110 VACCINE AND SERUM THERAPY 



mucous membrane, of the foetal membranes and the 

 foetus itself. 



According to the work done in recent years, the 

 term abortion, as indicating a specific distinctive 

 disease, is misleading. Abortion is not a disease, but 

 one of the symptoms of a variety of diseases caused 

 by a variety of infections. 



Etiology. — Since the discovery by Bang of a short 

 bacillus, which he called the B. abortus, and which 

 he claimed to be the cause of abortion, this disease 

 has been everywhere considered to be the result of 

 infection by the B. ahortits. Recently, however, 

 dissension has arisen among workers upon this 

 disease as to the specificity of B. abortus in producing 

 the lesions responsible for abortion. Notably among 

 the workers who disclaim this specificity are such 

 authorities as Professor Williams and numerous other 

 well-known clinicians in America, and most Danish 

 authorities now hold this later view. From clinical 

 experience I am in accord with the non-specific theory 

 of contagious abortion. 



The commonest organisms which are found to be 

 associated with lesions responsible for abortion are — 



1. B. abortus, 



2. Streptococci. 



3. Colon bacilli. 



4. Vibrios. 



5. Spirilla. 



6. B. ijyocyaneus. 



Immunisation. — The method of immunisation re- 



