Randomized trial of a program to increase staff influenza vaccination in primary care clinics

Although vaccination of health care workers against influenza is widely recommended, vaccination uptake is low. Data on interventions to increase staff immunization in primary care are lacking. We examine the effect of a promotional and educational intervention program, not addressing vaccine availability, to raise the influenza vaccination rate among staff in primary care clinics.

The study included all 344 staff members with direct patient contact (physicians, nurses, pharmacists, and administrative and ancillary staff) in 27 primary care community clinics in the Jerusalem area during the 2007-2008 influenza season. Thirteen clinics were randomly selected for an intervention that consisted of a lecture session given by a family physician, e-mail-distributed literature and reminders, and a key figure from the local staff who personally approached each staff member.

Influenza immunization rate was 52.8% (86 of 163) in the intervention group compared with 26.5% (48 of 181) in the control group (P<.001). When compared with the rate of immunization for the previous season, the absolute increase in immunization rate was 25.8% in the intervention clinics and 6.6% in the control clinics. Multivariate analysis showed a highly significant (P<.001) independent association between intervention and immunization, with an odds ratio of 3.51 (95% confidence interval, 2.03-6.09).

We have developed an effective intervention program to increase previously low vaccination rates among primary health care workers. This simple intervention could be reproduced easily in other clinics and organizations with an expected substantial increase in influenza immunization rates.