title: Unusually high impact of influenza B during the early 2012-2013 influenza season in Wales--epidemiology and clinical analysis of the first 100 cases.
abstract: BACKGROUND
  Influenza B is often regarded as the milder form of the disease. The early 2012-2013 season in Wales saw the highest rate of influenza B-associated primary care consultations since 1994-1995 and considerable hospitalisations.
  
  
  OBJECTIVE
  This report summarises features of the first 100 confirmed cases during 2012-2013 in Wales.
  
  
  METHODS
  Case information was sourced from routine laboratory testing and virological surveillance.
  
  
  CONCLUSIONS
  Influenza B (Yamagata lineage) viruses dominated, mainly affecting younger adults, admission to critical care was unexpectedly common. Low vaccine uptake amongst at-risk patients may have contributed to the burden of influenza in secondary care in Wales.
authors.affiliation: Public Health Wales Communicable Disease Surveillance Centre, Health Protection Division, Public Health Wales NHS Trust, Temple of Peace and Health, Cardiff, UK.
authors.forename: Simon L
authors.initials: SL
authors.lastname: Cottrell
authors.forename: Catherine
authors.initials: C
authors.lastname: Moore
authors.forename: Laura
authors.initials: L
authors.lastname: Dexter
authors.forename: Daniel Rh
authors.initials: DR
authors.lastname: Thomas
authors.forename: Roland L
authors.initials: RL
authors.lastname: Salmon
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D009981:Influenza B virus / Q000302:isolation & purification*; D007251:Influenza, Human / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D008297:Male; D008875:Middle Aged; D011320:Primary Health Care / Q000706:statistics & numerical data; D014611:Vaccination / Q000706:statistics & numerical data; D014852:Wales / Q000453:epidemiology
keywords: Influenza; Wales; influenza B; severity; surveillance
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