The Neuroendocrine System: Lecture Transcript

© Copyright 2003 by P.J. Broadfoot, D.V.M., USA
(Explore Issue: Volume 12, Number 4)

As a primarily small animal practitioner, due to time constraints, I have only limited contact with horses, except for those clients who insist that I am still an equine practitioner. As a result, I have not had much opportunity to deal with the current pandemic of West Nile Virus. However, late summer saw me grasping for new knowledge of this disease, as I was faced with several cases, starting with one of my own animals.

By way of introduction, a review of the disease might be in order. The etiology is an arbovirus of the genus Flaviviridae, carried by mosquitoes. The most likely vector is birds, as horses are not generally recognized as developing a high enough viral load to be infective, so they are, in effect, a dead end host.
Clinical Signs of West Nile Virus in Horses:

1. Stumbling or Tripping
2. Muscle Weakness or Twitching
3. Partial Paralysis
4. Loss of Appetite
5. Depression or Lethargy
6. Head Pressing or Head Tilt
7. Impaired Vision
8. Wandering or Circling
9. Inability to Swallow
10. Inability to Stand Up
11. Fever
12. Convulsions
13. Coma
14. Death