title: Risk factors associated with fatal influenza, Romania, October 2009-May 2011.
abstract: BACKGROUND
  Limited data are available from Central and Eastern Europe on risk factors for severe complications of influenza. Such data are essential to prioritize prevention and treatment resources and to adapt influenza vaccination recommendations.
  
  
  OBJECTIVE
  To use sentinel surveillance data to identify risk factors for fatal outcomes among hospitalized patients with severe acute respiratory infections (SARI) and among hospitalized patients with laboratory-confirmed influenza.
  
  
  METHODS
  Retrospective analysis of case-based surveillance data collected from sentinel hospitals in Romania during the 2009/2010 and 2010/2011 winter influenza seasons was performed to evaluate risk factors for fatal outcomes using multivariate logistic regression.
  
  
  RESULTS
  During 2009/2010 and 2010/2011, sentinel hospitals reported 661 SARI patients of which 230 (35%) tested positive for influenza. In the multivariate analyses, infection with influenza A(H1N1)pdm09 was the strongest risk factor for death among hospitalized SARI patients (OR: 6·6; 95% CI: 3·3-13·1). Among patients positive for influenza A(H1N1)pdm09 virus infection (n = 148), being pregnant (OR: 7·1; 95% CI: 1·6-31·2), clinically obese (OR: 2·9;95% CI: 1·6-31·2), and having an immunocompromising condition (OR: 3·7;95% CI: 1·1-13·4) were significantly associated with fatal outcomes.
  
  
  CONCLUSIONS
  These findings are consistent with several other investigations of risk factors associated with influenza A(H1N1)pdm09 virus infections. They also support the more recent 2012 recommendations by the WHO Strategic Advisory Group of Experts on Immunization (SAGE) that pregnant women are an important risk group for influenza vaccination. Ongoing sentinel surveillance can be useful tool to monitor risk factors for complications of influenza virus infections during each influenza season, and pandemics as well.
authors.affiliation: Ministry of Health, Bucharest, Romania.
authors.forename: Laurentiu
authors.initials: L
authors.lastname: Zolotusca
authors.forename: Pernille
authors.initials: P
authors.lastname: Jorgensen
authors.forename: Odette
authors.initials: O
authors.lastname: Popovici
authors.forename: Adriana
authors.initials: A
authors.lastname: Pistol
authors.forename: Florin
authors.initials: F
authors.lastname: Popovici
authors.forename: Marc-Alain
authors.initials: MA
authors.lastname: Widdowson
authors.forename: Viorel
authors.initials: V
authors.lastname: Alexandrescu
authors.forename: Alina
authors.initials: A
authors.lastname: Ivanciuc
authors.forename: Po-Yung
authors.initials: PY
authors.lastname: Cheng
authors.forename: Diane
authors.initials: D
authors.lastname: Gross
authors.forename: Caroline S
authors.initials: CS
authors.lastname: Brown
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Mott
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification*; D007251:Influenza, Human / Q000150:complications / Q000453:epidemiology* / Q000401:mortality* / Q000821:virology; D008297:Male; D008875:Middle Aged; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology / Q000401:mortality / Q000821:virology; D012189:Retrospective Studies; D012307:Risk Factors; D012383:Romania / Q000453:epidemiology; D016019:Survival Analysis; D055815:Young Adult
keywords: Influenza; Romania; risk factors; severe acute respiratory illness; surveillance