1955. Decrease in PCV13 Serotypes in Adults Hospitalized with Pneumococcal Pneumonia Over Time: Evidence of Herd Immunity Effects from Childhood Vaccination
Session: Poster Abstract Session: Clinical: Respiratory Track
Saturday, October 7, 2017
Room: Poster Hall CD
  • Jason LeBlanc Idweek 2017 CIRN_SOS_CAP UAD.pdf (602.6 kB)
  • Background: Pneumococcal community acquired pneumonia (CAP-Spn) and invasive pneumococcal disease (IPD) cause significant morbidity and mortality worldwide. Although childhood immunization programs have reduced the overall burden of pneumococcal disease in both children and adults (through herd immunity), there is insufficient data in Canada to inform immunization policy in immunocompetent adults. Given the routine use of 13-valent pneumococcal vaccine (PCV13) in childhood immunization programs in Canada since 2010, this study aimed to assess the impact of herd immunity on adults by determining the proportion of pneumococcal disease in hospitalized Canadian adults caused by PCV13 serotypes from 2011 to 2015.

    Methods: Active surveillance for CAP-Spn and IPD in hospitalized adults was performed in hospitals across five Canadian provinces from December 2010 to 2015. For serotyping, S. pneumoniae isolates recovered from sputum or blood culture were characterized by Quellung reaction, or CAP-Spn were serotyped using a PCV13-specific urine antigen detection (UAD-PCV13) assay.

    Results: From 2011 to 2015, 8.7% (326/3758) of adults hospitalized with CAP overall had a positive UAD-PCV13. When assessed individually by year, the proportion of PCV13 serotypes declined over this study period: 13.6% (44/323) in 2011, 11.9% (75/633) in 2012, 8.3% (99/1192) in 2013, 5.3% (50/944) in 2014, and 8.7% (58/666) in 2015. While the proportion of some PCV13 serotypes remained unchanged (i.e. serotype 3), others showed significant decreases over time (i.e. serotype 7F). Comparison of UAD-PCV13 data to S. pneumoniae isolates characterized by Quellung reactions is underway.

    Conclusion: In the five years following infant PCV13 immunization program implementation in Canada, S. pneumoniae serotypes contained in PCV13 remain an important cause of adults hospitalized with CAP. However, the proportion of PCV13 serotypes is decreasing over time. In order to inform recommendations on the use of PCV13 in adults, it will be important to maintain active surveillance for pneumococcal CAP and IPD to characterize the proportion of adult disease caused by PCV13 serotypes as the impact of herd protection conferred by childhood immunization programs is fully realized.

    Jason Leblanc, PhD1, May Elsherif, MD1, Lingyun Ye, MSc1, Donna Mackinnon-Cameron, MMath1, Todd Hatchette, MD FRCPC2, Amanda Lang, PhD1, Haley Gillis, BSc1, Irene Martin, BSc3, Ardith Ambrose, RN1, Melissa K Andrew, MD, PhD1, Guy Boivin, MD, MSc4, William R. Bowie, MD, FRCPC, FIDSA5, Karen Green, MSc, RN6, Jennie Johnstone, MD7, Mark Loeb, MD, MSc7, Anne Mccarthy, MD, MSc8, Allison Mcgeer, MD, MSc6, Makeda Semret, MD9, Sylvie Trottier, MD, PhD4, Louis Valiquette, MD, MSc, FRCPC10, Duncan Webster, MD11 and Shelly McNeil, MD, FRCPC, FIDSA1, (1)Canadian Center for Vaccinology, IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS, Canada, (2)Nova Scotia Health Authority, Dalhousie University, Halifax, NS, Canada, (3)National Microbiology Laboratory, Winnipeg, MB, Canada, (4)Centre Hospitalier Universitaire de Quebec, Quebec City, QC, Canada, (5)Division of Infectious Diseases, Department of Medicine, University of British Columbia, Vancouver, BC, Canada, (6)Mount Sinai Hospital, Toronto, ON, Canada, (7)McMaster University, Hamilton, ON, Canada, (8)The Ottawa Hospital, Ottawa, ON, Canada, (9)McGill University, Montreal, QC, Canada, (10)Microbiology and Infectious Disease, Université de Sherbrooke, Sherbrooke, QC, Canada, (11)Saint John Regional Hospital, Dalhousie University, Saint John, NB, Canada


    J. Leblanc, None

    M. Elsherif, Canadian Institutes of Health Research: Investigator , Research grant
    Public Health Agency of Canada: Investigator , Research grant
    GSK: Investigator , Research grant

    L. Ye, None

    D. Mackinnon-Cameron, None

    T. Hatchette, GSK: Grant Investigator , Grant recipient
    Pfizer: Grant Investigator , Grant recipient
    Abbvie: Speaker for a talk on biologics and risk of TB reactivation , Speaker honorarium

    A. Lang, None

    H. Gillis, None

    I. Martin, None

    A. Ambrose, None

    M. K. Andrew, GSK: Grant Investigator , Research grant
    Pfizer: Grant Investigator , Research grant
    Sanofi-Pasteur: Grant Investigator , Research grant

    G. Boivin, None

    W. R. Bowie, None

    K. Green, None

    J. Johnstone, None

    M. Loeb, None

    A. Mccarthy, None

    A. Mcgeer, Hoffman La Roche: Investigator , Research grant
    GSK: Investigator , Research grant
    Sanofi Pasteur: Investigator , Research grant

    M. Semret, GSK: Investigator , Research grant
    Pfizer: Investigator , Research grant

    S. Trottier, Canadian Institutes of Health Research: Investigator , Research grant

    L. Valiquette, GSK: Investigator , Research grant

    D. Webster, None

    S. McNeil, GSK: Contract Clinical Trials and Grant Investigator , Research grant
    Merck: Contract Clinical Trials and Speaker's Bureau , Speaker honorarium
    Novartis: Contract Clinical Trials , No personal renumeration
    Sanofi Pasteur: Contract Clinical Trials , No personal renumeration

    Findings in the abstracts are embargoed until 12:01 a.m. PDT, Wednesday Oct. 4th with the exception of research findings presented at the IDWeek press conferences.