(CBS DETROIT) – Spectrum Health will allow workers to avoid its vaccine mandate if they can prove they have a natural immunity to COVID-19.

This makes it the first major system in Michigan with this type of exemption.

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“While we still recommend vaccination for people with prior COVID-19 infection, according to this new research, there is increasing evidence that natural infection affords protection from COVID-19 reinfection and severe symptoms for a period of time,” Spectrum said in a statement, which was shared in an article by the Detroit News. “Current studies are not clear on how long natural immunity protects from reinfection.”

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Under the policy, workers will have to get an antibody test to prove their immunity.

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