What Is the Agent of Meningitis?

Meningitis occurs when the membrane surrounding the brain or spinal cord becomes inflamed. Usually this indicates a bacterial or viral infection.

Bacterial Meningitis

• According to the Centers for Disease Control (CDC), bacteria called Neisseria meningitidis and Streptococcus pneumoniae cause the vast majority of bacterial meningitis cases.

Viral Meningitis

• A variety of different viruses may lead to viral meningitis, including enteroviruses, herpesvirus, measles, mumps and influenza.

Viral vs. Bacterial Meningitis

• Viral meningitis causes most cases of meningitis. However, the more serious form to the patient remains bacterial meningitis. According to Children's Hospital Boston, the viral form will usually go away on its own in 3 to 10 days, while the bacterial form can cause death without treatment.

Symptoms

• Bacterial and viral meningitis have a similar set of symptoms: confusion, drowsiness, fever, stiff neck, sensitivity to light, and headache. Bacterial meningitis may also cause additional symptoms: a rash, nausea, vomiting and sore throat.

Non-Infectious Meningitis

• In much rarer cases, meningitis may occur without an infection due to a bacteria or virus. Cancer and some pharmaceutical drugs can cause meningitis. Other medical conditions with the potential to inflame the membrane around the brain and spinal cord could potentially cause meningitis.