Serological relationships between certain avian and animal paramyxoviruses

An avian paramyxovirus designated Robin/Hiddensee/19/75 proved to be related to the Yucaipa virus group in cross haemagglutination inhibition test (HIT). Whereas the prototype parainfluenza viruses did not react with the antiserum raised against the Robin virus, a newly isolated bovine parainfluenza 3 virus was shown to be inhibited up to half the homologous titre. Possible antigenic relationships between avian, mammalian and human paramyxoviruses are discussed.