Detection and characterisation of multiple herpesviruses in free-living Western European hedgehogs (Erinaceus europaeus)

Helle B Hydeskov,Becki Lawson,Akbar Dastjerdi,Kevin P Hopkins,Marie-Pierre Ryser-Degiorgis,Frederik Widén,Andrew A Cunningham

doi:10.1038/s41598-018-31900-w

Abstract

Sporadic cases of herpesvirus-associated disease have been reported in the Western European hedgehog (Erinaceus europaeus), but there has been little surveillance for, nor any sequence characterisation of, herpesviruses in this species to date. A nested pan-herpesvirus polymerase chain reaction (PCR) targeting a region of the DNA polymerase gene was used to test 129 Western European hedgehogs from across Great Britain, 2011–2016; 59 (46%) of which were PCR-positive. In addition, samples from two previously published cases of fatal herpesvirus infection in E. europaeus, from Sweden and Switzerland, were positive using this PCR. No statistically significant relationship was detected between PCR result and sex, age class, year or season for the British hedgehogs tested. In most PCR-positive animals (19/22) from which liver and brain were tested separately, both were PCR-positive. Sanger sequencing of amplicons from 59 British hedgehogs revealed at least two novel viruses within the Gammaherpesvirinae. Thirteen of these hedgehogs had liver and brain tissues screened for microscopic abnormalities, of which one had non-suppurative meningoencephalitis, but neither intranuclear inclusion bodies nor herpesvirus virions (on electron microscopical examination) were identified. Sequencing of the whole DNA polymerase gene confirmed two genetically different Human alphaherpesvirus 1 viruses in the Swedish and Swiss hedgehogs.

Highlights

Whilst a range of infectious agents have been detected in hedgehogs[4], investigations of viral aetiologies have typically been restricted to single case reports
In Great Britain, the polymerase chain reaction (PCR)-positive hedgehogs had a wide spatial distribution with no apparent evidence of geographical clustering, except that expected from a convenience sample. These findings indicate that HHGHV-1 is endemic in the free-living hedgehog population in Great Britain, with infection being spatio-temporally widespread at moderately high occurrence
HHGHV-2a and HHGHV-2b were each found in only one hedgehog and whether these viruses are endemic in the British hedgehog population requires examination and sequencing of HHGHVs from a larger sample of hedgehogs across Great Britain

Summary

Introduction

Whilst a range of infectious agents have been detected in hedgehogs[4], investigations of viral aetiologies have typically been restricted to single case reports. Herpesvirus-like particles were observed on TEM examination of the liver of a three-month old female Western European hedgehog, held in captivity for hand rearing, which died with multifocal necrotising hepatitis in Sweden. In this case, virus isolation in primary bovine foetal skin cells revealed a cytopathic effect www.nature.com/scientificreports/. Human alphaherpesvirus 1 and 2 (genus Simplexvirus, subfamily Alphaherpesvirinae) antigen was visualised using immunohistochemistry in the brain of a young female Western European hedgehog in a Swiss rehabilitation centre This animal, originally free-living, showed neurological clinical signs and died despite treatment. The aims of this study were to investigate the occurrence of herpesvirus infections in free-living Western European hedgehogs in Great Britain, to characterise these herpesviruses and those previously detected, and to assess the clinical significance of the identified herpesvirus infections in this host

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