Spinal meningitis, or meningitis, is a condition in which the membranes that surround the brain and spinal cord become inflamed. It is also known as bacterial meningitis, viral meningitis, or meningococcal meningitis. The most common cause of meningitis is a viral infection, however, it may also be caused by fungal and bacterial infections. Meningitis is a serious medical condition that can be life-threatening. Less than 1 in 100,000 people in the United States are infected with bacterial meningitis every year.