Merck Manual

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Arboviruses That Can Cause or Are Linked to Equine Encephalomyelitis

Arboviruses That Can Cause or Are Linked to Equine Encephalomyelitis

Virus Species or Variant

Geographic Location

Most Important Reservoir

Alphaviruses

North American Eastern equine encephalitis virus

Eastern North America, primarily east of Mississippi river

Birds

Madariaga virus

South America, Caribbean

Rodents

Western equine encephalitis virus

Western South America

Birds, rabbits, and snakes

Highlands J virus

Birds

Venezuelan equine encephalitis virus

Central and South America, Caribbean

Cotton rat and other rodents

Everglades virus

South Florida (USA)

Rodents

Ross River virus

Australia, Papua New Guinea

Marsupial and placental mammals

Semliki Forest virus

East and West Africa

Unknown

Una virus

South America

Birds

Flaviviruses

Japanese encephalitis

Asia, India, Russia, Western Pacific

Birds, swine

Murray Valley

Australia, Papua New Guinea

Birds, marsupials, and foxes

Kunjin virus

Australia

Birds (herons and ibis)

St. Louis encephalitis

North, Central, and South America

Birds

Usutu

Europe, Africa

Birds

West Nile

Africa, Middle East, Europe, North, Central, and South America, Australia

Passerine birds

Louping ill

Iberian Peninsula, UK

Sheep, grouse

Powassan

North America, Russia

Lagomorphs, rodents, mice, skunks

Tickborne encephalitis

Asia, Europe, Finland, Russia

Small rodents