Definition of SBI An episode of SBI was defined as (A) the growth of a known pathogenic bacteria in one or more of cultures (bacteremia, meningitis, osteomyelitis, suppurative arthritis, urinary tract infection, bacterial enteritis, and pneumonia), (B) any disease commonly associated with bacterial pathogens including pneumonia, acute otitis media, suppurative arthritis, osteomyelitis, and soft-tissue infections (cellulitis, abscess, mastitis, and omphalitis). Pneumonia was defined as a new discrete infiltration on the chest film, which was confirmed by an attending pediatric radiologist with the presence of typical clinical signs and symptoms.