OSF HealthCare now says it will require all employees to be vaccinated against COVID-19 by the end of September.
Previously, the health care organization recommended vaccines, but left the final decision up to individuals.
OSF chief operating officer Mike Cruz said the health care group is "ethically obligated" to be vigilant about patient safety.
"Vaccinations are credited with the decline in COVID-19 hospitalizations and cases across the country and throughout our Ministry, and we firmly believe that vaccination against COVID-19 is the best way to keep our patients and Mission Partners safe," Cruz said in a prepared statement.
The health care organization already required annual flu shots, and other vaccinations like MMR and whooping cough. Employees who don't qualify for an exemption for religious or medical reason and still choose not to get vaccinated against COVID-19 could be subject to disciplinary measures, including firing.
OSF HealthCare employs nearly 24,000 people in Illinois and Michigan. An OSF spokesperson said about 65% of their employees are currently vaccinated, with the caveat that number is fluid moving forward.
A UnityPoint Health spokesperson said at this time, that health care group strongly encourages, but does not require, employees get vaccinated against COVID-19.