title: Detection and control of influenza outbreaks in well-vaccinated nursing home populations.
abstract: BACKGROUND
  Influenza outbreaks continue to occur in nursing homes despite high vaccination coverage among residents. Recommendations for outbreak control in institutions such as nursing homes advises use of antiviral drugs to reduce influenza transmission.
  
  
  METHODS
  Influenza surveillance was performed among elderly residents of nursing homes in Michigan during 2 influenza seasons. The antiviral drug oseltamivir was used for outbreak control at the discretion of nursing home staff once influenza transmission was confirmed by virus isolation or rapid antigen detection.
  
  
  RESULTS
  During 2000-2001, influenza was not confirmed in any of the 28 participating homes, despite transmission of types A (H1N1) and B in the community. During 2001-2002, influenza type A (H3N2) transmission was confirmed in 8 (26%) of 31 participating homes; influenza vaccine coverage among residents was 57%- 98% in outbreak-associated homes. Oseltamivir was used in all homes with influenza transmission; outbreak control varied according to the rapidity of outbreak recognition and the extent of antiviral use. Reported adverse events were primarily gastrointestinal reactions and rashes. Analysis of the usefulness of rapid antigen detection tests for outbreak recognition indicated a sensitivity of only 77% (specificity, 92%).
  
  
  CONCLUSIONS
  Oseltamivir was reasonably well tolerated, and its use, along with continued promotion of vaccination coverage among nursing home residents and staff, should be a valuable addition to institutional outbreak-control strategies.
authors.affiliation: Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI 48109-2029, USA. asmonto@umich.edu
authors.forename: Arnold S
authors.initials: AS
authors.lastname: Monto
authors.forename: Judy
authors.initials: J
authors.lastname: Rotthoff
authors.forename: Esther
authors.initials: E
authors.lastname: Teich
authors.forename: M Louise
authors.initials: ML
authors.lastname: Herlocher
authors.forename: Rachel
authors.initials: R
authors.lastname: Truscon
authors.forename: Hui-Ling
authors.initials: HL
authors.lastname: Yen
authors.forename: Stephanie
authors.initials: S
authors.lastname: Elias
authors.forename: Suzanne E
authors.initials: SE
authors.lastname: Ohmit
mesh_terms: D000081:Acetamides / Q000009:adverse effects / Q000627:therapeutic use; D000368:Aged; D000998:Antiviral Agents / Q000627:therapeutic use; D019937:Diagnostic Techniques and Procedures / Q000639:trends; D004196:Disease Outbreaks / Q000517:prevention & control*; D006707:Homes for the Aged / Q000639:trends*; D006801:Humans; D017589:Immunization Programs / Q000639:trends*; D009980:Influenza A virus / Q000187:drug effects / Q000276:immunology; D009981:Influenza B virus / Q000187:drug effects / Q000276:immunology; D007251:Influenza, Human / Q000188:drug therapy / Q000453:epidemiology* / Q000517:prevention & control*; D008824:Michigan / Q000453:epidemiology; D009735:Nursing Homes / Q000639:trends*; D019370:Observation / Q000379:methods; D053139:Oseltamivir; D011159:Population Surveillance / Q000379:methods*; D012621:Seasons; D012680:Sensitivity and Specificity
chemical_list: D000081:Acetamides; D000998:Antiviral Agents; D053139:Oseltamivir