Comparison of Nested and Real-Time PCR for Detection of Latent Equine Herpesvirus 1 Infection

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  • Himanshu Sharma Lala Lajpat Rai University of Veterinary and Animal, Hisar, Haryana, India
  • Sanjay Kapoor Lala Lajpat Rai University of Veterinary and Animal, Hisar, Haryana, India
  • Baldev Raj Gulati ICAR-National Research Centre on Equines, Hisar, Haryana, India


Equine herpesvirus 1, latency, PCR, real-time PCR, sensitivity


Equine herpesvirus 1 (EHV1) is one of the most important equine viral pathogen. Following acute infection, recovered animals develop lifelong latent infection, with periodic reactivation. The objective of this study was to compare nested and real-time PCR targeting glycoprotein B (gB) gene for detection of latent EHV1 infection. The real-time PCR (gB-qPCR) assays detected 41 gene copies/ reaction while nested PCR (gB-nPCR) assays could detect 4100 gene copies/ reaction. For assessing diagnostic sensitivity of both the assays, an abortion outbreak was followed for 6 months. After 6 months, none of the aborting (24) mares was shedding virus in nasal and vaginal swabs. However, latent EHV1 infection was detected in 7 and 15 mares by nested and real-time PCR respectively, by demonstration of viral DNA in peripheral blood mono-nuclear cells (PBMCs) in the absence of detectable late structural gene mRNA using gB-based real-time PCR. The sensitivity of gB-nPCR was only 46.66% as compared to gB-qPCR for detection of EHV1 latent infection. The real-time PCR is a sensitive and specific assay for ante-mortem detection of EHV1 latency in equine population.

Author Biography

  • Baldev Raj Gulati, ICAR-National Research Centre on Equines, Hisar, Haryana, India

    Principal Scientist, Equine Health Unit

    ICAR-National Research Centre on Equnies, Hisar


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How to Cite

Comparison of Nested and Real-Time PCR for Detection of Latent Equine Herpesvirus 1 Infection. (2019). ISVIB Journal Veterinary Immunology & Biotechnology, 1(2).