Vaccination status itself isn’t a protected category (such as race, sex, or age) under equal employment opportunity laws, but the EEOC’s guidance makes clear that employers must provide certain accommodations for employees who aren’t vaccinated against COVID-19 on the basis of a disability, a sincerely held religious belief or practice, or pregnancy – which means employers can’t discriminate or retaliate against employees who don’t receive vaccinations for those reasons.
The federal prohibitions on discrimination cover employment practices like hiring and termination, job transfers and promotions, pay, fringe benefits (such as health care), and “other terms and conditions of employment.” Federal law also forbids retaliation against an employee for complaining about discrimination and harassment based on a protected category. In addition, the EEOC guidance repeatedly recommends that employers train supervisors, managers, and HR staff to avoid illegal discrimination against employees in the context of the pandemic generally and vaccinations specifically.
At the same time, however, federal employment law doesn’t prevent institutions from enacting certain policies that treat employees differently based on their vaccination status.  For example, based on guidance from OSHA, employers can – and in fact, should – require unvaccinated employees to wear masks, maintain social distancing, or take other safety measures that might not apply to vaccinated employees for the purpose of preventing the spread of COVID-19 in the workplace.
Finally, institutions must consider applicable state laws. Multiple states have considered specifically prohibiting employment discrimination based on vaccination status, and at least one state, Montana, enacted such a law in May 2021. Consult legal counsel about your state’s requirements.