What are the Causes of Meningitis?
Meningitis is usually caused by bacteria or viral infections.
Viruses that can cause meningitis include:
- Enteroviruses (most common cause of viral infections)
- Herpes simplex virus type 2
- Varicella zoster virus
- Mumps virus
Bacterial infections commonly include infection by:
- Neisseria meningitidis
- Haemophilus influenza B
- Streptococcus pneumoniae
Other less common causes of meningitis include infections by fungi, amoeba and protozoa.
Non-infectious causes of meningitis include systemic diseases like SLE, sarcoidosis, polyarteritis nodosa, rheumatoid arthritis, toxins, certain medications and malignancies. Meningitis caused by non-infectious agents is called sterile meningitis because no microorganism is isolated from the spinal fluid.