Consensus PCR protocols for the detection of amphibian herpesviruses (Batrachovirus)

J Vet Diagn Invest. 2020 Nov;32(6):864-872. doi: 10.1177/1040638720951134. Epub 2020 Aug 28.

Abstract

Amphibians have been disappearing at an unprecedented rate worldwide. Among the proposed contributing factors are infectious diseases. Investigations have focused mainly on ranavirus and chytrids; however, additional agents may be relevant stressors. Two novel batrachoviruses have been discovered (ranid herpesvirus 3 [RaHV-3] and bufonid herpesvirus 1 [BfHV-1]). Their clinical role is still to be clarified; however, both have been associated with obvious skin lesions in their respective hosts. Herein we present 2 consensus PCR protocols that can be used to detect all of the known and, possibly, yet to be discovered batrachoviruses. We targeted a 200 nt long, highly conserved region of the DNA terminase gene. We established a sensitive protocol, which can detect both European batrachoviruses (European batrachovirus PCR protocol; RaHV-3 and BfHV-1) and a panbatrachovirus PCR protocol detecting all known batrachoviruses, including ranid herpesvirus 1 and 2 (RaHV-1, -2). The limit of detection (LOD) for the European batrachovirus protocol was 101 copies of RaHV-3 and 102 copies of BfHV-1 per reaction. The panbatrachovirus protocol could detect all known batrachoviruses with LODs of 103 (RaHV-3, BfHV-1, RaHV-1) to 104 copies (RaHV-2) per reaction. These novel detection tools can be used as a first line of detection when herpesviral infection in amphibians is suspected, followed by additional PCRs with herpesvirus-specific primers in the case of known viral species, or sequencing as in the case of novel batrachoviruses.

Keywords: Alloherpesviridae; Batrachovirus; PCR; amphibian; frogs; herpesvirus; toads; wildlife.

MeSH terms

  • Amphibians / virology*
  • Animals
  • Consensus*
  • DNA Primers
  • Herpesviridae / classification*
  • Herpesviridae / genetics*
  • Herpesviridae / isolation & purification
  • Herpesviridae Infections / veterinary*
  • Polymerase Chain Reaction / methods
  • Polymerase Chain Reaction / veterinary*

Substances

  • DNA Primers