Symptoms include muscle stiffness and rigidity, flared nostrils, hypersensitivity, and the legs stiffly held in a sawhorse stance. As the disease progresses, muscles in the jaw and face stiffen, preventing the animal from eating or drinking. More than 80 percent of affected horses die. All horses should be immunized annually against tetanus. Additional boosters for mares and foals may be recommended by your veterinarian.
Available vaccines are inexpensive, safe, and provide good protection.
WEE has been noted throughout North America, while EEE appears only in the east and southeast. VEE, the Venezuelan variety, has not been seen in the United States for many years. However, a recent outbreak of VEE occurred in Mexico. Sleeping sickness is most often transmitted by mosquitos, after the insects have acquired the virus from birds and rodents. Symptoms vary widely, but all result from the degeneration of the brain.