Antigenic heterogeneity amongst the field isolates of Newcastle disease virus (NDV) in relation to the vaccine strain. Part II: Studies on viruses isolated from domestic birds in Israel

Abstract In order to reveal the viruses strongly differing from the VH NDV strain used in Israel for poultry vaccination, 54 NDV strains isolated during the last 15years in Israel from feral birds were studied by means of the panels of 39 monoclonal antibodies. Six isolates were found to have considerable antigenic differences in envelope proteins as compared to the vaccine strain. In four cases, the differences were related mostly to the hemagglutinin-neuraminidase glycoprotein, in one case to the fusion glycoprotein, and in one case to the matrix protein.