title: Influenza vaccine effectiveness in Australia: results from the Australian Sentinel Practices Research Network.
abstract: OBJECTIVE
  To estimate influenza vaccine coverage and effectiveness against medically attended laboratory-confirmed influenza for the 2012 season.
  
  
  METHODS
  Test-negative design involving patients recruited as part of the Australian Sentinel Practices Research Network, a network of sentinel general practitioners throughout Australia. Throughout 2012, at the discretion of the GP at one of 102 participating practices, patients presenting with influenza-like illness were swabbed and included in the study.
  
  
  METHODS
  Influenza vaccine effectiveness (VE) estimated as (1-OR)*100% by logistic regression.
  
  
  RESULTS
  1775 patients were swabbed. The epidemic period was identified as Weeks 10 to 43 of 2012. After exclusions, there were 1414 patients for the VE analysis, including 593 (42%) who tested influenza-positive and 821 who tested negative. 27% of test-negative patients were vaccinated, of whom most were aged 50 years and over. The overall VE, adjusted for age group, month of presentation and state or territory, was 23% (95% CI, -4% to 43%) against all influenza types, 15% (95% CI, -17% to 38%) against influenza A, 13% (95% CI, -20% to 36%) against influenza A(not H1) and 53% (95% CI, 5% to 77%) against influenza B.
  
  
  CONCLUSIONS
  Vaccination against influenza was modestly protective, reducing the risk of medical presentation with influenza by around 23%.
authors.affiliation: WHO Collaborating Centre for Reference and Research on Influenza, Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia. sheena.sullivan@influenzacentre.org.
authors.forename: Sheena G
authors.initials: SG
authors.lastname: Sullivan
authors.affiliation: Discipline of General Practice, University of Adelaide, Adelaide, SA, Australia.
authors.forename: Monique B-N
authors.initials: MB
authors.lastname: Chilver
authors.affiliation: Microbiology and Infectious Diseases, SA Pathology, Adelaide, SA, Australia.
authors.forename: Geoff
authors.initials: G
authors.lastname: Higgins
authors.affiliation: Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, VIC, Australia.
authors.forename: Allen C
authors.initials: AC
authors.lastname: Cheng
authors.affiliation: Discipline of General Practice, University of Adelaide, Adelaide, SA, Australia.
authors.forename: Nigel P
authors.initials: NP
authors.lastname: Stocks
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D058006:General Practice; D006801:Humans; D007223:Infant; D007252:Influenza Vaccines; D007251:Influenza, Human / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D018571:Sentinel Surveillance; D014611:Vaccination / Q000706:statistics & numerical data; D055815:Young Adult
chemical_list: D007252:Influenza Vaccines