NOVEL EQUINE HEPATITIS VIRUSES: ARE THEY CLINICALLY RELEVANT?

摘要

Acute hepatitis m horses (serum hepatitis, Theiler s disease) has frequently been associated with the antecedent administration of biologies of equine origin. The etiology is unknown but the occurrence of disease following parenteral administration ofbiologies produced in horses, the significant delay between exposure to biologies and the onset of acute hepatitis, and the histopathologic lesions in the liver are remarkably similar to those associated with acute human hepatitis A virus or hepatitis Bvirus infections, suggesting that acute hepatitis in horses may have a similar viral etiology. The human hepatitis viruses are now well characterized and tests are available for diagnosis and for preventing transmission via blood or plasma products. Recently, an outbreak of serum hepatitis in horses was associated with an infection of a highly divergent, previously unrecognized Flavivirus (Chandriani et al. 2013) with phylogenic closeness to human hepatitis C virus (HCV). This Theiler's disease associated virus (TDAV) is one of three, new, blood-borne Flaviviruses that have been described in horses since June 2012 (Burbelo PD et al 2012; Kapoor A et al 2013). All have been identified by direct metagenomic analysis using unbiased, high-throughput sequencing (next generation sequencing [NGS]). The following is a brief summary describing TDAV and the other two related horse viruses, the non-primate hepacivirus (NPHV) and the equine pegivirus (EPgV).