In vitro susceptibility of six isolates of equine herpesvirus 1 to acyclovir, ganciclovir, cidofovir, adefovir, PMEDAP and foscarnet

International audienc

The protective properties of vaccination against equine herpesvirus 1-induced viremia, abortion and nervous system disorders

Equine herpesvirus (EHV) 1 is an important pathogen of horses. Upon infection, the virus replicates in the upper respiratory tract. Then it spreads to internal organs via a cell-associated viremia. Local replication in internal organs may result in abortion and nervous system disorders. The currently designed vaccines are not able to induce significant protection against EHV1-induced viremia. However, several vaccines are able to induce a significant level of protection against either abortion or nervous system disorders. Which immune responses correlate with this protection is so far unknown. Besides vaccination, management will remain a crucial factor in the prevention of EHV1-induced clinical signs. Management measures include the vaccination of all horses on the premises to reduce infection pressure; the separate housing of young horses, adult horses and pregnant mares; strict hygiene measures and strict control of contact with horses from outside the premises. If, despite vaccination and thorough management, an outbreak of EHV1-induced disease occurs, treatment with antiviral agents may be useful

The pathogenesis and immune evasive mechanisms of equine herpesvirus type 1

Equine herpesvirus type 1 (EHV-1) is an alphaherpesvirus related to pseudorabies virus (PRV) and varicella-zoster virus (VZV). This virus is one of the major pathogens affecting horses worldwide. EHV-1 is responsible for respiratory disorders, abortion, neonatal foal death and equine herpes myeloencephalopathy (EHM). Over the last decade, EHV-1 has received growing attention due to the frequent outbreaks of abortions and/or EHM causing serious economical losses to the horse industry worldwide. To date, there are no effective antiviral drugs and current vaccines do not provide full protection against EHV-1-associated diseases. Therefore, there is an urgent need to gain a better understanding of the pathogenesis of EHV-1 in order to develop effective therapies. The main objective of this review is to provide state-of-the-art information on the pathogenesis of EHV-1. We also highlight recent findings on EHV-1 immune evasive strategies at the level of the upper respiratory tract, blood circulation and endothelium of target organs allowing the virus to disseminate undetected in the host. Finally, we discuss novel approaches for drug development based on our current knowledge of the pathogenesis of EHV-1

Evaluation of orally administered valacyclovir in experimentally EHV1-infected ponies

International audienc