What are the bacteria commonly responsible for bacterial meningitis?

Causative bacteria for meningitis varies according to age:
Neonates
  • Streptococcus agalactiae (Group B)
  • Gram –ve bacilli (e.g. E. coli, Klebsiella, Haemophilus influenzae)
  • Listeria Monocytogenes
Children 1-24 months
  • Neisseria Meningitidis
  • Streptococcus pneumonia
  • Streptococcus agalactiae (Group B)
  • Haemophilus influenza
Older Children & Younger Adults
  • Neisseria Meningitidis (22%)
  • Streptococcus pneumonia (18%)
  • Staphylococcus Aureus (10%)
Older Adults
  • As for younger adults
  • Listeria Monocytogenes
  • Aerobic gram-negative bacilli