Risk factors

Risk factors for meningitis include:

• Skipping vaccinations. Risk rises for anyone who hasn't completed the recommended childhood or adult vaccination schedule.
• Age. Most cases of viral meningitis occur in children younger than age 5. Bacterial meningitis is common in those under age 20.
• Living in a community setting. College students living in dormitories, personnel on military bases, and children in boarding schools and child care facilities are at greater risk of meningococcal meningitis. This is probably because the bacterium is spread through the respiratory route, and spreads quickly through large groups.
• Pregnancy. Pregnancy increases the risk of listeriosis — an infection caused by listeria bacteria, which may also cause meningitis. Listeriosis increases the risk of miscarriage, stillbirth and premature delivery.
• Compromised immune system. AIDS, alcoholism, diabetes, use of immunosuppressant drugs and other factors that affect your immune system also make you more susceptible to meningitis. Having your spleen removed also increases your risk, and anyone without a spleen should get vaccinated to minimize that risk.