For dozens of employees at Essentia Health, Monday meant coming to work not knowing whether they would make it to Tuesday. All because of the flu shot.

“Purely voluntary or more education doesn’t get you those high levels of immunization compliance,” said Dr. Rajesh Prabhu, the company’s chief of patient quality and safety. Prabhu said it was essential that he take a mandatory approach.

Since September, Essentia has told employees, volunteers, students and vendors that they have three options: get the flu shot, get an approved religious or medical exemption, or leave Essentia.

So far, he said 99.5 percent of employees have chosen the first two options. But 50 or so have been terminated, with more left waiting to hear back on their exemptions.

Minnesota Nurses Association Duluth Chair Steve Strand said with so many employees in that limbo, his union doesn’t know how many members have lost their jobs just yet.