Submitted to: Developments in Biologicals
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 19, 2012
Publication Date: May 1, 2013
Citation: Afonso, C.L., Miller, P.J. 2013. Newcastle Disease: Progress and gaps in the development of vaccines and diagnostic tools. Developments in Biologicals. 135:95-106. Interpretive Summary: Genetically diverse virulent Newcastle disease viruses circulate and cause Newcastle Disease in poultry in different countries worldwide. There are huge reservoirs of the virus in neighboring countries or in countries with extensive commercial trade with the U.S. Virulent viruses also exist in wild birds in the U.S. The possibility of the introduction of virulent viruses in U.S. poultry could have serious impacts on production and in the trade of poultry and poultry products. There are significant gaps of knowledge in diagnostics and in vaccination that need to be addressed by research and need to validate existing diagnostic tests. These gaps are highlighted in this review.
Technical Abstract: Newcastle disease (ND) is a contagious disease of birds that can have severe economic consequences for any poultry producer, including a serious impact on the international trade of poultry and eggs. Newcastle disease virus (NDV) isolates are also called avian paramyxovirus serotype-1 isolates, but only infection with virulent NDV (vNDV) causes the disease. Virulent Newcastle disease virus (vNDV) isolates are distributed worldwide and have a high capacity to mutate, allowing the development of multiple NDV genotypes evolving simultaneously at different locations. Large gaps of knowledge existing in the areas of epidemiology and evolution limit the control of the disease. Recurrent infection of poultry and wild birds allows the maintenance of a reservoir for the viruses; however, the role of wild birds and poultry in NDV evolution is barely known. In the area of diagnostics, the performance of fast and accurate diagnostics methods is often affected by the evolving genomes of the viruses. Therefore, there is a need for the validation of multiple recently developed experimental tests and a need to develop additional fast low cost diagnostics reagents to be used as field. In the area of vaccination, the development of low-cost thermostable NDV vaccine and the development of vaccines capable of preventing viral replication are highest priorities for endemic countries. In countries considered free of vNDV the development of low-cost vaccines that produce minimal vaccine reactions to prevent decreased productivity are higher priorities. Worldwide, better strategies that replace culling of infected birds are needed to control outbreaks