BACTERIAL MENINGITIS

Neisseria meningitidis ,Streptococcus pneumoniae and Haemophilus influenzae (type b) constitute more than 75% of all cases of bacterial meningitis and 90%of bacterial meningitis in children .
The less common bacterial causes of meningitis including staphylococci ,enteric bacteria, group B streptococci and Listeria which occurring in persons with specific susceptibilities such as neonates and patients with impaired immunity and those with head injury.
Meningococcal meningitis or cerebrospinal fever is a bacterial form of meningitis which is a serious infection of the thin lining that surrounds the brain and spinal cord. It is an acute communicable disease caused by N. meningitidis .
This disease characterized by headache ,vomiting ,stiff
neck and photophobia with petechial rash.
Case fatality rate exceeded 50% but with treatment it
decrease to 8% to 15% .
In Europe and north America the incidence is higher during winter and spring while in Africa it is higher among dry season. Infants have higher risk of disease and incidence decrease after infancy but in increase in adolescence and young adults. In some countries male affected more than female.Immune deficiency such as asplenia, overcrowding, low socio-economic status, exposure to tobacco and concurrent upper respiratory tract infections increase the risk of disease.
The extended meningitis belt of sub-Saharan Africa, stretching from Senegal in the west to Ethiopia in the east (26 countries), has the highest rates of the disease.