Detection and quantitation of equid gammaherpesviruses (EHV-2, EHV-5) in nasal swabs using an accredited standardised quantitative PCR method

J Virol Methods. 2014 Mar:198:18-25. doi: 10.1016/j.jviromet.2013.12.008. Epub 2013 Dec 24.

Abstract

Equid gammaherpesviruses-2 and -5 are involved in respiratory problems, with potential clinical manifestations such as nasal discharge, pharyngitis and swollen lymph nodes. These viruses are sometimes associated with a poor-performance syndrome, which may result in a significant and negative economic impact for the horse industry. The aim of the present study was to develop and validate quantitative PCR methods for the detection and quantitation of EHV-2 and EHV-5 in equine respiratory fluids. Two distinct tests were characterised: (a) for the qPCR alone and (b) for the whole method (extraction and qPCR) according to the standard model AFNOR XP U47-600-2 (viz., specificity, quantifiable sensibility, linearity, accuracy, range of application, trueness, precision, repeatability and precision of reproducibility). EHV-2 and EHV-5 detection were performed on nasal swabs collected from 172 horses, all of which exhibited clinical signs of respiratory disease. The data revealed a high rate of EHV-2/EHV-5 co-detection that was correlated significantly with age. Viral load of EHV-2 was significantly higher in young horses whereas viral load of EHV-5 was not significantly different with age.

Keywords: Accredited standardised method; EHV-2; EHV-5; Horses; qPCR.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Gammaherpesvirinae / genetics*
  • Herpesviridae Infections / virology*
  • Horse Diseases / virology
  • Horses / virology*
  • Nose / virology*
  • Polymerase Chain Reaction / methods*
  • Reproducibility of Results
  • Respiratory Tract Diseases / virology*
  • Viral Load / genetics