Meningitis is an inflammation of the membranes (meninges) surrounding your brain and spinal cord.
The swelling from meningitis typically triggers symptoms such as headache, fever and a stiff neck.
Most cases of meningitis in the United States are caused by a viral infection, but bacterial, parasitic and fungal infections are other causes. Some cases of meningitis improve without treatment in a few weeks. Others can be life-threatening and require emergency antibiotic treatment.
Seek immediate medical care if you suspect that someone has meningitis. Early treatment of bacterial meningitis can prevent serious complications.