Invasive Pneumococcal Infections in Canadian Children, 1998–2003 Implications for New Vaccination Programs

Abstract

Background: We conducted active surveillance for invasive pneumococcal disease to assess the serotype and antibiotic resistance patterns in Canada prior to universal infant immunization programs, in most provinces. Methods: Active surveillance was conducted by the 12 centres of the Canadian Paediatric Society's Immunization Monitoring Program, Active (IMPACT). This report includes children 16 years of age and younger with S. pneumoniae isolated from a normally sterile site, in 1998-2003.Results: During six years of surveillance, 1,868 eligible cases were reported. The 7-valent pneumococcal conjugate vaccine (PCV7) matched 79% of isolates, including 84% from 6-23 month olds and 80% from 2-5 year olds. The proportion of isolates matched by PCV7 significantly decreased over the surveillance period from 81% in 1998 to 73% in 2003 (p=0.005). The 23-valent polysaccharide vaccine (PPS) matched 90% of isolates from children 2 years or older.Penicillin non-susceptibility rate was stable at 16% of isolates. Cefotaxime/ceftriaxone resistance rate was 5% and limited to penicillin-resistant isolates. Serotypes found in PCV7 accounted for 89% of penicillin-resistant isolates (100% including cross-reacting types 6A and 19A). Conclusion:PCV7 matched three quarters of the isolates from young children as immunization programs began; therefore some program failures are inevitable. Children ≥5 years with predisposing conditions need the broader protection of 23-valent PPS vaccine and special attention from providers to ensure receipt. The rate of penicillin resistance remained steady over the last six years. The majority of isolates non-susceptible to penicillin are found in PCV7. MeSH terms: Pneumococcal infections; drug resistance; pneumococcal vaccinesLa traduction du résumé se trouve à la fin de l'article.

The burden of pneumococcal disease in children less than 5 years of age in Abu Dhabi, United Arab Emirates

“…To our knowledge, this is the only epidemiological study that addresses the incidence of pneumococcal disease in children under 5 years in the UAE. In North America, the reported incidence rates are 72/100 000 in southern California and 11.8-16.1 population in Canada 1213. In Europe, the rates are 42.1 in Great Britain, 24.2 in Finland, and 10.1 population in Germany 14–16.…”

“…In North America, the reported incidence rates are 72/100 000 in southern California and 11.8-16.1 population in Canada. 12 13 In Europe, the rates are 42.1 in Great Britain, 24.2 in Finland, and 10.1 population in Germany. 14 – 16 In Australia, it is 12.7.…”

Effectiveness of the standard and an alternative set of Streptococcus pneumoniae multi locus sequence typing primers

“…Evaluation of the standard and alternative MLST primers was carried out on five randomly selected isolates from strains collected provided by the Canadian Immunization Monitoring Program ACTive (IMPACT) [ 23 - 26 ]. Isolates were obtained from patients aged 0 – 16 presenting with invasive pneumococcal infection at tertiary care centres across Canada; diagnosis was confirmed by positive S. pneumoniae culture from normally sterile body fluid (blood/cerebrospinal fluid).…”

Commonly invasive serotypes ofStreptococcus pneumoniaetrigger a reduced innate immune response compared with serotypes rarely responsible for invasive infection

“…However, the prevalence with which the serotypes are recovered from patients with invasive disease varies considerably, presumably because some serotypes have a much greater propensity to cause invasive disease than others. International pneumococcal surveillance has demonstrated that 70–88% of invasive pneumococcal disease in young children was caused by serotypes now included in the seven‐valent protein‐conjugated vaccine formulation (4, 6B, 9V, 14, 18C, 19F, and 23F) (Henriques et al ., 2000; Hausdorff et al ., 2005; Bettinger et al ., 2007). This finding is consistent with the hypothesis that, regardless of ethnic and socioeconomic differences, ‘commonly invasive’ serotypes as a group have a high level of intrinsic virulence relative to other serotypes.…”