“We were all traumatized, vaccinated and unvaccinated,” said Ms. Conrad, who works at United Memorial, a hospital in Batavia, a small city midway between Rochester and Buffalo, and felt respected by colleagues there. “It’s very hard that the same people who elevated me to this level now look at me as a dangerous person.”

The dispute is dividing hospitals, where most workers are vaccinated and want their colleagues to be. The nurses’ union supports the mandate — some 95 percent of members are already vaccinated — even as some members complain its rollout was too rushed. But unions representing support workers, including nurses’ aides, orderlies, cafeteria workers and others, have opposed it. If many of those workers leave or are fired, their duties could fall to already taxed nurses…

Still, staff members choosing to exit their jobs because of the mandate could also create immediate practical challenges: Many nurses and other health workers are burned out or traumatized from the pandemic’s strain; others have been lured by high salaries to become “travel nurses,” crisscrossing the country to fill emergency staffing gaps.