SymptomsBy Mayo Clinic staff
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Most people with viral encephalitis have either no symptoms or mild flu-like symptoms, such as the following:
- Aches in muscles or joints
- Fatigue or weakness
More-serious cases require prompt medical care. Signs and symptoms may include the following:
- Severe headache
- Altered consciousness
- Confusion or agitation
- Personality changes
- Loss of sensation or paralysis in certain areas of the body
- Muscle weakness
- Double vision
- Perception of foul smells
- Problems with speech or hearing
- Loss of consciousness
Signs and symptoms in infants and young children may also include:
- Bulging in the soft spots (fontanels) of the skull in infants
- Nausea and vomiting
- Body stiffness
- Constant, inconsolable crying
- Crying that worsens when the child is picked up
- Poor feeding
When to see a doctor
Get immediate care if you or someone you know is experiencing any of the symptoms associated with more-severe cases of encephalitis. Severe headache, fever and altered consciousness — almost always present with encephalitis in older children and adults — require urgent care.
Infants and young children with any signs or symptoms of encephalitis should receive urgent care.
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