title: Pneumococcal resistance and serotype 19A in Pittsburgh-area children with acute otitis media before and after introduction of 7-valent pneumococcal polysaccharide vaccine.
abstract: METHODS
  Before and after introduction of pneumococcal conjugate vaccine (PCV7), the authors obtained nasopharyngeal (NP) specimens from 3 groups of children aged 6 to 23 months with acute otitis media (AOM): group 1 (pre-PCV7), group 2 (early post-PCV7), and group 3 (late post-PCV7).
  
  
  RESULTS
  Of the Streptococcus pneumoniae isolates, the proportion that were vaccine serotypes (VTs) declined progressively (60.4% vs 48.6% vs 5.2% in groups 1, 2, and 3, respectively; P < .001). Concurrently, increases occurred in the proportion of penicillin-nonsusceptible isolates (minimum inhibitory concentration >0.1 µg/mL; 26.7% vs 37.8% vs. 38.5%; P = .12); the proportion of isolates that were serotype 19A (4.0% vs 0% vs 25.9%; P < .001); and the proportion of 19A isolates that were penicillin-nonsusceptible (0% in group 1, 68.6% in group 3; P = .004).
  
  
  CONCLUSIONS
  Shifts in pneumococcal serotype distribution and increases in penicillin nonsusceptibility among pneumococcal isolates from children with AOM underscore the need for continuing bacteriological surveillance for future vaccine development.
authors.affiliation: Division of General Academic Pediatrics, Children’s Hospital of Pittsburgh of UPMC, 4401 Penn Ave., Pittsburgh, PA 15201, USA. hoberman@chp.edu
authors.forename: Alejandro
authors.initials: A
authors.lastname: Hoberman
authors.forename: Jack L
authors.initials: JL
authors.lastname: Paradise
authors.forename: Nader
authors.initials: N
authors.lastname: Shaikh
authors.forename: David P
authors.initials: DP
authors.lastname: Greenberg
authors.forename: Diana H
authors.initials: DH
authors.lastname: Kearney
authors.forename: D Kathleen
authors.initials: DK
authors.lastname: Colborn
authors.forename: Howard E
authors.initials: HE
authors.lastname: Rockette
authors.forename: Marcia
authors.initials: M
authors.lastname: Kurs-Lasky
authors.forename: M Catherine
authors.initials: MC
authors.lastname: McEllistrem
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Zoffel
authors.forename: Tracy L
authors.initials: TL
authors.lastname: Balentine
authors.forename: Karen A
authors.initials: KA
authors.lastname: Barbadora
authors.forename: Ellen R
authors.initials: ER
authors.lastname: Wald
mesh_terms: D000208:Acute Disease; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009305:Nasopharynx / Q000382:microbiology; D010033:Otitis Media / Q000276:immunology / Q000382:microbiology*; D011008:Pneumococcal Infections / Q000382:microbiology / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000008:administration & dosage / Q000276:immunology*; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification* / Q000302:isolation & purification*; D014611:Vaccination
chemical_list: D022242:Pneumococcal Vaccines