Bacterial meningitis can occur at any age. However, it is more common among infants, children and young adults. It is also more common in the elderly people. According to WHO (Cited in Ramakrishnana et al, 48) "two thirds of meningitis deaths in low-income
Several species of bacteria cause meningitis and affectation with a particular species depends on the host and the setting. Community-acquired meningitis is usually due to Neisseria meningitides Hemophilus influenzae type-B or pneumococcus species (Ramakrishnana et al, 8). Some of these organisms are commensals in the upper respiratory tract of some healthy people (Tunkel, 1268). Listeria monocytogenes is another important cause of bacterial meningitis and it most commonly affects newborns, pregnant women, immunosuppressed and elderly population (Jacewicz, Merck Manual). Other bacteria causing meningitis include Escherichia coli, Hemophilus influenzae, Klebsiella, Pseudomonas, group-B streptococci and Staphylococcus aureus. E.coli and group-B streptococci occur in newborns (Jacewicz, Merck Manual). Pseudomonas infection is more common in the immunosupressed and Staphylococcus infection occurs following injury or surgery. (Jacewicz, Merck Manual) The highest fatality rate is seen in infection due to pneumococcus (Ramakrishnana et al, 48).
Certain individuals are at increased risk of developing bacterial meningitis because of their health condition. They are individuals suffering from chronic diseases like ischemic heart disease, chronic liver disease, end-stage renal failure, rheumatoid arthritis, endocrine dysfunction and immune disorders. Intake of immunosuppressants or glucocorticosteroids for immunosupression or cancer treatment also increases the risk of development of bacterial meningitis. Other risk factors include head injury,pneumococcal pneumonia, blood disorders like sickle cell anemia, splenectomy and chronic infections of the upper respiratory system.
Bacterial meningitis can