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June 1, 2010

NYS Veterinarian Suggests that Horses Be Vaccinated Against EEE

With the summer season upon us, now is the time for horse owners to get their horses vaccinated against the Eastern equine encephalitis (EEE) virus. This virus along with other types of equine encephalitis and West Nile Virus belong to a group of viral diseases known as "arboviruses" which are spread by insects and similar organisms. Commonly found near wetland habitats, the EEE virus multiplies in wild birds and is then transmitted by mosquitoes to horses and people.

"Horses are particularly susceptible to the infection because they are outdoors and are fed upon by mosquitoes which can carry the virus," said Dr. David Smith, acting New York State veterinarian. "Accordingly, owners should protect their horses against EEE and other arboviruses like West Nile Virus with a vaccination.

"While no vaccine is 100 percent effective in preventing illness, the chance of infection is much lower for EEE-vaccinated horses than for non-vaccinated horses," continued Dr. Smith.

According to Smith, the symptoms of the disease in horses are vary greatly, ranging from barely noticeable to signs such as staggering, blindness, and unconsciousness. In horses showing visible signs of disease, 50 to 90 percent of cases may be fatal.

Vaccinations should be given by a licensed veterinarian to ensure that the vaccine used is effective and the injections are given correctly. Properly administered vaccinations are effective for one year and follow-up boosters are required on an annual basis.

While vaccination is the best way to protect horses, horse owners can build on this defense with additional precautions. Minimizing standing water and changing water in horse troughs at least twice a week can help discourage mosquito breeding.

Dr. Smith added, "While EEE virus infections are rare, they continue to be a threat each year to horses and humans. Horse owners need to prepare now for possible EEE activity in the upcoming months."

For a complete vaccination and booster schedule, contact your veterinarian.


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