CHICAGO (CBS) — In Chicago all city workers are now being told they must get the COVID-19 vaccine by Oct. 15, but it’s unclear what happens to those who don’t do it.

Mayor Lori Lightfoot made the mandate very clear in a tweet saying, “We must take every step necessary and at our disposal to keep everyone in our city safe and healthy. That’s why all City of Chicago employees are required to be fully vaccinated, effective October 15. Get your vax, folks.”

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The mandate applies to more than 30,000 city workers, including police officers. Their union opposes the mandate.

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“The pathway has been cleared for companies to legally mandate it, is a really big issue,” said Andy Challenger with Challenger, Gray and Christmas, a career coaching firm. He said the mandate is starting to look like the norm.

“In the last two or three weeks a number of large Fortune 500 companies announced that they’re going to mandate the vaccine for their employees or ask them to take a COVID test each week before they come into the office,” he said.

“In the last two or three weeks, a number of large Fortune 100 companies announced that they’re going to mandate the vaccine for their employees or ask them to take a covid test each week before they come into the office.”

About 15,000 union city employees fall under the Chicago Federation of Labor umbrella. Among those the union represents are teachers, laborers and firefighters. The union issued a statement that says in part:

“We believe in the benefits of vaccination to help protect workers and residents, but we do not believe punitive mandates are the right path to significantly increase vaccine uptake. In fact, we believe this announcement may harden opposition to the vaccine…”

Challenger said many companies are taking different approaches for those who don’t comply with the COVID-19 vaccine mandate.

“‘You either show us your vaccine cards or you’re going to have to be regularly tested,'” he said.

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The mayor’s announcement does not say what will happen to city workers who refuse to get vaccinated. When CBS 2 asked the mayor’s office about this, we were told Wednesday’s announcement is preliminary information, and there will be more to come.

Suzanne Le Mignot