Download Avian paramyxovirus type 1 in hens' hatching eggs - Import risk analysis (March 2001)

This document is an analysis of the risk posed by exotic strains of avian paramyxovirus type 1 (the causative agent of Newcastle disease) in imported hatching eggs of hens (Gallus gallus). Although non-pathogenic strains of avian paramyxovirus type 1 are present in New Zealand, there has never been an outbreak of Newcastle disease in this country.
This analysis concludes that there is a low risk that exotic strains of avian paramyxovirus type 1 could be introduced in hen's hatching eggs. The spread of introduced strains is considered possible by a variety of exposure pathways, although the risks of airborne spread have been greatly exaggerated over the past 30 years. The introduction of highly virulent strains of the virus would almost certainly result in serious mortality in commercial and hobby poultry flocks. Furthermore, exposure of wild birds could lead to the virus being introduced into endangered native bird populations, with potentially devastating effects. While the introduction of field strains of low virulence might not cause severe disease in New Zealand bird populations, some strains may have significant effects on avian health and production, and since low virulence field strains may not be as stable as was thought in the past, there is a possibility that such strains could mutate to become virulent after introduction into chicken flocks.
Recommendations for importations of hatching eggs were made and for the review of the current avian quarantine facility standard, which includes safeguards for airborne spread.