142 SPECIAL EQUINE THEEAPY 



ease. Most commonly, however, influenza in equine pa- 

 tients runs an irregular course, involving various organs 

 and tissues in uncertain degree. 



In my opinion a typical ease of influenza limits its 

 manifestations to pathologic changes in mucous mem- 

 branes. Whenever the case presents symptoms denoting 

 involvement of an organic nature in other tissues, I be- 

 lieve it is atypical and due to a mixed infection. Infec- 

 tion with the virus of influenza gives, in my opinion, a 

 typical attack of influenza characterized by high fever, 

 depression, anorexia and catarrhal inflammation of mu- 

 cous membranes. The addition of pus producing micro- 

 organisms — ^various strepto- and staphylococci — making 

 a mixed infection, gives us what are usually termed com- 

 plications : in other words, atypical cases. This opinion 

 is in great part substantiated by a fact with which many 

 practitioners are well acquainted, namely, that many 

 times these complications are more violent than the true 

 influenza symptoms, and frequently manifest themselves 

 when the symptoms of influenza proper are already under 

 control. 



A division of influenza infections into catarrhal and 

 pneumonic or pectoral sets, is not rational. A division 

 can only be made on the basis of typical and atypical 

 manifestations, classing all eases with symptoms that 

 deviate from those of an acute, catarrhal inflamma- 

 tion, and its recognized phenomena, as atypical. Thus 

 we may have a typical enteric influenza or a typical 

 pectoral influenza, or a typical influenza infection of 

 any other organ or tissue. But the course of the 

 infection in any organ or tissue can only be typical 

 when the pathological invasion is true to type; that is, 

 when the infection is not a mixed infection. Just as soon 

 as the virus of influenza is reinforced by staphylo- or 

 streptococcus infection in an organ or tissue, symptoms 



