Contributor: Gordon K. Klintworth
Meningitis may be suppurative [meningitis - suppurative] or non-suppurative.  Most cases of  meningitis are caused by microorganisms. The main offenders are bacteria (Escherichia coli, Haemophilus influenzae, Neisseria meningitidis,  Streptococcus pneumoniae, Mycobacterium tuberculosis, Treponema pallidum), but viruses (enteroviruses [including coxsackievirus B and mumps virus, lymphocytic choriomeningitis virus, Epstein-Barr virus, and human herpesvirus 1], fungi, and amebae (Naegleria and Acanthamoeba) are responsible for some cases.