Invasive pneumococcal infections in Canadian children, 1991-1998: implications for new vaccination strategies. Canadian Paediatric Society/Laboratory Centre for Disease Control Immunization Monitoring Program, Active (IMPACT).
We reviewed 2040 consecutive cases of invasive pneumococcal infection that were seen at 11 pediatric centers across Canada during 1991-1998 to determine if such infections could be prevented by new conjugate vaccines. Isolates from 1528 cases were serotyped. Most cases (61.5%) occurred in patients aged >2 years. Underlying medical conditions were present in 23.2% of case patients. Serotypes in the 7-valent conjugate vaccine matched isolates as follows: 85.8% of tested isolates from children aged 6 months to 5 years, but significantly fewer isolates in younger and older children; 72.9% of isolates from non-healthy children, but 83.9% of isolates from previously healthy children; and 95.4% of isolates with high-level penicillin resistance, but only 72.7% of those with intermediate-level resistance. Significant natural variation in the proportion of isolates matching 7-valent vaccines occurred from year to year and among centers. New conjugate vaccines have great potential but their effectiveness and limitations require ongoing study.
Scheifele
D
D
Canadian Paediatric Society, Ottawa, Ontario, Canada. dscheifele@cw.bc.ca
Halperin
S
S
Pelletier
L
L
Talbot
J
J
D016470:Bacteremia / Q000145:classification / Q000382:microbiology / Q000517:prevention & control; D002170:Canada; D002648:Child; D002675:Child, Preschool; D005260:Female; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007223:Infant; D008297:Male; D008586:Meningitis, Pneumococcal / Q000145:classification / Q000382:microbiology / Q000517:prevention & control; D022401:Meningococcal Vaccines / Q000276:immunology*; D011008:Pneumococcal Infections / Q000145:classification / Q000382:microbiology / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000276:immunology*; D011018:Pneumonia, Pneumococcal / Q000145:classification / Q000382:microbiology / Q000517:prevention & control; D013296:Streptococcus pneumoniae / Q000145:classification / Q000302:isolation & purification; D014611:Vaccination / Q000379:methods; D018074:Vaccines, Conjugate / Q000276:immunology*
D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D022401:Meningococcal Vaccines; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate