Bacterial causes - These micro-organisms cause the most severe forms of meningitis. Common bacteria that cause meningitis include Streptococcus Pneumoniae, Nieserria Meningitidis, Listeria Monocytogenes and Staphylococcus Aureus.
A special kind of bacteria known as Mycobacteria also cause meningitis. The most common of the Mycobacteria is Mycobacterium tuberculosis which causes Tuberculous meningitis.
Viral Causes - Viral causes of meningitis include Entero-viruses, Epstein-Barr virus, Arbovirus, Herpes viruses, Cyto-megalovirus, and Varicella-zoster virus.
Other causes - These include micro-organisms like Fungi and Rickettsia, and other causes like chemical compounds, vaccinations and malignancies.
Answered - March, 2007