title: Bacterial prevalence and antimicrobial prescribing trends for acute respiratory tract infections.
abstract: OBJECTIVE
  Antimicrobials are frequently prescribed for acute respiratory tract infections (ARTI), although many are viral. We aimed to determine bacterial prevalence rates for 5 common childhood ARTI - acute otitis media (AOM), sinusitis, bronchitis, upper respiratory tract infection, and pharyngitis- and to compare these rates to nationally representative antimicrobial prescription rates for these ARTI.
  
  
  METHODS
  We performed (1) a meta-analysis of English language pediatric studies published between 2000 and 2011 in Medline, Embase, and the Cochrane library to determine ARTI bacterial prevalence rates; and (2) a retrospective cohort analysis of children age <18 years evaluated in ambulatory clinics sampled by the 2000-2010 National Ambulatory Medical Care Survey (NAMCS) to determine estimated US ARTI antimicrobial prescribing rates.
  
  
  RESULTS
  From the meta-analysis, the AOM bacterial prevalence was 64.7% (95% confidence interval [CI], 50.5%-77.7%); Streptococcus pyogenes prevalence during pharyngitis was 20.2% (95% CI, 15.9%-25.2%). No URI or bronchitis studies met inclusion criteria, and 1 sinusitis study met inclusion criteria, identifying bacteria in 78% of subjects. Based on these condition-specific bacterial prevalence rates, the expected antimicrobial rescribing rate for ARTI overall was 27.4% (95% CI, 26.5%-28.3%). However, antimicrobial agents were prescribed in NAMCS during 56.9% (95% CI, 50.8%-63.1%) of ARTI encounters, representing an estimated 11.4 million potentially preventable antimicrobial prescriptions annually.
  
  
  CONCLUSIONS
  An estimated 27.4% of US children who have ARTI have bacterial illness in the post-pneumococcal conjugate vaccine era. Antimicrobials are prescribed almost twice as often as expected during outpatient ARTI visits, representing an important target for ongoing antimicrobial stewardship interventions.
authors.affiliation: Divisions of Infectious Diseases and Centers for Clinical and Translational Research and matthew.kronman@seattlechildrens.org.
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Kronman
authors.affiliation: General Pediatrics, Department of Pediatrics, University of Washington, Seattle, Washington; and Child Health, Behavior, and Development, Seattle Children's Hospital Research Institute, Seattle, Washington.
authors.forename: Chuan
authors.initials: C
authors.lastname: Zhou
authors.affiliation: General Pediatrics, Department of Pediatrics, University of Washington, Seattle, Washington; and Child Health, Behavior, and Development, Seattle Children's Hospital Research Institute, Seattle, Washington.
authors.forename: Rita
authors.initials: R
authors.lastname: Mangione-Smith
mesh_terms: D000553:Ambulatory Care / Q000379:methods / Q000639:trends*; D000890:Anti-Infective Agents / Q000627:therapeutic use*; D002648:Child; D011307:Drug Prescriptions; D006801:Humans; D015995:Prevalence; D012141:Respiratory Tract Infections / Q000188:drug therapy* / Q000453:epidemiology* / Q000382:microbiology
chemical_list: D000890:Anti-Infective Agents
keywords: infectious diseases epidemiology; otitis media