The Emergence of Viral Encephalitis in Donkeys by Equid Herpesvirus 8 in China.

Tongtong Wang,Tianjiao Wang,Leyu Hu,Ying Li,Yubao Li,Xinyao Hu,Wei Zhang,Liangliang Li,Huiying Ren,Changfa Wang,Yonghui Wang,Wenqiang Liu,Mengyuan Liu

doi:10.3389/fmicb.2022.840754

Abstract

The equine herpesvirus type 8 (EHV-8) can cause significant economic losses in the global horses and donkey industry. The disease has been associated with abortion and respiratory symptoms. However, it is rare for a study to be reported about donkeys with neurological diseases induced by EHV-8 infection. In the present study, one 2-year-old male donkey, from a large-scale donkey farm in China, died with a severe neurological disorder. The causative agent, donkey/Shandong/10/2021 (GenBank accession: OL856098), was identified and isolated from the brain tissue of the dead donkey. Meanwhile, BALB/c mice were used as an animal model to evaluate the pathogenicity of the EHV-8 isolate. Our data showed that EHV-8 was positive in brains by PCR and immunohistochemistry, which induced typical viral encephalitis lesions in both donkey and mice consistent with clinical signs. For the first time, we reported that EHV-8 had been isolated from donkeys with a neurological illness in China, which is helpful to reveal the pathogenicity of EHV-8 in the donkey.

Highlights

The equine herpesviruses are infectious pathogens that cause serious respiratory diseases and abortion in the equine or donkey industry
The histological examination confirmed that the brain tissue exhibited typical viral encephalitis with perivascular cuffing characterized by lymphocyte infiltration (Figure 1B) and neuronophagia and satellitosis of glial cells characterized by neurons surrounded or phagocytized by gitter cells (Figure 1C)
The PCR/RT-PCR results have proven the brain tissue to be negative for H3N8 (1,027 bp), EAV (333 bp), JEV (500 bp), WNV (559 bp), EHV-1 (792 bp), and EHV-4 (1,591 bp) using specific detecting primers to these viruses but positive for equine herpesvirus type 8 (EHV-8), a predicted 1,236-bp (EHV-8 ORF70) product that was

Summary

Introduction

The equine herpesviruses are infectious pathogens that cause serious respiratory diseases and abortion in the equine or donkey industry. Horses were considered the natural host to EHV-1–5, while donkeys are for EHV-6–8 (asinine herpesvirus types 1–3, AHV-1–3) (Browning et al, 1988; Azab et al, 2011; Garvey et al, 2018). EHV-8, a double-stranded enveloped DNA virus 150 kb in length and which contains 76 open reading frames (ORFs) at least (Garvey et al, 2018), has been reported in many countries since it was first isolated from a donkey in Australia in 1987 (Browning et al, 1988). It has been reported to be present in donkeys in Israel in 2020 (Schvartz et al, 2020). This disease causes serious respiratory disorders and abortion in equine animals. The neurological disease induced by EHV-8 in donkeys is limited

Methods

Results

Conclusion