256. Molecular Epidemiology of Pneumococcal Infections in Adults and Children from the Kansas City Area between 2010 and 2013
Session: Poster Abstract Session: Diagnostics: Typing and Sequencing
Thursday, October 8, 2015
Room: Poster Hall
  • S pneumo PFGE KC.pdf (488.0 kB)
  • Background: Pneumococcal infections cause morbidity and mortality in young children and older adults. Implementation of the pneumococcal conjugate vaccines, PCV7 and PCV13, substantially reduced invasive pneumococcal disease (IPD) for these groups.  However, the seroepidemiology of pneumococcal infections has been changing, with the emergence of nonvaccine serotype disease.

    Methods: We examined the molecular epidemiology of the most common serotypes among children and adults cared for at two medical centers in the Kansas City region in 2010-2013. Streptococcus pneumoniaeisolates from children with invasive and noninvasive disease and adults with IPD were serotyped using type-specific antisera and observation of the Quellung reaction. The most frequent serotypes shared among children and adults were selected for pulsed-field gel electrophoresis (PFGE) analysis.

    Results: A total of 379 (79 adult and 318 pediatric) S. pneumoniaeisolates were serotyped. PFGE analysis was conducted on 147 isolates of the most common serotypes shared among children and adults. PCV13-related isolates included serotypes/serogroups 3 (N=20), 7 (N=26), 19A (N=29), and 23 (N=13). Analyzed nonvaccine serotypes/serogroups were 15 (N=20), 22 (N=11), 33 (N=15), and 35 (N=13). Phylogenetic analysis revealed 20 clusters with 86% or greater genetic relatedness. Serotypes/serogroups 3, 7, 22, 33, and 35 formed individual closely related clusters that comprised 85% or more of their representative isolates. In contrast, serotypes/serogroups 15, 23, and 19A were more genetically diverse.

    Conclusion: Although nonvaccine serotype pneumococcal disease has emerged, PCV13-related pneumococcal disease persists. In the Kansas City region, pneumococcal isolates within serotypes/serogroups 3, 7, 22, 33, and 35 are genetically closely related. With the changing seroepidemiology of pneumococcal disease, continued surveillance is needed to learn whether PCV13-induced antibody pressure may lead to further serotype shifts or changing epitopes in existing serotypes.

    Douglas Swanson, MD1, Christopher Harrison, M.D., FSHEA, FPIDS2, Fernando Merino, MD3, Erin Atwood, BS4, Rebecca Horvat, PhD5, Maria J Tort, PhD6, Angee Mcdaniel, PharmD7, Anne James, BS8 and Richard Goering, Ph.D.8, (1)Children's Mercy Hospital & UMKC School of Medicine, Kansas City, MO, (2)Pediatrics, Children's Mercy Hospitals and Clinics, Kansas City, MO, (3)Infectious Diseases, University of Kansas Medical Center, Kansas City, KS, (4)University of Kansas School of Medicine, Kansas City, KS, (5)Pathology and Laboratory Medicine, University of Kansas, Kansas City, KS, (6)Pfizer Inc, Collegeville, PA, (7)Pfizer, Inc., Collegeville, PA, (8)Medical Microbiology and Immunology, Creighton University School of Medicine, Omaha, NE


    D. Swanson, Pfizer Inc: Grant Investigator , Research grant

    C. Harrison, Pfizer: Grant Investigator , Research support
    Actavis: Grant Investigator , Research grant
    GSK: Grant Investigator , Research grant

    F. Merino, Pfizer: Grant Investigator , Research grant

    E. Atwood, None

    R. Horvat, IBT Laboratory: Consultant and Speaker's Bureau , Consulting fee

    M. J. Tort, Pfizer: Employee , Salary

    A. Mcdaniel, Pfizer: Employee , Salary

    A. James, None

    R. Goering, None

    Findings in the abstracts are embargoed until 12:01 a.m. PDT, Wednesday Oct. 7th with the exception of research findings presented at the IDWeek press conferences.