The goal of this project is to develop an effective DNA vaccine for equine herpesvirus to protect horses against infection and disease and to prevent EHV outbreaks in the US.

Ongoing EHV-1 outbreaks, including cases of neurologic disease caused by EHV-1 and called ‘equine herpesvirus myeloencephalopathy’ (EHM), emphasize the fact that currently available EHV-1 vaccines are not fully protective. These disease outbreaks are occurring despite widely used vaccination and many available EHV vaccines on the market. The fact that currently available inactivated or attenuated vaccines have not been sufficient to completely protect from EHV-1 outbreaks has caused the demand for novel EHV vaccine formulations that can prevent horses from infection and severe disease, especially neurologic disease. Here, we propose to design and evaluate a novel DNA vaccine formulation against EHV-1/EHM for horses. We are combining our expertise in equine immunology and EHV-1 research (Dr. Wagner) and virology and vaccine design (Dr. Diel) to first perform a comprehensive analysis of the best DNA vaccine candidate and then test the optimized vaccine candidate for its protective effects in horses. The DNA vaccine platform that we are testing in this project has already been used successfully for induction of immunity and protection from infectious disease in other species. The project will result in an established new EHV vaccine candidate and provide a new approach to effectively protect horses from EHV-1 infection and disease. Overall, the project is relevant to the prevention of disease induced by EHV-1 by increasing immunity and protection in the equine population and reducing severe neurological disease outbreaks in the US.