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St. Louis Encephalitis

St. Louis Encephalitis is viral disease that is spread to humans through the bite of an infected mosquito. Mosquitoes pass the virus from birds to humans. It was the most common mosquito borne disease in the United States prior to the introduction of West Nile in 1999.

Signs & Symptoms: appear 4-21 days after being bitten. Most people are asymptomatic (without symptoms) but symptoms can include:

• Headache
• Fever
• Neck stiffness
• Disorientation
• Tremors
• Seizures
• Spastic Paralysis
• Meningitis
• Encephalitis
• Coma

The disease is generally milder in children, but there is a high rate of encephalitis (inflammation of the brain). People age 50 and over are at highest risk for severe disease and death.