Location: Exotic & Emerging Avian Viral Diseases Research
Title: Improved real-time RT-PCR tests for class II Newcastle disease virusesAuthor
Suarez, David | |
FERREIRA, HELENA - Orise Fellow |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 3/15/2018 Publication Date: 7/13/2018 Citation: Suarez, D.L., Ferreira, H.L. 2018. Improved real-time RT-PCR tests for class II Newcastle disease viruses[abstract]. American Veterinary Medical Association Annual Meeting, July, 13-16, 2018, Denver, Colorado. CDROM. Interpretive Summary: Technical Abstract: Virulent Newcastle disease virus (NDV) is an exotic animal disease in the United States, but it is endemic in a large part of the world and creates a risk for introduction into the U.S. The rapid diagnosis of the virus through the National Animal Health Laboratory Network by a real-time RT-PCR test allows for a timely control effort to mitigate a future introduction. The current NDV is based on primers targeted to the matrix gene for Class II viruses, and it remains a sensitive and specific test for many lineages of the virus. Unfortunately because of the genetic diversity of NDV, some genotypes of virus may be missed or have greatly reduced sensitivity. A fresh approach to develop new real-time RT-PCR tests, capitalizing on the large NDV sequence database for class II NDV isolates, was performed that analyzed the entire genome of hundreds of isolates to identify highly conserved regions. Using a single nucleotide polymorphism (SNP) analysis, multiple different primer sets were identified and empirically tested. Three different primers sets, 1 in the nucleoprotein and 2 in the polymerase gene were selected that had high sensitivity and specificity. Bioinformatically all three tests were more conserved than the matrix test and were able to identify more isolates than the matrix test with similar sensitivity. The availability of alternative bench validated primer sets for Newcastle disease virus provides viable alternatives if the current test does not perform as expected. |