title: Pandemic H1N1 in children requiring intensive care in Australia and New Zealand during winter 2009.
abstract: OBJECTIVE
  To describe in detail the pediatric intensive care experience of influenza A, particularly pandemic H1N1-09, in Australia and New Zealand during the 2009 Southern Hemisphere winter and to compare the pediatric experience with that of adults.
  
  
  METHODS
  This was an inception-cohort study of all children who were admitted to intensive care with confirmed influenza A during winter 2009 at all general ICUs and PICUs in Australia and New Zealand.
  
  
  RESULTS
  From June 1 through August 31, 2009, 107 children (20.0 per million [95% confidence interval: 16.1-23.8]) with influenza A, including 83 (15.5 per million [95% confidence interval: 12.1-18.9]) with H1N1-09 were admitted to ICUs. Fifty-two percent (39 of 75) of children with H1N1-09 had 1 or more comorbidity, most commonly neurologic (20%). Most (48 of 83 [58%]) presented with pneumonia. Thirteen of 83 (16%) had neurologic presentations. Eighty percent of the children with H1N1-09 required ventilation. Mortality was lower than in adults: 6 of 83 (7%) vs 114 of 668 (17%) (P = .02). The median length of stay for children with H1N1-09 was 5 days. Children with H1N1-09 occupied 773 bed-days (147 per million children) and 5.8% of specialist PICU beds. Presentation with septic shock or after cardiac arrest and the presence of 1 or more comorbidities were risk factors for severe disease.
  
  
  CONCLUSIONS
  H1N1-09 caused a substantial burden on pediatric intensive care services in Australia and New Zealand. Compared with adults, children more commonly had nonrespiratory presentations and required ventilation more often but had a lower mortality rate.
authors.affiliation: Intensive Care Unit, Women's and Children's Hospital, Adelaide, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Yung
authors.forename: Anthony
authors.initials: A
authors.lastname: Slater
authors.forename: Marino
authors.initials: M
authors.lastname: Festa
authors.forename: Gary
authors.initials: G
authors.lastname: Williams
authors.forename: Simon
authors.initials: S
authors.lastname: Erickson
authors.forename: Ville
authors.initials: V
authors.lastname: Pettila
authors.forename: Janet
authors.initials: J
authors.lastname: Alexander
authors.forename: Belinda D
authors.initials: BD
authors.lastname: Howe
authors.forename: Lara S
authors.initials: LS
authors.lastname: Shekerdemian
mesh_terms: D000293:Adolescent; D000328:Adult; D001315:Australia / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003422:Critical Care; D005260:Female; D006801:Humans; D007223:Infant; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000453:epidemiology* / Q000628:therapy*; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D058873:Pandemics; D012621:Seasons