Polioviruses

Poliomyelitis (acute flaccid paralysis)

Aseptic meningitis

Global

Incidence now low because of vaccine

None

Vaccines: Live (oral), killed (injected)

Alphaviruses (some), mosquito-borne

Western equine encephalitis

North and South America

None

Vaccine available to protect equines

Investigational vaccine used in at-risk laboratory workers

Eastern equine encephalitis

North America, South America (Madariaga)

None

Vaccine available to protect equines

Investigational vaccine used in laboratory workers at risk

Venezuelan equine encephalitis

Gulf states to South America

None

Vaccine available for equines

Investigational vaccine used in laboratory workers at risk

Flaviviruses (some), mosquito-borne

Japanese encephalitis

Southeast Asia, Japan, Korea, China, India, Philippines, eastern former Soviet Union

None

Vaccine

Murray Valley encephalitis

Australia, New Guinea

None

None

St. Louis encephalitis

North and South America

None

None

West Nile virus encephalitis

Africa, Middle East, southern France, former Soviet Union, India, Indonesia, US, Canada, South America (Argentina, Brazil)

None

Screening blood and blood products for the virus

Vaccine available for equines

Flaviviruses (some), tick-borne

Powassan encephalitis

Canada, northeastern and upper midwestern US

None

None

Tick-borne encephalitis

Eastern and Central Europe, Balkans, former Soviet Union

Outbreaks that coincide with periods of tick activity

None

Vaccine

Orthobunyaviruses (some), mosquito-borne

California encephalitis and related types (eg, La Crosse encephalitis)

Probably worldwide

Common in midwestern and eastern US

Symptomatic infection primarily in children

None

None

Mammarenaviruses (some)

Lymphocytic choriomeningitis

US, Europe, possibly elsewhere

Chief reservoir: House mouse

Primarily in adults during autumn and winter

None

None

Rabies virus

Rabies

Worldwide

None

Vaccine

Vaccinate pets