Employees covered by union contracts would in all likelihood be exempt, legal experts say. Employees also can claim exemptions on religious grounds or because of existing medical disabilities.
Employers are required by federal law to make "reasonable accommodations" for those who refuse to get vaccinated — a step that could include physically isolating them from their co-workers, said Elizabeth Stallard, a labor-law specialist at the DowneyBrand law firm in Sacramento.
Above all, fighting human nature may be the biggest enemy. If the goal is to get as many people vaccinated as possible, it could backfire as people push back against the government dictating what they put in their bodies.
That's particularly true, ironically, in the health care sector.
As a practical matter, hospitals don't want "to enforce a rule against the will of a significant number of people," said Lisa Ikemoto, a University of California, Davis law professor who specializes in health care law. "Making it voluntary may be the most effective way to get compliance."
Even state Sen. Richard Pan, D-Sacramento, a physician who has spearheaded legislation to close loopholes that allow parents to keep their school-age kids from getting vaccinated against childhood diseases, said he's leery about any mass COVID-19 vaccine mandates for adults.
Instead, he expects more people will get over their hesitancy as they see their friends, family members and neighbors get the shots and have no ill health effects.
Plus, he said, many businesses — airlines, cruise ships and the like — are going to eventually require proof of vaccination for customers. Pan said when people "really want something," such as going on a vacation, they'll get vaccinated.
" 'No mask; no service;' 'No vaccine; no service,' " he said. "That's up to the business."
For the moment, though, vaccine hesitancy is widespread, and threatening to push recovery from the pandemic further out of reach.