Equine rotaviruses--current understanding and continuing challenges

Abstract

Equine rotaviruses were first detected in foals over 30 years ago and remain a major cause of infectious diarrhoea in foals. During this time, there has been substantial progress in the development of sensitive methods to detect rotaviruses in foals, enabling surveillance of the genotypes present in various horse populations. However, there has been limited epidemiological investigation into the significance of these circulating genotypes, their correlation with disease and the use of vaccination in these animal populations. Our knowledge of the pathogenesis of rotavirus infection in foals is based on a limited number of studies on a small number of foals and, therefore, most of our understanding in this area has been extrapolated from studies in other species. Questions such as the concentrations of rotavirus particles shed in the faeces of infected foals, both with and without diarrhoea, and factors determining the presence or absence of clinical disease remain to be investigated, as does the relative and absolute efficacy of currently available vaccines. The answer to these questions may help direct research into the development of more effective control measures.

Keywords: BLS; Brucella spp. lumazine synthase; DLPs; Diarrhoea; ELISA; EM; Equine rotavirus; Foal; G; P; PCR; RT-LAMP; RT-PCR; Review; SLPs; TLPs; Virus; double-layered particles; electron microscopy; enzyme-linked immunosorbent assay; glycoprotein; polymerase chain reaction; protease sensitive protein; reverse transcription loop-mediated isothermal amplification; reverse transcription polymerase chain reaction; single-layered particles; triple-layered particles.

Fig. 1

Rotavirus particles as seen by negatively stained electron microscopy.

Fig. 2

Schematic representation of the equine rotavirus genomic electrophoretic pattern and the virion morphology including triple-layered particles (TLPs), double-layered particles (DLPs) and single-layered particles (SLPs).