l"LL.INOIS STATE BEE-KEEPERS' ASSOCIATION 



157 



Preexisting Disease. — This factor has 

 very little, if anything, to do with bee 

 diseases. By preexisting disease we 

 mean that when an individual passes 

 through an attack of a disease, the dis- 

 ease predisposes that individual to 

 other diseases. This is illustrated in 

 various human and animal diseases. 

 In bee diseases, we do not know 

 whether any individual bee ever re- 

 covers from an attack of disease. Many 

 bee-keepers think that adult bees in 

 American foul brood colonies are less 

 active than in normal colonies. 

 Whether they suffer from disease, we 

 do not know. It is possible, but not 

 probable, that they have suffered a 

 light attack of disease while in the 

 development stage and emerged as 

 adult bees with weakened organs 

 which do not perform a normal func- 

 tion. If this were true, it would illus- 

 trate the importance of preexisting 

 disease as a predisposing factor in 

 etiology. 



Having thus briefly considered some 

 of the more important predisposing 

 causes which enter into the etiology 

 of bee diseases, let us consider two of 

 the 'more important exciting causes, 

 food and microorganism. 



Exciting Causes. 



Food. — The character of food is be- 

 lieved by many bee-keepers to be an 

 exciting factor in dysentery. Should 

 the food contain poisons, grave results 

 might follow. Some attribute paral- 

 ysis to the character of the food but 

 this is far from a demonstrated fact. 



IVIicroorganisms. — ^By microorganisms 

 we mean those living plants and ani- 

 mals which are very small and must be 

 magnified greatly before they can be 

 seen. Those which are to receive our 

 attention are bacteria, protozoa, and 

 " fungi. 



Bacteria. — We have now come to the 

 consideration of that factor in the 

 etiology of bee diseases which is imost 

 important and with which we would 

 have the bee-keepers familiar. The 

 annual loss sustained by the bee- 

 keepers of this country, due to the one 

 cause, bacteria, is to be reckoned in 

 millions. It is unfortunate that it is 

 necessary to use the word bacteria be- 

 cause too many at once think that they 

 are not able to understand anything 

 about bacteria. This is a mistaken 

 idea. It is not difficult to understand 



the facts about them which are most 

 important in the treatment of disease. 

 It might be well to review here some of 

 the things about their life history. 



Nearly two years ago, I had the 

 honor and pleasure of, reading a paper 

 at a meeting of bee inspectors, held 

 at San Antonio, Texas, upon the sub- 

 ject of the bacteriology of bee dis- 

 eases. This paper you can find in 

 Bulletin No. -70 of the Bureau of En- ' 

 tomology, of the United States De- 

 partment of Agriculture, on page 10. 

 In it is discussed briefly the nature of 

 bacteria, their distribution, the meth- 

 ods of their study, and the results of 

 their activity. In the paper you are 

 told that bacteria, often called germs, 

 microbes and parasites, are very small 

 plants. So small, indeed, that 12,000 

 placed end to end measure but one 

 inch. They increase in number with 

 marvelous rapidity. Under favorable 

 conditions each bacterium in twenty 

 rhinutes becomes two. At this rate 

 countless millions are formed in 

 twenty-four hours. As the soil be- 

 comes exhausted in which they are 

 growing, many species form spores 

 which are in a way comparable to the 

 seed of higher plants. These spores 

 are very difficult to destroy by heat 

 and other disinfectants. It is well to 

 remember, concerning the distribution 

 of bacteria, that they are found in 

 very large numbers everywhere about 

 us but that most of them are as harm- 

 less as the vegetables we eat. But 

 should there be introduced into an 

 apiary, for example, species of bac- 

 teria which cause American foul 

 brood, then the brood becomes ex- 

 posed to the disease and will probably 

 contract it. 



The study of bacteria must be done 

 for the most part in the laboratory. 

 By the use of the microscope, we are 

 able to tell the genus (e. g. bacillus) 

 to which an organism belongs, and by 

 specially prepared media or soil, we 

 are able to determine the species to 

 which it belongs (e. g. alvei.) 



Having determined these things 

 about bacteria, we are interested in 

 finding out what they are capable of 

 doing. We learn that some do good, 

 for example, the bringing to decay the 

 remains of dead animals and plants, 

 while other species do harm by their 

 ability to produce disease or death in 

 the animals in which they are able to- 

 gain entrance. The disease, American 



