September 10, 2009

 

Dear Clients:

 

This letter is intended to emphasize the importance of vaccinating our horses for West Nile Virus. West Nile Virus can cause a spectrum of disease related to inflammation of the brain and lining of the brain and spinal cord. The disease can manifest as ataxia (loss of balance), lethargy, droopy eyelids, fever, and can progress to severe neurological disease including falling down, seizures and death. Last year, there was a dramatic increase in the prevalence (38 confirmed cases) in our Washington State horse population.   This year, Washington State leads the country in equine West-Nile cases reported.

 

Due to this increased prevalence, we feel it is very important to take these three steps in preventing the disease:

 

1)          Preventing the mosquito (the transmitter of the virus) from growing:

We can interrupt the mosquito life cycle by cleaning water sources every 3 days, draining all unessential accumulations of water (gutter run off, tarp pools, tires and cans), and filling in pasture puddles. If necessary, additional environmental insecticide techniques can be found on the Washington State Department of Health web site.

 

2)          Preventing the mosquito from biting:

Mosquito’s peak biting periods are dawn and dusk. Limiting our horses to the outdoor environment during these times can reduce transmission of West Nile Virus. Keeping horses under a fan or keeping them blanketed decreases the mosquito’s access to our horses. Application of pyrethrin (or other repellant) to the horses fly sheet/blanket can decrease insect bites as well.

 

3)          VACCINATE      VACCINATE      VACCINATE   

Preventing the virus from causing clinical disease once it has been transmitted:

We can prevent clinical West Nile Virus disease by vaccinating our horses. The vaccine is available in modified live and killed forms. We are now using both Prevenile modified live vaccine and West Nile killed vaccine depending on the circumstance. The vaccine is restricted to the use by licensed veterinarians.

 

We strongly recommend these protocols to prevent clinical West Nile Virus disease. If you suspect your horse may have West Nile Virus, please call us to arrange testing and treatment. As always, please call us with any questions.

 

Sincerely,