title: Surveillance of hospitalizations with pandemic A(H1N1) 2009 influenza infection in Queensland, Australia.
abstract: OBJECTIVE
  To describe the demographic and clinical characteristics of patients hospitalized with pandemic A(H1N1) 2009 infection in Queensland, Australia between 25 May and 3 October 2009 and to examine the relationship between timing of antiviral treatment and severity of illness.
  
  
  METHODS
  Using data from the Queensland Health EpiLog information system, descriptive analysis and logistic regression modelling were used to describe and model factors which influence patient outcomes (death, admission to intensive care unit and/or special care unit). Data on patients admitted to hospital in Queensland with confirmed pandemic A(H1N1) 2009 infection were included in this analysis.
  
  
  RESULTS
  1236 patients with pandemic A(H1N1) 2009 infection were admitted to hospitals in Queensland during the study period. Of the total group: 15% were admitted to an intensive care unit or special care unit; 3% died; 34% were under the age of 18 years and 8% were 65 years of age or older; and 55% had at least one underlying medical condition. Among the 842 patients for whom data were available regarding the use of antiviral drugs, antiviral treatment was initiated in 737 (87.5%) patients, treatment commenced at a median of one day (range 1-33 days) after onset of illness. Admission to an intensive care unit or special care unit (ICU/SCU) or death was significantly associated with increased age, lack of timeliness of antiviral treatment, chronic renal disease and morbid obesity.
  
  
  CONCLUSIONS
  Early antiviral treatment was significantly associated with lower likelihood of ICU/SCU admission or death. Early antiviral treatment for influenza cases may therefore have important public health implications.
authors.affiliation: Communicable Diseases Branch, Queensland Health, Brisbane, Queensland, Australia . ; School of Public Health, Queensland University of Technology, Brisbane, Queensland, Australia .
authors.forename: Hai
authors.initials: H
authors.lastname: Phung
authors.forename: Frank
authors.initials: F
authors.lastname: Beard
authors.forename: Christine
authors.initials: C
authors.lastname: Selvey
authors.forename: Ranil
authors.initials: R
authors.lastname: Appuhamy
authors.forename: Frances
authors.initials: F
authors.lastname: Birrell
references.citation: CMAJ. 2010 Feb 23;182(3):257-64
references.pmid: 20093297
references.citation: MMWR Morb Mortal Wkly Rep. 2009 Jul 17;58(27):749-52
references.pmid: 19609249
references.citation: Euro Surveill. 2010 Jan 14;15(2):
references.pmid: 20085690
references.citation: N Engl J Med. 2009 Nov 12;361(20):1925-34
references.pmid: 19815860
references.citation: JAMA. 2009 Nov 4;302(17):1896-902
references.pmid: 19887665
references.citation: JAMA. 2009 Nov 4;302(17):1872-9
references.pmid: 19822627
references.citation: N Engl J Med. 2009 Dec 24;361(26):2507-17
references.pmid: 20007555
references.citation: CMAJ. 2010 Mar 9;182(4):349-55
references.pmid: 20159893
references.citation: Med J Aust. 2010 May 17;192(10):617-22
references.pmid: 20477746
references.citation: Euro Surveill. 2009 Aug 27;14(34):
references.pmid: 19712648
references.citation: PLoS One. 2010 Mar 15;5(3):e9694
references.pmid: 20300571
references.citation: Lancet. 2009 Aug 8;374(9688):451-8
references.pmid: 19643469
references.citation: Med J Aust. 2010 Jan 18;192(2):94-7
references.pmid: 20078411
references.citation: Stat Med. 1996 Feb 28;15(4):361-87
references.pmid: 8668867
references.citation: N Engl J Med. 2009 Nov 12;361(20):1935-44
references.pmid: 19815859
references.citation: Radiology. 1982 Apr;143(1):29-36
references.pmid: 7063747