Newcastle disease outbreaks in the Sudan from 2003 to 2006 were caused by viruses of genotype 5d

Newcastle disease (ND) is a serious neurological and respiratory disease of poultry that affects all types of birds but has traditionally not caused symptoms in wild aquatic birds, the natural hosts. In the late 1990s, a new genotype, viz. 5d that is pathogenic to all types of birds, including waterfowl, arose in China and has since spread from East Asia into parts of Europe, the Middle East and Africa. We performed a phylogenetic analysis of the fusion protein gene of isolates obtained from outbreaks of ND in Sudan and found that all contemporary strains isolated between 2003 and 2006 were of genotype 5d, containing the virulent fusion protein cleavage site (F0) motif (112)RRQKRF(117). Introduction via a Middle Eastern trade partner is likely to be the source of infection since phylogenetic analysis excluded the possibility of introduction from western and southern Africa.