THE THERAPEUTIC EFFICIENCY OF AVIAN DIPHTHERIA, 

 ROUP, AND BIRD POX VACCINES AND BACTERINS 



Bv NORMAN J. PYLE 



Introijuctiox 



Avian diphtheria, roup, and bird pox have caused serious financial losses 

 to the poultry industry of Massachusetts during the fall and winter months 

 of past years. Diphtheritic roup has been the predominating form of the dis- 

 ease. It has not been attended with great mortality, but has become of grave 

 economic importance because it has caused a decrease in production, occurring 

 at a time of the year when poultry products bring maximum prices. 



Two biological products, a powdered pox virus vaccine and an avian mixed 

 infection bacterin, have been used extensively in an attempt to control the 

 disease. The results obtained following the use of the preparations have been 

 confusing. Some reports claim the vaccine to be 100 per cent efficient, while 

 others claim it to be an absolute failure. 



Many factors contribute towards the efficiency of the vaccine and bacterin. 

 It is of primary importance to ascertain the nature of the causative micro- 

 organism or virus and whether it is incorporated in either of the preparations. 

 When this is accomplished, it is assured that either the vaccine or bacterin is 

 the logical product to develop specific antibodies against the disease. 



It is also necessary to determine whether avian diphtheria, roup, and bird 

 pox are separate etiological entities or various manifestations of a common 

 cause. On the answer to this problem depends the need for one common 

 vaccine or bacterin or for separate ones for each entity. 



Historical. 



Moore (1), a pioneer American worker on avian diphtheria and roup, iso- 

 lated a non-motile, pathogenic bacillus from lesions of the disease. He claimed 

 that this organism was "apparently the etiological factor". He was unable, 

 however, to determine its specificity for the affection. Harrison and Streit 

 (2) demonstrated that Bacillus pijocyanens would produce typical lesions of 

 avian diphtheria and roup. These authors also found a second virulent bac- 

 terium associated with the diseases, which they called the roup bacillus or 

 B. cacosmos. Hausser (3), Bordet and Fally (4), Beach, Lothe and Halpin 

 (5), and Crofton (6) have all added specific organisms to the long list of 

 causative factors. 



Bird pox or contagious epithelioma has not been studied from the stand- 

 point of its etiology to the extent that has avian diphtheria. Marx and Sticker 

 (7) reported investigations wherein they found ai filtrable virus to be the 

 cause of bird pox. Schmid (8) and Sigwart (9) confirmed this work. 

 V. Betegh (10), De Blieck and V. Heelsbergen (11), and others advanced the 

 theory that all forms of the disease are caused by one and the same virus. 



Several references in the early literature maintain that the various poxes, 

 skin eruptions, and variola affecting animal life are all caused by a common 

 virus, which adapts itself over a period of successive generations to a specific 

 host. If this were true, vaccinia or cowpox would have an etiological rela- 

 tionship to bird pox. 



