West Nile in Horses and Birds

West Nile virus is an insect-borne disease most commonly spread by infected mosquitoes. A recent sampling of mosquitos in Cedar Park tested positive for West Nile, and 958 mosquito pools in Texas have tested positive this year, according to the Texas Department of State Health Services.

In humans, West Nile can cause inflammation of the brain and spinal cord linings (meningitis), brain inflammation (encephalitis) or fever. Approximately 20 percent of those infected develop a fever, but only about 1 in 150 show more serious symptoms, according to the CDC.

Among pets and other animals, West Nile most seriously affects birds and horses, primarily in their brains and nervous systems. In horses, symptoms can include muscle tremors and twitching, hypersensitivity to touch or sound, walking in circles, falling or stumbling. If the disease progresses, more serious symptoms can develop, like seizures, trouble standing, or even death. Birds rarely display any symptoms, though the virus can make them more susceptible to other illnesses.

Fortunately, although dogs and cats can be infected with the West Nile virus from a mosquito bite, they are very resistant to developing West Nile disease. However, in an abundance of caution, if your dog or cat starts to show symptoms of a neurological problem — seizures, tremors, spasms, confusion, or paralysis, etc., Block House Creek encourages you to have one of our veterinarians evaluate your precious pet as soon as possible. Such symptoms most likely are the result of other diseases or issues that may need treatment.

No vaccine exists for West Nile, itself. However, two vaccines have shown to be effective in lowering a horse’s risk of developing encephalitis from West Nile. Initially, the horse is given two doses three to six weeks apart followed by a booster. Talk to one of our vets for recommendations about what might be most effective and appropriate for your animal.

Prevention by avoiding exposure to mosquitos is the first line of defense against equine encephalitis. Stable horses indoors during dawn and dusk, when mosquitos are most active. Using fans can be helpful in keeping mosquitos from landing on your horse. If your horse does become infected, quarantine or isolation is not necessary because West Nile cannot be transmitted from a horse to another animal or person.

As always, eliminate any sources of standing water where mosquitos breed, including troughs, pet water bowls, large puddles, birdbaths, etc. If you have any questions or concerns about possible West Nile in your horse or bird, we will be glad to help.