443. Age-specific Reductions in the Proportion of Pediatric Invasive Pneumococcal Disease Caused by Serotype 19A and Other PCV13 Serotypes, 2008-2011
Session: Poster Abstract Session: Pneumococcal Vaccine in Children and Adults
Thursday, October 3, 2013
Room: The Moscone Center: Poster Hall C
Posters
  • 443__IDWPOSTER.pdf (211.4 kB)
  • Background:

    Few studies describe age-specific reductions in the proportion of pediatric invasive pneumococcal disease (IPD) caused by serotype 19A and other 13-valent pneumococcal conjugate vaccine (PCV13) serotypes.

    Methods:

    Using ecological data, we determined age-specific proportions of IPD caused by serotype 19A and the other serotypes included in PCV13 before (2008-2009) and after (2010-2011) PCV13 introduction.  IPD cases were identified from 8 children’s hospitals (US Pediatric Multicenter Pneumococcal Surveillance Group).  We compared baseline rates (2008-2009) to the most recent data (2011) using Chi-square tests. 

    Results:

    Among those aged 0-17 years, the proportion of IPD caused by serotype 19A in 2008-2009, 2010, and 2011 was 37%, 37%, and 28%. The proportion of IPD caused by the other 12 (non-19A) PCV13 serotypes for those same years was 66%, 62%, and 48%.  However, reductions were not consistent across age group.  Specifically, for those aged 0-1 year, there was a 44% (p<.01) relative reduction in the proportion of IPD caused by PCV13 serotypes, where as the percentage among those aged 2-17 was only 17% (p=.12) (p for interaction =.05).  The difference in these two age groups was driven largely by the difference in reduction of the proportion of IPD caused by serotype 19A.  While there was a 36% relative decrease (p<.01) in the proportion of IPD caused by serotype 19A among those aged 0-1, there was no change among those aged 2-17 (p=.87) (p for interaction =.04).  For the other non-19A PCV13 serotypes, the relative percent reduction (32%, p=.04) did not depend on age group (p for interaction =.86).  Only 2 children aged ≥11 had received PCV13.  The proportion of children with IPD that had underlying comorbidities increased significantly with increasing age.  For ages <1 year, 1-2, 3-5, and 6-17 years, respectively, 27%, 32%, 45%, and 60% of children with IPD had comorbid disease (p-trend<.001).

    Conclusion:

    Children aged 0-1 year had significant reductions in both 19A and in the other 12 (non-19A) PCV13 serotypes from 2008 through 2011.  Children aged 2-17, however, had a reduction in non-19A PCV13 serotypes, but not 19A.  Reasons for this could include lack of early indirect effect, virulence of 19A, and more comorbid disease and low PCV13 utilization in older children.

    John M. Mclaughlin, PhD, MSPH1, Sheldon L. Kaplan, MD, FIDSA2, Kristina G. Hulten, PhD2, William J. Barson, MD3, Philana L. Lin, MD, MSc4, Jose R. Romero, MD5, John S. Bradley, MD, FIDSA6, Tina Tan, MD, FIDSA7, Jill A. Hoffman, MD8, Laurence B. Givner, MD9, Stephen Kagan, MD, FACP1, Charles A. Thompson, M.D.1 and Edward O. Mason, PhD2, (1)Pfizer Specialty Care Medicines Development Group, Collegeville, PA, (2)Baylor College of Medicine and Texas Children's Hospital, Houston, TX, (3)Nationwide Children's Hospital and The Ohio State University College of Medicine, Columbus, OH, (4)Children's Hospital of Pittsburgh, Pittsburgh, PA, (5)University of Arkansas for Medical Sciences, Little Rock, AR, (6)Rady Children's Hospital - San Diego, San Diego, CA, (7)Northwestern University Feinberg School of Medicine, Chicago, IL, (8)Children's Hospital, Los Angeles, Los Angeles, CA, (9)Wake Forest University School of Medicine, Winston-Salem, NC

    Disclosures:

    J. M. Mclaughlin, Pfizer, Inc.: Employee and Shareholder, Salary

    S. L. Kaplan, Pfizer, Inc.: Grant Investigator, Research support

    K. G. Hulten, Pfizer, Inc.: Grant Investigator, Research support

    W. J. Barson, None

    P. L. Lin, None

    J. R. Romero, None

    J. S. Bradley, None

    T. Tan, None

    J. A. Hoffman, None

    L. B. Givner, None

    S. Kagan, Pfizer, Inc.: Employee and Shareholder, Salary

    C. A. Thompson, Pfizer, Inc.: Employee and Shareholder, Salary

    E. O. Mason, Pfizer, Inc.: Grant Investigator, Research support

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