Agglutination of red blood cells of different animal species by influenza and Newcastle disease viruses

Abstract

The agglutination of red cells of seventeen animal species by influenza and Newcastle disease viruses has been quantitatively investigated. The peculiar behaviour of one group of red cells, illustrated by ox, toward influenza virus heated for 30 min. at 56° C. and toward purified N.D.V. has been studied in detail. It is concluded that heated influenza virus acquires an apparently increased titre against ox cells because it has lost its eluting power. Similarly, purified N.D.V. is less readily eluted from red cells, due to the elimination of an ‘elution-hastening factor’ present in infected fluid. The present study illustrates the importance of careful adjustment of all possible variable conditions for individual viruses and individual red cell systems.