St. Louis Encephalitis Symptoms & Diagnosis

Symptoms

St. Louis encephalitis can result in a wide range of symptoms, or produce no symptoms at all. The disease can be mild, severe, or even fatal. The disease is fatal in 3%-30% of people who develop symptoms. Symptoms associated with St. Louis encephalitis usually appear 5-15 days after the bite of an infected mosquito and may include:

• Headache
• Fever
• Neck stiffness
• Stupor
• Disorientation
• Coma
• Tremors
• Convulsions (especially in infants)
• Paralysis

Diagnosis

Your doctor will ask about your symptoms and medical history, and perform a physical exam. He or she will also perform blood tests to identify the virus.