Abstract:
Newcastle disease (ND) is considered as a highly infectious disease of poultry worldwide. The
commercial broiler industry is highly susceptible to virulent NDV, the data indicating heavy
losses and documentary proof is available on NDV surveillance program. However, a little is
known regarding the maintenance and enzootic trends of vNDV infection level in domestic and
wild birds. Poor vaccination strategy as well as the existence of virulent form of NDV in the
domestic birds indicates a root cause of the occurrence of disease eruption in the developing
countries. Here, we report the eleven complete genome sequences of NDV from lovebird parrot
(n=1) and exotic parakeets (n=3), backyard chickens (n=5), peacock (n=1) and pheasant (n=1).
The complete genome lengths of all isolates were 15,192 nucleotides (nt) with same virulenceassociated
cleavage site (112-RRQKRF-117) and selected ones have intracerebral pathogenicity
index (ICPI) values ranging from 1.50 to 1.86, which is typical of vNDV. The deduced amino
acid residues analyses have shown a number of substitution mutations in the functional domains
of fusion and hemagglutinin-neuraminidase proteins. Phylogenetic analysis showed all NDV
isolates belong to sub-genotypes VIIi within the genotype VII of class II. The isolation of highly
similar viruses (98-99%) during 2011-16 provides the evidence of an epidemiological links
between poultry, domestic and wild birds. Our results also support the existence of fifth
panzootic as these viruses primarily isolated from South Asia, Middle East and Indonesia and
recently spread into Eastern Europe. Active surveillance of these newly emerging viruses to
determine their evolution is one of the most realistic strategies for preventing and controlling
NDV outbreaks.
