West Nile encephalitis

medical condition

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Last updated

July 22, 2026

Quick Summary

West Nile encephalitis is a severe form of West Nile virus infection that causes inflammation of the brain. The West Nile virus, belonging to the Flaviviridae family, is primarily an infection of birds but can be transmitted to humans through mosquito bites.12

While most human infections are mild or asymptomatic, in some cases, the virus can affect the central nervous system. Symptoms of West Nile encephalitis include headache, fever, stiff neck, disorientation, and muscle weakness, and can be fatal. There is no specific treatment for West Nile virus infection; care is supportive, focusing on managing symptoms and preventing secondary infections. Prevention involves mosquito control and personal protective measures like using insect repellent and covering skin.23

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encephalitis
Epidemics of encephalitis
…States was the largest human encephalitis outbreak recorded in the Western Hemisphere at the time. EEE virus is also found in the United States, where it is a rare cause of illness. It occurs most commonly along the East Coast but is also found in the Great Lakes region. About…
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…States was the largest human encephalitis outbreak recorded in the Western Hemisphere at the time. EEE virus is also found in the United States, where it is a rare cause of illness. It occurs most commonly along the East Coast but is also found in the Great Lakes region. About…
Read More

West Nile virus
West Nile virus infection
…reaches the brain, resulting in West Nile encephalitis, symptoms of which include headache, fever, neck stiffness, disorientation, and muscle weakness. Death may result. Alternatively, spread of the virus to the CNS can cause West Nile meningitis, a distinguishing symptom of which is stiff neck, or West Nile poliomyelitis, a syndrome…
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…reaches the brain, resulting in West Nile encephalitis, symptoms of which include headache, fever, neck stiffness, disorientation, and muscle weakness. Death may result. Alternatively, spread of the virus to the CNS can cause West Nile meningitis, a distinguishing symptom of which is stiff neck, or West Nile poliomyelitis, a syndrome…
Read More