title: Effect of antiviral prophylaxis on influenza outbreaks in aged care facilities in three local health districts in New South Wales, Australia, 2014.
abstract: BACKGROUND
  There was a record number (n= 111) of influenza outbreaks in aged care facilities in New South Wales, Australia during 2014. To determine the impact of antiviral prophylaxis recommendations in practice, influenza outbreak data were compared for facilities in which antiviral prophylaxis and treatment were recommended and for those in which antivirals were recommended for treatment only.
  
  
  METHODS
  Routinely collected outbreak data were extracted from the Notifiable Conditions Information Management System for two Local Health Districts where antiviral prophylaxis was routinely recommended and one Local Health District where antivirals were recommended for treatment but not routinely for prophylaxis. Data collected on residents included counts of influenza-like illness, confirmed influenza, hospitalizations and related deaths. Dates of onset, notification, influenza confirmation and antiviral recommendations were also collected for analysis. The Mann-Whitney U test was used to assess the significance of differences between group medians for key parameters.
  
  
  RESULTS
  A total of 41 outbreaks (12 in the prophylaxis group and 29 in the treatment-only group) were included in the analysis. There was no significant difference in overall outbreak duration; outbreak duration after notification; or attack, hospitalization or case fatality rates between the two groups. The prophylaxis group had significantly higher cases with influenza-like illness (P= 0.03) and cases recommended antiviral treatment per facility (P= 0.01).
  
  
  CONCLUSIONS
  This study found no significant difference in key outbreak parameters between the two groups. However, further high quality evidence is needed to guide the use of antivirals in responding to influenza outbreaks in aged care facilities.
authors.affiliation: Hunter New England Local Health District, New South Wales, Australia .
authors.forename: Tony
authors.initials: T
authors.lastname: Merritt
authors.affiliation: Health Protection New South Wales, North Sydney, New South Wales, Australia .
authors.forename: Kirsty
authors.initials: K
authors.lastname: Hope
authors.affiliation: Hunter New England Local Health District, New South Wales, Australia .
authors.forename: Michelle
authors.initials: M
authors.lastname: Butler
authors.affiliation: Hunter New England Local Health District, New South Wales, Australia .
authors.forename: David
authors.initials: D
authors.lastname: Durrheim
authors.affiliation: Sydney Local Health District, Camperdown, New South Wales, Australia .
authors.forename: Leena
authors.initials: L
authors.lastname: Gupta
authors.affiliation: Sydney Local Health District, Camperdown, New South Wales, Australia .
authors.forename: Zeina
authors.initials: Z
authors.lastname: Najjar
authors.affiliation: South Western Sydney Local Health District, Liverpool, New South Wales, Australia .
authors.forename: Stephen
authors.initials: S
authors.lastname: Conaty
authors.affiliation: South Western Sydney Local Health District, Liverpool, New South Wales, Australia .
authors.forename: Leng
authors.initials: L
authors.lastname: Boonwatt
authors.affiliation: South Western Sydney Local Health District, Liverpool, New South Wales, Australia .
authors.forename: Stephanie
authors.initials: S
authors.lastname: Fletcher
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000998:Antiviral Agents / Q000627:therapeutic use*; D003428:Cross Infection / Q000517:prevention & control*; D004196:Disease Outbreaks / Q000517:prevention & control*; D005260:Female; D006707:Homes for the Aged / Q000706:statistics & numerical data*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007251:Influenza, Human / Q000453:epidemiology / Q000517:prevention & control*; D008297:Male; D009517:New South Wales / Q000453:epidemiology; D009735:Nursing Homes / Q000706:statistics & numerical data*; D065129:Pre-Exposure Prophylaxis
chemical_list: D000998:Antiviral Agents