The objective of this study is to demonstrate that influenza vaccination of nursing home workers is an effective intervention for reducing mortality of elderly people.

Nursing homes will be randomized within each pair in two arms "incentive to vaccinate", and "do-nothing". In the arm "incentive to vaccinate", vaccination campaigns will be carried out with face-to-face interviews of nursing home workers in order to achieve more than 80% of vaccination coverage. In the "do-nothing", nursing home workers will be vaccinated as usual.

The main endpoint criterion is all-cause mortality of residents. Population sets will be all residents who will be present at start of the influenza season (-2 weeks) or who will be admitted during the influenza season (+ 2 weeks). Onset and end of influenza season will be given by regional influenza surveillance system. Secondary criteria are hospitalizations of residents, morbidity of nursing home workers. A cost-effectiveness ratio of influenza vaccination will be calculated.

Inclusion Criteria:

Criteria for nursing home:

• Nursing home whose representative physicians agree to participate, with 50 to 200 residents, located in Paris area, and where the vaccination coverage of nursing home workers was lower than 40% during the previous influenza season (2005).

Criteria for residents:

• All residents who will be present at start of the influenza season (-2 weeks) or who will be admitted during the influenza season (+ 2 weeks).

Exclusion Criteria:

• People before 60 years Not presences in the EHPAD at the time of the beginning of the study (at the moment of the beginning of the epidemic - 2 weeks) or not allowed before the end of the study (before the end of the epidemic + 4, weeks)