Most common organism causing meningitis in a 1 year old child is:
The common organisms causing acute bacterial meningitis in the neonatal period are E.coli, Streptococcus pneumonia, Salmonella species, Pseudomonas aeruoginosa, Streptococcus fecalis and Staphylococcus aureus. Ref: Ghai Essential Pediatris - 6th Edition, Page 517; Nelson 17th Edition, Page 2308.
Streptococcus pneumoniae
H. influenza
Listeria
Neisseria meningitidis