Effect of influenza vaccination of nursing home staff on mortality of residents: a cluster-randomized trial

J Am Geriatr Soc. 2009 Sep;57(9):1580-6. doi: 10.1111/j.1532-5415.2009.02402.x. Epub 2009 Aug 4.


Objectives: To evaluate the effect of staff influenza vaccination on all-cause mortality in nursing home residents.

Design: Pair-matched cluster-randomized trial.

Setting: Forty nursing homes matched for size, staff vaccination coverage during the previous season, and resident disability index.

Participants: All persons aged 60 and older residing in the nursing homes.

Intervention: Influenza vaccine was administered to volunteer staff after a face-to-face interview. No intervention took place in control nursing homes.

Measurements: The primary endpoint was total mortality rate in residents from 2 weeks before to 2 weeks after the influenza epidemic in the community. Secondary endpoints were rates of hospitalization and influenza-like illness (ILI) in residents and sick leave from work in staff.

Results: Staff influenza vaccination rates were 69.9% in the vaccination arm versus 31.8% in the control arm. Primary unadjusted analysis did not show significantly lower mortality in residents in the vaccination arm (odds ratio=0.86, P=.08), although multivariate-adjusted analysis showed 20% lower mortality (P=.02), and a strong correlation was observed between staff vaccination coverage and all-cause mortality in residents (correlation coefficient=-0.42, P=.007). In the vaccination arm, significantly lower resident hospitalization rates were not observed, but ILI in residents was 31% lower (P=.007), and sick leave from work in staff was 42% lower (P=.03).

Conclusion: These results support influenza vaccination of staff caring for institutionalized elderly people.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Cause of Death
  • Disability Evaluation
  • Disease Outbreaks / prevention & control*
  • Disease Outbreaks / statistics & numerical data
  • Female
  • France
  • Homes for the Aged / statistics & numerical data*
  • Humans
  • Immunization Programs
  • Infectious Disease Transmission, Professional-to-Patient / prevention & control*
  • Infectious Disease Transmission, Professional-to-Patient / statistics & numerical data
  • Influenza Vaccines / administration & dosage*
  • Influenza, Human / mortality
  • Influenza, Human / nursing*
  • Influenza, Human / prevention & control*
  • Influenza, Human / transmission
  • Male
  • Matched-Pair Analysis
  • Nursing Homes / statistics & numerical data*
  • Nursing Staff / statistics & numerical data*
  • Sick Leave
  • Survival Analysis


  • Influenza Vaccines