Signs and Symptoms
- Severe persistent headache
- A stiff neck
- Sensitivity to light
- Mental changes
Other symptoms may include confusion, nausea, vomiting, a red or purple rash, and seizures. An elderly person may be lethargic and show few other signs. People with weakened immune systems may have atypical symptoms. Infants may be irritable and cry when they are held, vomit, have body stiffness, have seizures, refuse food, and have bulging fontanels (the soft spots on the top of the head).
Encephalitis symptoms may also include neurological problems such as difficulty with hearing or speech, loss of sensation, partial paralysis, seizures, hallucinations, muscle weakness, changes in personality, and coma.
Complications and Prognosis
The outcome of those with meningitis and encephalitis depends on the specific cause of the condition, the severity, the person's health and immune status, and how quickly the condition is identified and treated. Those with mild cases may recover fully within a few weeks or may have persistent or permanent complications.
As many as 15-25% of newborns and 15% of other patients with bacterial meningitis die, even when treated appropriately and rapidly. Up to 15-25% of those who survive may have neurological complications (sequelae), including accumulation of fluid within the brain (hydrocephalus), deafness, blindness, periodic seizures, and/or some degree of impaired thinking processes. These complications may occur at any age, but newborns are at the highest risk.