The delta variant is driving a record number of COVID-19 patients to Mayo Clinic's hospital in Florida, adding urgency to the clinic's new call for more workers to get vaccinated.

The majority of those employed by Mayo already have been immunized, but the clinic announced last week that workers throughout the Rochester-based health system must either get vaccinated or go through an hourlong education session by next month.

"We wanted to push this even further," said Dr. Amy Williams, executive dean of the Mayo Clinic Practice. "The reason that we said, 'We have to do this now,' is because of what we were seeing with the increased number of COVID-19 cases nationally."

Mayo's push falls short of a vaccine mandate, but it's a variation on a quickly emerging trend among employers that, while becoming a flash point, is fueled by new worries over the pandemic's unpredictably serious turns.

Some workplace policies are making it more of a hassle for workers to resist the vaccine. Others culminate in unvaccinated employees losing their jobs.

The changes are most prominent in health care, where the number of hospital systems announcing vaccine mandates and other measures jumped from fewer than 100 three or four weeks ago to 800 or more by the end of July, said Akin Demehin, director of policy at the American Hospital Association. There are signs of growing interest in other sectors as well.

Google and Facebook said last week that as the tech companies reopen campuses, anyone coming to work must be fully vaccinated. In California and New York City, unvaccinated government workers soon will be subject to routine COVID-19 testing. President Joe Biden announced Thursday that federal employees who aren't immunized must undergo testing, wear masks and keep physically distant.

"It seems like there's really been a shift," said Susan Ellingstad, a partner at Lockridge Grindal Nauen who specializes in workplace legal issues. "I think that [employers] can make a big difference from a public health perspective because we've kind of run out of other ways to get people vaccinated."

In general, employers have been reluctant to mandate the vaccine because they want to be respectful of employees and honor their personal health decisions, said Doug Loon, president of the Minnesota Chamber of Commerce.

An online survey of 130 companies by the chamber in late June found that only about 5% of respondents were requiring vaccine. A new survey is underway. Mandates clearly are growing among health care organizations, Loon said, but the best practice for most employers has been to simply encourage vaccination.

"Will employers go from this incentive strategy to a mandate strategy? I think time will tell," Loon said.

Unions traditionally have opposed vaccine mandates, and some are stressing that COVID-19 vaccination should remain voluntary. Lawmakers are watching.

"I do have concerns if they're treating this vaccination against this disease differently than they've treated other vaccinations," Sen. Michelle Benson, R-Ham Lake, said.

For months, South Dakota-based Sanford Health has promoted vaccination for workers, but it announced in July a vaccine mandate that's much like what's required for influenza.

With hospitals and clinics across the Dakotas and western Minnesota, Sanford is calling on its 46,000 workers to get vaccinated or qualify for a medical or religious exemption to the employer's vaccine mandate by Nov. 1. Those who fail to do so will be furloughed for 60 days and could then be viewed as voluntarily resigning if they're still not immunized.

The policy is similar to one adopted earlier this year by Houston Methodist, a large health system in Texas where 153 workers who did not comply either resigned or were terminated out of an overall employee base of 26,000. Sanford Health hopes it won't lose any workers, but the experience in Houston and elsewhere suggests the health system might lose 1% or less of its workforce, Sanford Health Chief Executive Bill Gassen said.

"We need to make sure that we're doing everything we can to protect our patients and our residents and our employees and the communities that we serve," Gassen said. "As a result, this becomes a very easy decision to make."

The spread of the delta variant underscored the need for the change, said Randy Bury, president and chief executive for Good Samaritan Society, the health system's long-term care division. Three long-term care facilities in the past few weeks, he said, saw COVID-19 cases in unvaccinated workers who then apparently passed the virus to fully vaccinated residents.

Long-term care facilities have been reluctant to mandate COVID-19 vaccine for fear it will exacerbate a worker shortage. With 142 skilled nursing facilities across 26 states, including Minnesota, Good Samaritan Society understands the tension, Bury said, but also recognizes that a resurgent COVID-19 could create staffing problems with outbreaks among workers.

"The quickest way to get out of this pandemic is to mandate the vaccine and stop this thing in its tracks so this variant doesn't keep spreading," he said. "We're not going to sit idly by, with this ability to stop this thing, and just watch it spread from building to building like we were forced to do when the virus first started."

In early July, the Federal Reserve Bank of Minneapolis announced it was making full vaccination against COVID-19 a condition of employment. All employees must be vaccinated with the exception of those receiving a medical or religious exemption, the Minneapolis Fed said, and workers have until Aug. 13 to come into initial compliance.

The new policy at Mayo, however, is more limited, because it calls for workers to get vaccinated or go through a "declination process" by Sept. 17.

"It falls short of: 'If you don't do this, you will be fired,' " Williams said. "If they decline, they need to go through very robust education."

Mayo is developing the "educational module" on the vaccine. Workers will be asked to indicate on a form why they're declining vaccine. Options likely will go beyond the exemptions for medical or religious reasons found in stricter policies, Williams said.

Starting Sept. 1, COVID-19 vaccination will be a condition of employment for all new hires at Mayo.

"We were feeling really good a month ago," Williams said. "And then we started to see this delta variant spread and get very close to home. And we realized that we needed to change."

Christopher Snowbeck • 612-673-4744

Twitter: @chrissnowbeck