Haemophilus influenzae type B disease at 11 pediatric centres, 1996-1997.

Prior to the introduction of vaccines, Haemophilus influenzae type b (Hib) was the most important bacterial pathogen in early childhood, responsible for the majority of cases of meningitis and epiglottitis and contributing to the burden of cases of bacteremia, septic arthritis, pneumonia, and pericarditis . Beginning in 1992, all provinces and territories routinely immunized infants 2 months of age with the newer, more effective PRP-conjugate vaccines. The Canadian Pediatric Society's Immunization Monitoring Program, Active (IMPACT) previously documented the remarkable decline in Hib cases at participating centres through 1995. This report examines cases of Hib infection seen at IMPACT centres in 1996 and 1997.