There are many different bacteria and viruses that can cause meningitis. In most instances, it is more common for these viruses or bacteria to cause some other illness, such as an ear infection, pneumonia or other illness. It is not known why one individual develops meningitis when others exposed to the same virus or bacteria don't get as sick, or don't get sick at all.
Some forms of meningitis may pose a risk for causing serious
illness among close contacts. These include meningococcal
meningitis and, in some specific circumstances, H. influenzae type b meningitis. In these instances, there are preventative
actions that are recommended to protect close contacts.
The most common causes of bacterial meningitis:
Meningococcal disease is an illness caused by a bacteria called Neisseria meningitidis. It often causes meningitis but it can also cause bloodstream infections, pneumonia, joint infections, and other illness.
- Pneumococcal Disease (Streptococcus pneumoniae)
Pneumococcal disease is an infection caused by a type of bacteria called Streptococcus pneumoniae. It can cause pneumonia, bloodstream infections, or meningitis.
- Haemophilus influenzae, type b (Hib)
Until recently, Hib was one of the most common causes of bacterial infection in young children. Hib may cause a variety of diseases such as meningitis (inflammation of the coverings of the spinal column and brain), blood stream infections, pneumonia, arthritis and infections of other parts of the body.
- Bacterial Meningitis
CDC: Frequently asked questions about bacterial meningitis (Meningococcal disease, Neisseria meningitidis). Attention: Non-MDH link
The most common causes of viral meningitis is a group of viruses known as enteroviruses, which includes coxsackieviruses and echoviruses.
Provides frequently asked questions about viral meningitis, several viruses cause Meningitis. Attention: Non-MDH link
- Fungal Infections from Contaminated Medication (2012 Fungal Meningitis Outbreak)
Information about the 2012 nationwide investigation of fungal infections resulting from contaminated medications. The variety of fungal infections include an uncommon form of meningitis, which should not be confused with the viral or bacterial forms of the illness with which most people are familiar. Other kinds of infections include osteomyelitis (infection of the bone) and abscesses (infected fluid collections). These infections cannot be transmitted from person to person.