Studies on the Structural Basis of the RNA Polymerase Activity of Newcastle Disease Virus Particles

Abstract

A quantitative immunofluorescent cell-counting technique was used to investigate the virustatic effect of aminoadamantane, ammonium acetate and a number of aliphatic amines on the development of influenza virus antigens in BHK-21 cell monolayers. Influenza virus strains A2/scotland/49/57, A/nws and B/england/939/59 were used at high multiplicities of infection in the tests. Quantification of the activity of the antiviral compounds was provided by the direct estimation of the proportion of infected cells in which the production of influenza virus fluorescent antigens was blocked. Comparable results were obtained for A2/scotland/49/57 virus using the immunofluorescent technique and the more conventional method of measuring antiviral activity by the reduction in the ability of the virus to multiply in tissue culture in the presence of the test compounds.