Equine Viral Encephalitis and West Nile Virus

Equine Viral Encephalitis

What equine viral sign can be due to many different viruses? In North America, rabies, WNV, Eastern and Western encephalitis, and neurotropic presentation of equine herpesvirus can all cause this. Good history taking and anamnesis all help determine the specific cause.

West Nile Virus

Which virus is one cause of equine viral encephalitis? It is a flaviviridae, is RNA and enveloped, and is in a complex along with St. Louis encephalitis, Murray valley encephalitis, and Japanese encephalitis. It is now endemic to the US. The regular hosts are birds and mosquitoes, which transfer to humans and horses, which are both dead-end hosts. It is abbreviated WNV.

Flaviviridae

Which family includes WNV?

RNA

Is WNV RNA or DNA?

Enveloped

Is WNV enveloped or naked?

Yes

Is WNV an arbovirus and zoonosis?

Dead-end

What type of host is the horse, and humans, for WNV?

Yes

Are fever, muscle twitching, incoordination, weakness, behavioral change, cranial nerve deficits, difficulty swallowing, seizures, and sensitivity all signs of WNV in horses? Typically cases are asymptomatic.

IgM ELISA

What serological test is the main one to diagnose WNV? RT-PCR, IHC, and IF are other options. It should be differentiated from Eastern/Western Equine Encephalitis, Rabies, and Equine Herpesvirus 1.

Yes

Are inactivated vaccines an option for WNV in horses? Recombinant and DNA are available for humans.