Newcastle disease virus (NDV), is a variant of avian paramyxovirus 1 (APMV-1), a negative-sense, single-stranded RNA virus. NDV/APMV-1 belong to the genus Avulavirus in the family Paramyxoviridae. Transmission occurs by exposure to faecal and other excretions from infected birds, and through contact with contaminated food, water, equipment, and clothing.