title: Incidence of influenza-associated mortality and hospitalizations in Argentina during 2002-2009.
abstract: BACKGROUND
  We estimated rates of influenza-associated deaths and hospitalizations in Argentina, a country that recommends annual influenza vaccination for persons at high risk of complications from influenza illness.
  
  
  METHODS
  We identified hospitalized persons and deaths in persons diagnosed with pneumonia and influenza (P&I, ICD-10 codes J10-J18) and respiratory and circulatory illness (R&C, codes I00-I99 and J00-J99). We defined the influenza season as the months when the proportion of samples that tested positive for influenza exceeded the annual median. We used hospitalizations and deaths during the influenza off-season to estimate, using linear regression, the number of excess deaths that occurred during the influenza season. To explore whether excess mortality varied by sex and whether people were age <65 or ≥ 65 years, we used Poisson regression of the influenza-associated rates.
  
  
  RESULTS
  During 2002-2009, 2411 P&I and 8527 R&C mean excess deaths occurred annually from May to October. If all of these excess deaths were associated with influenza, the influenza-associated mortality rate was 6/100,000 person-years (95% CI 4-8/100,000 person-years for P&I and 21/100,000 person-years (95% CI 12-31/100,000 person-years) for R&C. During 2005-2008, we identified an average of 7868 P&I excess hospitalizations and 22,994 R&C hospitalizations per year, resulting in an influenza-associated hospitalization rate of 2/10,000 person-years (95% CI 1-3/10,000 person-years) for P&I and 6/10,000 person-years (95% CI 3-8/10,000 person-years) for R&C.
  
  
  CONCLUSIONS
  Our findings suggest that annual rates of influenza-associated hospitalizations and death in Argentina were substantial and similar to neighboring Brazil.
authors.affiliation: Influenza Division, U.S. Centers for Disease Control and Prevention, Atlanta, GA, USA. eha9@cdc.gov
authors.forename: Eduardo
authors.initials: E
authors.lastname: Azziz-Baumgartner
authors.forename: Ana María
authors.initials: AM
authors.lastname: Cabrera
authors.forename: Po-Yung
authors.initials: PY
authors.lastname: Cheng
authors.forename: Enio
authors.initials: E
authors.lastname: Garcia
authors.forename: Gabriela
authors.initials: G
authors.lastname: Kusznierz
authors.forename: Rogelio
authors.initials: R
authors.lastname: Calli
authors.forename: Clarisa
authors.initials: C
authors.lastname: Baez
authors.forename: María Pía
authors.initials: MP
authors.lastname: Buyayisqui
authors.forename: Eleonora
authors.initials: E
authors.lastname: Poyard
authors.forename: Emanuel
authors.initials: E
authors.lastname: Pérez
authors.forename: Ricardo
authors.initials: R
authors.lastname: Basurto-Davila
authors.forename: Rakhee
authors.initials: R
authors.lastname: Palekar
authors.forename: Otavio
authors.initials: O
authors.lastname: Oliva
authors.forename: Airlane Pereira
authors.initials: AP
authors.lastname: Alencar
authors.forename: Regilo
authors.initials: R
authors.lastname: de Souza
authors.forename: Thais
authors.initials: T
authors.lastname: dos Santos
authors.forename: David K
authors.initials: DK
authors.lastname: Shay
authors.forename: Marc-Alain
authors.initials: MA
authors.lastname: Widdowson
authors.forename: Joseph
authors.initials: J
authors.lastname: Breese
authors.forename: Horacio
authors.initials: H
authors.lastname: Echenique
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001118:Argentina / Q000453:epidemiology; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D007251:Influenza, Human / Q000453:epidemiology* / Q000401:mortality* / Q000628:therapy; D008297:Male