668. Eradication of 7-valent Pneumococcal Conjugate Vaccine (PCV7) Serotypes Causing Invasive Pneumococcal Disease (IPD) in Young Children in Calgary, Canada
Session: Poster Abstract Session: Pneumococcal Vaccines
Friday, October 21, 2011
Room: Poster Hall B1
Background: The seven-valent pneumococcal conjugate vaccine (PCV7 [Prevnar, Pfizer Canada Inc]) was licensed in Canada in 2001. Publicly funded universal infant vaccination began in the province of Alberta in 2002. This study describes the impact of PCV7 on vaccine serotype invasive pneumococcal disease (IPD) at all ages in our population, nearly a decade after the introduction of PCV7.

Methods: Prospective, population-based surveillance of all cases of IPD (defined by positive sterile site cultures) was conducted from Jan 1998 to Dec 2010 in Calgary, Alberta (population increased from 820,000 to 1,100,000 during study period). Demographic and clinical data were collected. All viable isolates were saved and serotyped.

Results: There were 1,462 IPD cases over the 13-year period. Comparison of the incidence of PCV7 serotype IPD in the pre-vaccine period (1998-2001) to the late post-vaccine period (2007-2010) showed declines in all age groups: 0-5 mos (100%, p=0.07); 6-23 mos (98%. p<0.001); 2-4 yrs (97%, p<0.001); 5-15 yrs (100%, p<0.001); 16-64 yrs (73%, p<0.001); 65-84 yrs (90%, p<0.001); and 85 years and older (100%, p<0.001). In 2008, 2009 and 2010 there were no cases of PCV7 serotype IPD in children under 2 years of age. The incidence of non-PCV7 IPD increased in all age groups; most predominantly serotype 19A in children, and serotypes 5 and 19A in adults.

Conclusion: PCV7 serotype IPD has been eradicated in children less than 2 years of age in Calgary, and nearly eradicated in all other age groups. Serotype 19A IPD is the most common serotype at all ages before the introduction of a new expanded valence conjugate vaccine.

Subject Category: C. Clinical studies of bacterial infections and antibacterials including sexually transmitted diseases and mycobacterial infections (surveys, epidemiology, and clinical trials)

Jenine Leal, MSc, Pediatrics, University of Calgary, Calgary, AB, Canada, Otto Vanderkooi, MD, Pediatrics, Microbiology and Infectious Diseases and Pathology and Laboratory Medicine, University of Calgary, Calgary, AB, Canada, Deirdre Church, MD PhD, Microbiology, Calgary Laboratory Services, Calgary, AB, Canada; Pathology and Laboratory Medicine and Medicine, University of Calgary, Calgary, AB, Canada, Judy MacDonald, MD, Community Health Sciences, University of Calgary, Calgary, AB, Canada; Alberta Health Services - Calgary, Calgary, AB, Canada, David Scheifele, MD, Pediatrics, University of British Columbia, Vancouver, BC, Canada; Vaccine Evaluation Center, Child and Family Research Institute, Vancouver, BC, Canada and James D. Kellner, MD, Pediatrics and Microbiology and Infectious Diseases, University of Calgary, Calgary, AB, Canada; Pediatrics, Alberta Health Services - Calgary, Calgary, AB, Canada


J. Leal, None

O. Vanderkooi, Pfizer: Investigator, Research grant

D. Church, None

J. MacDonald, Pfizer: Investigator, Research grant

D. Scheifele, Pfizer: Investigator, Research grant

J. D. Kellner, Pfizer: Grant Investigator, Research grant

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