Mandatory influenza vaccination of health care workers: a first-year success implementation by a community health care system.

Poudre Valley Health System is a private, not-for-profit health care system of more than 5,300 employees. Poudre Valley Health System increased its influenza vaccination coverage rate among health care workers from 68% in 2009 to 95.5% in 2010 after implementing a mandatory influenza vaccination program.