DENVER - Colorado hospital employees are being threatened with their jobs if they don't get a flu shot by the end of the year.

New state health regulations require flu shots for health care workers to be phased in over the next several years. Right now the rules only apply to about two-thirds of those workers.

Colorado Health and Hospital Association president Steven Summer says workers need to be healthy if Colorado gets hit with a flu outbreak.

The Colorado Department of Public Health and Environment tells KCNC-TV it's up to hospitals if they want to go beyond the current requirements.

The only way hospital workers can avoid a flu shot is for medical reasons. In those cases, health care workers are required to wear masks.