%0 Journal Article %T Avian Paramyxovirus Serotype-1: A Review of Disease Distribution, Clinical Symptoms, and Laboratory Diagnostics %A Nichole L. Hines %A Cathy L. Miller %J Veterinary Medicine International %D 2012 %I Hindawi Publishing Corporation %R 10.1155/2012/708216 %X Avian paramyxovirus serotype-1 (APMV-1) is capable of infecting a wide range of avian species leading to a broad range of clinical symptoms. Ease of transmission has allowed the virus to spread worldwide with varying degrees of virulence depending on the virus strain and host species. Classification systems have been designed to group isolates based on their genetic composition. The genetic composition of the fusion gene cleavage site plays an important role in virulence. Presence of multiple basic amino acids at the cleavage site allows enzymatic cleavage of the fusion protein enabling virulent viruses to spread systemically. Diagnostic tests, including virus isolation, real-time reverse-transcription PCR, and sequencing, are used to characterize the virus and identify virulent strains. Genetic diversity within APMV-1 demonstrates the need for continual monitoring for changes that may arise requiring modifications to the molecular assays to maintain their usefulness for diagnostic testing. 1. Introduction Avian paramyxovirus serotype-1 (APMV-1) is a member of the Paramyxoviridae family and is the causative agent of virulent Newcastle disease (vND). The virus is able to infect all orders of avian species, and virulent strains can cause significant clinical signs. Due to the extensive range of susceptible hosts, the virus has been able to establish itself worldwide. Infection by virulent strains has resulted in several panzootics since 1926 [1¨C3]. This disease can have devastating effects on the poultry industry due to the high morbidity and mortality associated with virulent strains of the virus [4¨C6]. Clinical signs of vND include drop in egg production, respiratory distress, listlessness, weakness, and central nervous system symptoms [2]. Vaccination programs exist within the United States (US), but the virus continues to replicate upon infection and can spread from infected vaccinated flocks. Currently the US is free of vND, but introduction of the disease continues to be a major concern for the agricultural community [2]. Illegal importation of infected birds is one of the major modes of vND introduction into the US. Diagnostic testing and rapid detection are important steps to prevent an outbreak of the disease. Real-time reverse transcription polymerase chain reaction (rRT-PCR) is a rapid diagnostic test for detection of APMV-1 RNA. Virus isolation in embryonating chicken eggs is the ˇ°gold standardˇ± method of virus identification but can require 5 to 10 days to obtain an isolate. The current United States Department of Agriculture- (USDA-) %U http://www.hindawi.com/journals/vmi/2012/708216/