There are actually three different meninges, which make up a layered covering. Spinal meningitis is not really a correct medical term, since meningitis always involves the meninges around the brain as well as those around the spinal cord, but it has been commonly used for years to refer to the particularly deadly forms of meningitis caused by bacteria. Meningitis, like inflammation in many organs, can be caused by viruses, bacteria, fungi, parasites, and noninfectious conditions. Parasites and fungi are rare causes of meningitis, predominately in people suffering from immune deficiency.
Noninfectious causes are also uncommon.
Viral meningitis is fairly common, can make someone quite sick, but is seldom deadly in adults with normal immune systems. It does not occur in epidemic forms, and transmission from an infected person to others is not a risk. Acute bacterial meningitis on the other hand is an extremely deadly disease, which before the antibiotic era probably killed everyone infected. The most common forms are seen in children and young adults and are caused by the bacteria H. influenzae, Strep. Pneumoniae, and Neisseria meningitidis.