For vaccination of healthy horses 10 months of age or older as an aid in the prevention of viremia caused by West Nile virus, and as an aid in the prevention of equine encephalomyelitis due to Eastern and Western viruses, and tetanus. Dose: Horses, inject one 1 mL dose intramuscularly using aseptic technique. Administer a second 1 mL dose 3 to 4 weeks after the first dose. A 1 mL booster dose should be given annually. Early revaccination may be advisable when horses are faced with an outbreak or with other conditions which might make heavy exposure likely. Preservatives: Thimerosal, neomycin and polymyxin B.