Requiring employees to receive flu shots is not a primary reason for quitting, a four-year analysis finds.

While the Centers for Disease Control and Prevention recommends healthcare employees receive the annual flu vaccine, facilities vary on whether to it make it mandatory.

In 2009, Loyola University Medical Center made flu shots a requirement as an employment condition for employees, students, volunteers and contractors. In the first year, 99.2% of employees received the vaccine, with .7% being exempt for religious or medical reasons, and 0.1% choosing to leave rather than get the shot. By 2012, while the rate of exemption rose to 1.2%, only 0.6% refused vaccination and chose to leave. However, of the five people who refused to be vaccinated, three were unpaid volunteers and two were part-time staff, explained Jorge Parada, M.D, MPH, the study’s author and professor of medicine at Loyola University Chicago Stritch School of Medicine.

Over four years, fewer than 15 people out of 8,000 chose termination over vaccination, he said.

Results were presented during the Association for Professionals in Infection Control and Epidemiology Conference this week in Florida.