Equine Encephalitis

Affecting horses and humans, equine encephalitis is a type of inflammation of the brain. The different forms include eastern, western, and Venezuelan. Fewer than ten human cases are seen annually in the United States. In South and Central America, epidemics of the Venezuelan form of the disease have killed thousands of people.

Types of Encephalitis

What Is Equine Encephalitis?

Equine encephalitis is an inflammation of the brain that affects horses and humans.

Eastern Equine Encephalitis

Eastern equine encephalitis also infects birds that live in freshwater swamps of the eastern U.S. seaboard and along the Gulf Coast.

In humans, symptoms are seen four to ten days following transmission and include:

Sudden fever
General flu-like muscle pains
Headache of increasing severity
Coma and death (in severe cases).

About half of all infected patients die from eastern equine encephalitis.

Fewer than ten cases in humans are seen annually in the United States.

Western Equine Encephalitis

Western equine encephalitis is seen in farming areas in the Western and Central Plains states.

With this form, symptoms begin five to ten days following infection. Children, particularly those under 12 months of age, are affected more severely by western equine encephalitis than adults and may have permanent neurological damage.

Death occurs in about 3 percent of cases.

Venezuelan Equine Encephalitis

Venezuelan equine encephalitis is rare in this country. Children are at greatest risk of developing severe complications from it, while adults generally develop flu-like symptoms.

Epidemics of Venezuelan equine encephalitis in South and Central America have killed thousands of people and left others with permanent, severe neurological damage.