120 



Scientific Proceedings (99). 



67 (1442). 



The results of the use of absorption of agglutinin on the identi- 

 fication of strains of influenza bacilli. 



By William H. Park, Anna W. Williams, and 

 Georgia Cooper. 



[From the Department of Health of the City of New York.] 



The fact that Dr. Williams obtained abundant influenza 

 bacilli in the pharynx of nearly all cases of influenza and that in 

 the lungs of fatal cases she found them in pure cultures in about 

 20 per cent, of those taken, together with the similar results ob- 

 tained in Boston and in some of the camps, strongly suggested 

 the possibility that the influenza bacillus might be the causative 

 agent in the epidemic. It seemed to us apparent that the differ- 

 ent influenza bacilli from the different cases should necessarily be- 

 long to the same type if the influenza bacillus were the cause of 

 the epidemic. We obtained, therefore, in pure culture strains 

 from over 100 cases, and of these injected 20 individually into dif- 

 ferent rabbits. All of these strains produced a good quantity of 

 agglutinin. In testing the strains with these twenty individual 

 sera, we found the surprising fact that only four of the serums 

 agglutinated any other strains beyond the ones used to immunize 

 the rabbits. The technic of those doing this work was tested 

 in every conceivable way without changing the results. Cultures 

 were also passed through animals and grown on different media 

 without altering these strains from the agglutination standpoint. 



One of the investigators by accident received some of a fresh 

 influenza culture into her throat. In forty-eight hours she de- 

 veloped an attack of bronchitis. The influenza bacilli found were 

 identical in strain with those which were received from the cul- 

 ture. This holding of the strain characteristics in the secondary 

 case is evidence that the strain does not quickly change. This 

 evidence of multiple strains seems to us to be absolutely against 

 the influenza bacilli isolated being the cause of the pandemic. It 

 appears to us impossible that we should miss the epidemic strain 

 in so many cases, while obtaining some other strain so abundantly. 

 The influenza bacilli, like the streptococci and pneumococci, are 

 in all probability merely very important secondary invaders. 



