Before the advent of antibiotics, the vast majority of bacterial meningitis cases, in those of all ages, proved fatal. Multiple Causes Meningitis is an inflammation of the meninges, the membranes surrounding the brain and spinal cord. Sometimes, perhaps even most of the time, the infectious agent is a virus. Those cases, however, are cause for far less concern than the ones resulting from bacterial infection. But it can be so mild that the patient doesn't even see a physician, and many cases are never diagnosed.
Bacterial meningitis is such a serious infection that it invariably comes to medical attention.
In fact, it ranks second to another organism. These two bacteria, together with the pneumococcus Streptococcus pneumoniae, account for four out of five cases of bacterial meningitis. Normally clear, the fluid is analyzed for the presence of bacteria and other evidence of infection. Samples of blood, urine, and respiratory secretions may also be taken. At least a week of treatment, and sometimes more, is needed.