THE TREATMENT OF AMERICAN 

 FOULBROOD 



By Jas. I. HAMBiLHTON, senior apicuUurht, in cfiarge, Division of Bee C'ulture, 



Bureau of Entomology 



CONTENTS 



Page 



Cause of the disease. _ 1 



Spread of the disease 2 



Symptoms... 3 



Otlier brood diseases sometimes mistaken for 



American foulbrood 3 



Treatment... , 9 



Burning diseased colonies '---. 9 



Disinfecting empty hives after burning . . 10 



Treatment— Continued ^**® 



Shaking not recommended 11 



Objections to the use of disinfecting solu- 

 tions 11 



Disinfecting super combs _ 11 



Treatment by State inspectors 12 



Handling and disposing of honey from 



affected colonies 13 



AMERICAN FOULBROOD is a disease of the brood of bees 

 XTL which causes series losses to beekeepers. Not only does it take 

 a heavy toll in the actual destruction of colonies and increase the 

 cost of operating an apiary, but, what is perhaps of equal import- 

 ance, the presence of disease in an apiary, or in the vicinity of one, 

 causes such mental anxiety to some beekeepers that it unquestionably 

 prevents them from succeeding in the bee industry. 



The disease is practically world-wide in its distribution and is of 

 common occurrence in the United States. All races of bees are sus- 

 ceptible. There have been statements in the beekeeping literature 

 that lead one to believe that the brood of certain strains of bees is 

 immune, but there is no evidence upon which to base this assump- 

 tion. There may be various strains of the disease, differing in viru- 

 lence, and individual colonies may react differently. Not enough 

 variation has yet been detected, however, to warrant giving such 

 suspected cases special treatment. Worker larvae are particularly 

 susceptible to the disease, although queen and drone larvae are occa- 

 sionally affected. Adult bees are immune to it. 



CAUSE OF THE DISEASE 



American foulbrood is caused by a species of spore-bearing_ bac- 

 teria known as Bacillus larvae. The living honeybee larva is its 

 only known host and the disease is transmitted primarily by means 

 of the spores. The bees that work within the hive become contami- 

 nated with these spores in attempting to remove the diseased brood, 

 and carry them from one cell to another. Once the disease has 

 spread generally throughout the brood nest, the bees cease trying to 

 remove the dead brood, and it accumulates until the colony dies 

 owing to the absence of emerging bees. 



4939° — 33 1 



