The Equal Employment Opportunity Commission (EEOC) on Friday issued updated guidance saying companies can legally require their employees to get a Covid-19 vaccine—but some workers, including some at one hospital, are fighting back against vaccine mandates.

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EEOC issues new guidance

In the guidance, EEOC said companies can require employees to receive Covid-19 vaccines, although they must also provide reasonable accommodations to those exempt from mandatory vaccines under the Americans with Disabilities Act and Title VII of the Civil Rights Act.

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Further, if employers offer on-site vaccinations, they must keep all personal medial records obtained confidential, the guidance said.

EEOC also said employers can offer incentives for their employees to get vaccinated, but the incentives cannot be "coercive."

But according to Helen Rella, an employment attorney at Wilk Auslander, the precise meaning of that term remains unclear. "[O]ne person's view of what is a coercive incentive is not the same as another person's," Rella said. "You might find an incentive of $100 coercive, and another person might find an incentive of $10,000 coercive. That's where the door is left open, (where) we don't have the detailed guidance we were hoping to receive."

Some employees at Houston Methodist Hospital file suit over vaccine mandate

The updated guidance comes as a group of 117 employees at Houston Methodist Hospital filed a lawsuit over the hospital's vaccine requirement for employees.

The hospital has given employees a deadline of June 7 to receive a Covid-19 vaccine. If they don't, they risk suspension and eventually termination. The hospital offers "religious and medical exemptions, as well as deferrals for pregnant women," it told ABC News.

According to Jared Woodfill, an attorney representing the plaintiffs, some of the plaintiffs are nurses, but the majority are not health care workers.

Akiko Iwasaki, an immunologist at Yale University, argued the lawsuit makes unfounded claims about the safety of mRNA-based vaccines. "There were tens of thousands of people who were in the Phase 3 clinical trials for the mRNA vaccines, and no safety concerns were found," Iwasaki said.

Marc Boom, CEO of Houston Methodist, said 99% of the hospital's 26,000 employees have received a Covid-19 vaccine, and he contended that receiving a vaccine is part of the "sacred obligation" of health care providers.

"It is unfortunate that the few remaining employees who refuse to get vaccinated and put our patients first are responding in this way," Boom said. "It is legal for health care institutions to mandate vaccines, as we have done with the flu vaccine since 2009. The Covid-19 vaccines have proven through rigorous trials to be very safe and very effective and are not experimental" (Herman, Axios, 5/28; Cerullo, CBS News, 5/30; Downen, Houston Chronicle, 5/28; Lenthang, ABC News, 5/29; Hawkins, Washington Post, 5/29).