Equine Influenza PCR Assay Available in Kentucky

The Livestock Disease Diagnostic Center (LDDC) at the University of Kentucky now offers a molecular diagnostic assay to detect the H3N8 equine influenza virus (also known as type 2 equine influenza virus) in clinical specimens. Currently only the H3N8 subtype is associated with equine influenza virus outbreaks around the world.

This new assay is the most sensitive method to detect this respiratory viral pathogen. The assay is based on real-time RT-PCR (reverse transcription-polymerase chain reaction) technology, which is highly sensitive and specific for the detection of H3N8 influenza virus. The assay was recently developed and validated at UK's Maxwell H. Gluck Equine Research Center and published in the Journal of Clinical Microbiology.

"(Real-time RT-PCR) is a laboratory technique based on polymerase chain reaction to detect viral nucleic acids (specifically viruses with RNA genomes like equine influenza) in clinical specimens. Use of real-time RT-PCR assays has significantly improved the diagnosis of infectious diseases," said Udeni Balasuriya, BVSc, MS, PhD, of the Gluck Center.

Equine influenza is an acute, highly contagious viral respiratory disease of equids (horses, donkeys, mules, and zebras) caused by infection with type A influenza virus. Equine H3N8 influenza virus spreads rapidly in susceptible horses and can result in high morbidity (illness) within 24-48 hours after the horse is exposed. A provisional diagnosis of equine influenza must be confirmed by laboratory testing. Furthermore, the need to achieve a rapid diagnosis to implement effective quarantine and movement restrictions is important to prevent spread of equine influenza.

The diagnosis of equine influenza was traditionally attempted by virus isolation from clinical samples in chicken eggs or by detection of viral antigen by immunoassays. The recommended specimen type is the nasal swab submerged in a viral transport medium that is then packed in ice. There are special equine nasal swab sampling kits available from the Gluck Center (see contacts below).

The cost of the new equine influenza test per animal is $35 for in-state and $52.50 for out-of-state submissions. Tests will be set up Monday through Friday.

For more information contact molecular biologist Steve Sells (stephen.sells@uky.edu) or Craig Carter, DVM, PhD, (craig.carter@uky.edu) at the LDDC, or Balasuriya (ubalasuriya@uky.edu) at the Gluck Center.

Alexandra Harper is a UK equine communications intern and undergraduate majoring in communications.

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More information on Gluck Equine Research Center, and UK's Equine Initiative.

Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.