Submitted to: United States Animal Health Association Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 11/5/2001
Publication Date: 2/28/2002
Technical Abstract: Changes in the definition of reportable ND, those outbreaks that may impact international trade, have evolved following improved control of virulent Newcastle disease virus (NDV) infections and recent events that have extended the definition of viruses that are a risk to poultry. The U. S. Code and the OIE definition of Newcastle disease (ND) were essentially the same until the new Office International des Epizootes (OIE) definition was approved in 1999. The U.S. Code still defines Exotic ND as an acute and usually fatal viral disease of birds and poultry. In contrast the OIE now defines ND as an infection of birds by a virus of avian paramyxovirus type 1 (APMV-1, synonymous with NDV) that meets one of two test criteria for virulence. Both the terminology and criteria differ. Reportable ND, by either definition, is not present in poultry in the U. S., but infections with low virulence NDV strains are present and diagnosticians have in the past reported these low virulence NDV infections as ND. If diagnosticians continue to report the low virulence infections as ND, this may lead to misinterpretation of disease reports by importing countries and provide the false impression that virulent disease is present in the U.S. It is suggested to avoid misinterpretation that these low virulence infections be reported as APMV-1 infections or as NDV, low virulence or lentogenic type.