A Minnesota-based health system has fired about 50 employees who refused to get a flu shot.

Essentia Health announced last month that employees would be required to get vaccinated for influenza unless they received a religious or medical exemption.

The company said it wanted to help keep patients from getting sick at its 15 hospitals and 75 clinics in Minnesota, Idaho, North Dakota and Wisconsin.

Essentia says 99 percent of the company’s 13,900 eligible employees had gotten the shot, received an exemption or were getting an exemption by the Monday deadline.