West Nile Virus: Is Your Horse In Danger?

West Nile Virus was in the news a lot last year. But do you really need to worry about your horse getting the virus?

Since there is no specific treatment for West Nile Virus only supportive care, the answer is found in prevention. There are two primary ways horse lovers can ensure their animals are safe.

Vaccination Protocol
Since West Nile Virus (WNV) is a relatively new disease in California, horses have no natural immunity. Fortunately, there is a safe vaccine to prevent the disease in horses. It is your first line of defense. Here is the protocol to protect your horse:

If your horse has never been vaccinated, call us right away. Our doctors will provide an initial vaccine, and then, 3-6 weeks later, a booster will be given. If a horse had an initial vaccine but did not get the second booster, it will need to start the two-shot series over. Horses that have been vaccinated for WNV should receive a booster every 6 months. Most clients like the convenience of coordinating the WNV vaccine with other vaccines that may be due.

Mosquito Abatement Protocol
The second way to prevent WNV is to take precautions with your horse or horses and around your property. Here are a few tactics:
• Eliminate standing water
• Clean water troughs
• Keep horses in screened-in areas or barns at night
• Use repellents
• Consider utilizing environmentally safe fish that eat the mosquito larvae
• Put mosquito dunks in ponds and irrigation ditches

According to the State of California West Nile Virus Website, 456 horses tested positive for the disease in California and 200 have died. Since this mosquito-borne virus causes encephalitis or inflammation of the brain lining and spinal cord, it is very serious. The severity of WNV varies from animal to animal. Some horses might experience only mild fever and malaise, others — particularly older or weakened horses — may suffer much more serious symptoms. About 35 percent of the horses that get WNV will die, and of the surviving horses many will have lasting problems.

West Nile Virus Symptoms
Please contact us immediately if you notice any of the following ailments that are sometimes symptoms of WNV:
• Muscle trembling
• Skin twitching
• Ataxia (stumbling)
• Weakness
• Sleepiness
• Facial paralysis
• Difficulty urinating/deficating
• Blindness

Also, be aware of dead birds around your property, as this can be an indication that infected mosquitoes are in the area. Some species of wild birds, particularly crows and jays, are very susceptible to WNV and can die from the infection.

How the Disease Is Transmitted
The first case of WNV in the U.S. was identified in New York in 1999. The disease steadily traveled west across the country following the migratory patterns of birds. Mosquitoes are WNV carriers (“vectors”) that become infected when they feed on infected birds. Infected mosquitoes can then spread WNV to humans and other animals when they bite.
The disease cannot be spread from horse to horse, or from horse to human. However, WNV can cross the placenta and the mare can infect the unborn foal.

For more information about WNV, please visit http://www.westnile.ca.gov,
or call toll free: 1-877-WNV-BIRD (1-877-968-2473).