Detection and quantification of equine herpesvirus-1 viremia and nasal shedding by real-time polymerase chain reaction

Stephen B. Hussey, Rodney Clarke, Katharine F. Lunn, Cormac Breathnack, Gisela Soboll, J. Millar Whalley, D. Paul Lunn

    Research output: Contribution to journalArticlepeer-review

    71 Citations (Scopus)


    Equine herpesvirus-1 (EHV-1) infection is common in young horses throughout the world, resulting in respiratory disease, epidemic abortion, sporadic myelitis, or latent infections. To improve on conventional diagnostic tests for EHV-1, a real-time polymerase chain reaction (PCR) technique was developed, using primers and probes specific for the EHV-1 gB gene. Amplification efficiencies of 100% +/- 5% were obtained for DNA isolated from a plasmid, infected peripheral blood mononuclear cells (PBMCs), and nasal secretions from infected ponies. The dynamic range of the assay was 8 log10 dilutions, and the lower limit of detection was 6 DNA copies. Fifteen ponies, seronegative for EHV-1, were experimentally infected with EHV-1, and nasal samples were used to quantify shedding of virus by both virus isolation and real-time PCR analysis. Virus isolation identified nasal shedding of EHV-1 in 12/15 ponies on a total of 25 days; real-time PCR detected viral shedding in 15/15 ponies on 75 days. Viremia was quantified using PBMC DNA, subsequent to challenge infection in 3 additional ponies. Viremia was identified in 1/3 ponies on a single day by virus isolation; real-time PCR detected viremia in 3/3 ponies on 17 days. When real-time PCR was used to analyze PBMC DNA from 11 latently infected ponies (documented by nested PCR), EHV-1 was not detected. We conclude that real-time PCR is a sensitive and quantitative test for EHV-1 nasal shedding and viremia and provides a valuable tool for EHV-1 surveillance, diagnosis of clinical disease, and investigation of vaccine efficacy.
    Original languageEnglish
    Pages (from-to)335-342
    Number of pages8
    JournalJournal of Veterinary Diagnostic Investigation
    Issue number4
    Publication statusPublished - 2006


    • diagnosis
    • equine herpesvirus-1
    • real-time PCR


    Dive into the research topics of 'Detection and quantification of equine herpesvirus-1 viremia and nasal shedding by real-time polymerase chain reaction'. Together they form a unique fingerprint.

    Cite this