the animal a dose of hog-cholera virus which will most 

 certainly produce cholera and kill the animal within two weeks 

 at most if not properly protected by a powerful serum. The 

 results of the double method of treatment depend absolutely upon 

 the quality of the serum, and no serum should be used in applying 

 the double treatment unless it has been previously tested against 

 the virus in the Uving animal, and found to have the power to 

 protect from bad effects when doses of 2 c.c. of the virus blood are 

 used. 



If this precaution is taken to ensure a perfectly reliable serum 

 there is absolutely no danger of bad results in a herd in which the 

 double treatment is used. In the United States Government 

 experimental work in the states of Iowa, Indiana, Missouri, and 

 Nebraska the simultaneous method of treatment has been made 

 use of very largely, and the results have been uniformly pleasing. 

 No outbreaks of cholera have occurred in animals that have been 

 given this method of treatment, and no deaths have been traceable 

 to this cause. 



In order to ensure a permanent immunity as a result of this 

 method of treatment it must be made sure of that the virus blood 

 used is really capable of producing disease. Remember that it 

 is due to the action of this virus blood that the cells of the body 

 take up the work of manufacturing germ-destroying bodies, and in 



