title: Near-elimination of otitis media caused by 13-valent pneumococcal conjugate vaccine (PCV) serotypes in southern Israel shortly after sequential introduction of 7-valent/13-valent PCV.
abstract: BACKGROUND
  Otitis media (OM) is common in early childhood. Streptococcus pneumoniae caused approximately 30%-60% of episodes before the pneumococcal conjugate vaccine (PCV) era. The 7-valent PCV (PCV7) was introduced to the Israeli National Immunization Plan in July 2009, and was gradually replaced by the 13-valent PCV (PCV13) starting in November 2010. We aimed at assessing the impact of PCV7/PCV13 sequential introduction on pneumococcal and overall OM necessitating middle ear fluid culture in children aged <2 years in southern Israel.
  
  
  METHODS
  This was a prospective, population-based, active surveillance. Our medical center is the only one in the region, enabling incidence calculation. All pneumococcal episodes submitted for culture between July 2004 and June 2013 were included. Three subperiods were defined: pre-PCV, PCV7, and PCV13.
  
  
  RESULTS
  Overall, 6122 OM episodes were recorded, and 1893 were pneumococcal. Compared with the pre-PCV period, OM caused by PCV7 plus serotype 6A and the 5 additional PCV13 serotypes (5VT : 1, 3, 5, 7F, 19A) decreased by 96% and 85%, respectively (incidence rate ratios [IRRs], 0.04 [95% confidence interval {CI}, .02-.08] and 0.15 [95% CI, .07-.30], respectively) in a 2-step pattern: In the PCV7 period, only OM caused by PCV7 + 6A serotypes was decreased; in the PCV13 period, 5VT OM rates decreased, along with an additional PCV7 + 6A OM reduction. A nonsignificant increase in non-PCV13 serotype OM was observed (IRR, 1.07 [95% CI, .72-1.58]). In total, 77% and 60% reductions of all-pneumococcal and all-cause OM incidences, respectively, were observed.
  
  
  CONCLUSIONS
  A substantial 2-step reduction of pneumococcal OM rates, with near-elimination of PCV13 disease, was observed shortly after PCV7/PCV13 introduction.
authors.affiliation: Pediatric Infectious Disease Unit The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Shalom
authors.initials: S
authors.lastname: Ben-Shimol
authors.affiliation: Pediatric Infectious Disease Unit The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Noga
authors.initials: N
authors.lastname: Givon-Lavi
authors.affiliation: Pediatric Infectious Disease Unit The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Eugene
authors.initials: E
authors.lastname: Leibovitz
authors.affiliation: Department of Otolaryngology, Soroka University Medical Center The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Simon
authors.initials: S
authors.lastname: Raiz
authors.affiliation: Pediatric Infectious Disease Unit The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: David
authors.initials: D
authors.lastname: Greenberg
authors.affiliation: Pediatric Infectious Disease Unit The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Ron
authors.initials: R
authors.lastname: Dagan
mesh_terms: D006801:Humans; D007557:Israel; D010033:Otitis Media / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000009:adverse effects / Q000627:therapeutic use*; D011446:Prospective Studies; D013296:Streptococcus pneumoniae / Q000276:immunology / Q000472:pathogenicity; D018074:Vaccines, Conjugate / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: C538862:13-valent pneumococcal vaccine; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate
keywords: Streptococcus pneumonia; children; otitis media; pneumococcal conjugate vaccine; surveillance