Program Schedule

964
Seroepidemiology of Pediatric Pneumococcal Colonization and Infection Before and After  13-valent Pneumococcal Conjugate Vaccine (PCV13)

Session: Poster Abstract Session: Pediatric - Bacterial Studies
Friday, October 10, 2014
Room: The Pennsylvania Convention Center: IDExpo Hall BC

Background: Routine heptavalent pneumococcal conjugate vaccine (PCV7) use since 2000 changed serotype prevalence and antibiotic susceptibilities. In 2010, PCV13 added serotypes that emerged post-PCV7. We examined aspects of colonization, noninvasive disease, and invasive pneumococcal disease (IPD) in children during 3 years before and after PCV13 licensure.

Methods: To assess PCV13's impact, we analyzed clinical data and pneumococcal isolates from 2007 through 2013, excluding 2010 (transition year). This included demographic data, infection site, serotype by Quelling reaction and antimicrobial susceptibility.

Results: Overall, 709 pneumococcal isolates were serotyped. There was a marked decrease in pneumococcal cases following the introduction of PCV13. Of 453 isolates in 2007 through 2009 (pre-PCV13), 95 were colonizing, 216 noninvasive disease-related, and 142 IPD-related. Of 256 isolates in 2011 through 2013 (PCV13 era), 45 were colonizing (P=0.05), 134 noninvasive disease-related (P=0.03), and 77 IPD-related (P=0.007).  Predominant serotypes/serogroups were:

Pre-PCV13, 61% of IPD isolates were PCV13-related, whereas during the PCV13 era, 40% of IPD isolates were PCV13-related (P=0.023). The average age of children with IPD pre-PCV13 was 43.5 months (range 1 week to 15.3 years) and it was 52.7 months (range 1 week to 16 years) for children with IPD in the post-PCV13 era.  Central nervous system infections averaged 9.0 cases/year pre-PCV13, and 3.3 cases/year post-PCV13 (P=0.05). An underlying medical condition was present in 32% of children with invasive disease in the pre-PCV13 era, and 43% of children in the post-PCV13 era (P=0.14). Pre-PCV13, the distribution for highly susceptible, intermediate, and resistant organisms was 50.5%, 19.4%, and 30.1% respectively, whereas post-PCV13 the distribution was 69.4%, 20.5%, and 10.1% (P<0.01).

Conclusion: There were significantly fewer pneumococci isolated in the post-PCV13 era, especially for cases of IPD. However, a sizable proportion of isolates, particularly IPD isolates, remain PCV13-related.  There has been a considerable reduction in the proportion of penicillin-resistant isolated following the introduction of PCV13.

Douglas Swanson, MD1, Christopher Harrison, M.D.2, R. Scott Duncan, Ph.D.3, Chris Paap, Pharm D4 and Laura Puzniak, PhD, MPH4, (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, Children's Mercy Hospital, Kansas City, MO, (4)Pfizer Inc, Collegeville, PA

Disclosures:

D. Swanson, Pfizer: Grant Investigator, Grant recipient

C. Harrison, Pfizer: Investigator, Grant recipient
Forest Laboratories: Investigator, Grant recipient
GSK: Investigator, Grant recipient

R. S. Duncan, None

C. Paap, Pfizer inc: Employee and Shareholder, Salary

L. Puzniak, Pfizer: Employee, Salary

Findings in the abstracts are embargoed until 12:01 a.m. EDT, Oct. 8th with the exception of research findings presented at the IDWeek press conferences.

Sponsoring Societies:

© 2014, idweek.org. All Rights Reserved.

Follow IDWeek