Eastern equine encephalitis is a zoonotic viral disease caused by the Eastern equine encephalitis virus. It mainly affects horses and humans. Because the disease was prevalent in horse herds on some farms in the eastern United States in 1933, and the virus was isolated from sick horses by Ten Broeck and Merrill in the same year, it was named Eastern equine encephalitis. Clinically, high fever and central nervous system symptoms are the main symptoms. People are infected accidentally, but the mortality rate can be as high as 50%. The incubation period of Eastern equine encephalitis is 7 to 10 days. Some patients have prodromal symptoms such as fatigue, lack of appetite, abdominal pain, sore throat, and headache.