Merck Unveils Websites to Help Owners Understand EPM, WNV

Equine protozoal myeloencephalitis (EPM) and West Nile virus (WNV) are two diagnoses veterinarians don't want to give and horse owners dread hearing. To help horse owners in the United States stay up-to-date on the latest information regarding these diseases, Merck Animal Health has developed two new comprehensive websites: and

EPM Resource Center
EPM is a progressive and potentially fatal infection of the central nervous system caused by the single-celled protozoal microorganism Sarcocystis neurona. Because the disease is progressive, early detection and veterinary intervention are critical to the horse's chance of recovery. offers a centralized location for horse owners to research EPM and learn to recognize the early onset of the disease. The website is designed to provide owners with:

  • Up-to-date disease information and research;
  • News and events surrounding EPM;
  • Management strategies to aid in prevention of EPM; and
  • Treatment options to discuss with their veterinarian.

"EPM can cause irreversible damage to the horse's brain or spinal cord and is more likely to cause permanent damage if the disease is not detected early," said Wendy Vaala, VMD, Dipl. ACVIM, senior equine technical services veterinarian for Merck Animal Health. "Although EPM only affects less than 1% of horses, it is critical that owners know what to do, just in case. Owners can increase their horse's chance of a full recovery by talking to their veterinarian and educating themselves through websites like"

WNV Information and More
Though less evasive than EPM, WNV infection is still a threat in the United States. According to Merck, provides horse owners with many educational resources on WNV, as well as information on vaccines that aid in helping prevent this disease.

"We see cases of West Nile virus in horses every year in the United States," said Craig Barnett, DVM, senior equine technical services veterinarian for Merck Animal Health. "West Nile is still a threat to our horses, and it is important for owners to understand the disease and, more importantly, understand the need for prevention."

In addition to providing horse owners with information on WNV, also includes information on vaccinations and other important equine diseases including:

  • Eastern equine encephalomyelitis;
  • Western equine encephalomyelitis;
  • Rabies;
  • Tetanus;
  • Equine influenza; and
  • Equine herpesvirus.

The site also provides information on Merck Animal Health's new WNV vaccine portfolio.

To learn more about Merck Animal Health's entire product portfolio visit Veterinarians also can learn more by contacting their distributor or sales representative. Horse owners can learn more by contacting their veterinarian.

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