title: Effect of fever on hospital presentation, diagnosis, and treatment in patients with H1N1/09 influenza.
abstract: OBJECTIVE
  Fever is typically considered part of the influenza-like illness in hemagglutinin type 1 and neuraminidase type 1 (H1N1/09) influenza. We assessed the proportion of patients that did not have fever as part of their illness prior to hospital presentation. We assessed the role of fever on the delay in hospital presentation, diagnosis, and treatment of these patients.
  
  
  METHODS
  We performed a retrospective analysis of all hospitalized adult patients with laboratory-confirmed pandemic H1N1/09 at a tertiary care center in the United States from June 1 to December 31, 2009.
  
  
  RESULTS
  Fifty-six of 135 study patients (42%) had no fever; 31 (23%) required intensive care unit (ICU) admission, and 9 (7%) died. Those without fever had higher Charlson index (P = 0.01), significantly longer time to hospital presentation (median 4 vs 2 days, P < 0.001), longer time to treatment since the onset of illness (median 5 vs 2 days, P = 0.001), and were more frequently in an ICU (P = 0.01). After adjustment for age (<40 vs ≥40) and Charlson index (0, 1-2, ≥3), patients without fever had significantly increased likelihood of late hospital presentation (>2 days from the onset of illness) (P = 0.001) and also had increased likelihood of ICU stay (P = 0.05).
  
  
  CONCLUSIONS
  Forty-two percent of patients with laboratory-confirmed H1N1/09 did not have fever as part of their illness prior to hospital presentation. Patients without fever had delayed presentation to the hospital and thus experienced delayed treatment.
authors.affiliation: Division of Infectious Diseases, University of Cincinnati, Cincinnati, Ohio, USA. madhuri.sopirala@uchealth.com
authors.forename: Madhuri M
authors.initials: MM
authors.lastname: Sopirala
authors.forename: Douglas M
authors.initials: DM
authors.lastname: Haas
authors.forename: Naeem A
authors.initials: NA
authors.lastname: Ali
authors.forename: Julie E
authors.initials: JE
authors.lastname: Mangino
authors.forename: Xueliang
authors.initials: X
authors.lastname: Pan
authors.forename: Abigail Norris
authors.initials: AN
authors.lastname: Turner
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000008:administration & dosage / Q000627:therapeutic use; D015897:Comorbidity; D005260:Female; D005334:Fever; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification; D007251:Influenza, Human / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology / Q000821:virology*; D007362:Intensive Care Units / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D009820:Ohio; D053139:Oseltamivir / Q000008:administration & dosage / Q000627:therapeutic use*; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data; D010343:Patient Admission / Q000706:statistics & numerical data; D012189:Retrospective Studies; D062606:Tertiary Care Centers / Q000706:statistics & numerical data; D013997:Time Factors; D014481:United States
chemical_list: D000998:Antiviral Agents; D053139:Oseltamivir