title: The epidemiology of pediatric patients seen at the Children's Hospital of Oklahoma with laboratory confirmed influenza in 2009.
abstract: BACKGROUND
  In 2009, a new strain of influenza A, subtype H1N1, infected otherwise healthy children with increased rate of hospitalization.
  
  
  OBJECTIVE
  To document the type of influenza infection, identify those pediatric patients at risk for complications, compare those patients requiring hospital admission to those discharged, and examine the use of antiviral/antibiotic medications.
  
  
  METHODS
  We conducted a retrospective chart review of patients 0-18 years, in 2009 that tested positive at Children's Hospital for influenza. Type of influenza, initial presentation, secondary complications, underlying co-morbidities, hospitalization, death, antiviral and antibiotic prescribing practices were recorded.
  
  
  RESULTS
  Two hundred and eighty-seven patients tested positive. Two hundred and twelve were influenza A, H1N1 subtype, 55 were Influenza A, not subtyped and 20 were influenza B. One hundred and twenty-eight of our study patients were hospitalized (44%). One hundred and three patients were positive for H1N1, for a hospitalization rate of 47%, Fifteen percent of the study population required Intensive care support. Caucasian patients and those having chronic medical conditions were more likely to require hospitalization. Early antiviral therapy was associated with a better outcome.
  
  
  CONCLUSIONS
  The majority of children with influenza in 2009 had the novel H1N1 strain. Almost half of study patients were hospitalized. Patients with underlying medical problems were more likely to be hospitalized. The majority of hospitalized patients had good outcomes.
authors.forename: Amanda Lynn
authors.initials: AL
authors.lastname: Bogie
authors.forename: Katherine
authors.initials: K
authors.lastname: Grant
authors.forename: Gene
authors.initials: G
authors.lastname: Hallford
authors.forename: Michael
authors.initials: M
authors.lastname: Anderson
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006776:Hospitals, Pediatric; D006801:Humans; D007223:Infant; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification*; D009981:Influenza B virus / Q000302:isolation & purification*; D007251:Influenza, Human / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology* / Q000401:mortality / Q000503:physiopathology; D008297:Male; D008485:Medical Audit; D009825:Oklahoma / Q000453:epidemiology; D012189:Retrospective Studies