%0 Journal Article %A Donald, Heather B. %A Isaacs, A. %T Some Properties of Influenza Virus Filaments shown by Electron Microscopic Particle Counts %D 1954 %J Microbiology, %V 11 %N 2 %P 325-331 %@ 1465-2080 %R https://doi.org/10.1099/00221287-11-2-325 %I Microbiology Society, %X SUMMARY: A strain of influenza virus A which produced abundant filaments was more efficient in agglutinating red cells than non-filamentous strains. This was shown by counts of the number of particles (i.e. filaments and spheres)/agglutinating dose; the ratios found were 106·6 for the filamentous, and 107·2 for the non-filamentous strains. The increased efficiency of agglutination was shown by filtration experiments to be due to the filaments. There was no corresponding increase in the efficiency of initiating infection. Treatment of a filamentous preparation with ultrasonic vibrations caused breakdown of the filaments, an increase in agglutination titre but no change in the infectivity titre. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-11-2-325