Active surveillance was conducted by the 12 centers of the Canadian Immunization Monitoring Program, Active from 2000-2007 in children 16 years of age and younger to determine the influence of 7-valent pneumococcal conjugate immunization programs on the prevalence, serotype and antibiotic resistance patterns of invasive pneumococcal disease (IPD) caused by Streptococcus pneumoniae. The absolute number of reported IPD cases decreased 48% (p