WorldPoultry: Wild birds an unlikely source of Newcastle disease

Wild ducks and shorebirds do not appear to carry Newcastle disease viruses that sicken or kill poultry, according to a new study led by the US Geological Survey.

Avian paramyxovirus viruses, which can cause Newcastle disease, are found throughout the planet, infect wild and domestic birds, and sometimes lead to disease outbreaks. In North America, previous research found that paramyxoviruses in cormorants, have occasionally been associated with bird mortality events. However, few studies have assessed virus exchange among wild waterbirds and across the landscape.

Costly poultry pathogen
“Newcastle disease has been associated with outbreaks of disease in pet and zoo birds and is among the most economically costly poultry pathogens worldwide,” said Andy Ramey with USGS and lead author of the study. “However, there hasn’t been a tremendous amount of research focusing on how viruses are spread among different types of wild waterbirds or within North America.”

USGS and collaborators from US Southeast Poultry Research Laboratory of the US Department of Agriculture, the University of Texas and the University of Georgia examined the genetic relationships of avian paramyxoviruses isolated from wild bird samples from across the US to examine the evidence for exchange of viruses among different types of birds such as cormorants, ducks, shorebirds, and gulls. The authors also examined how viruses are dispersed across the continent. 

Genetic diversity
“We found new genetic diversity in these wild bird samples but nothing that suggests that ducks or shorebirds are a reservoir for viruses causing Newcastle disease or strains that are likely to be harmful to domestic poultry,” said Ramey. The authors also found that some genetic diversity of avian paramyxoviruses appears to be widespread among different species and geographic locations whereas other viruses may be limited to certain regions or particular hosts.

The new report is entitled, “Assessment of contemporary genetic diversity and inter-taxa/inter-region exchange of avian paramyxovirus serotype 1 in wild birds sampled in North America” and is available at the website for Virology Journal.