A major children's hospital in Tennessee is the latest to announce a requirement that all employees be vaccinated against COVID-19, which comes at a time when workplace mandates have sparked showdowns and lawsuits.
In a memo to staff sent Wednesday afternoon, employees of the St. Jude Children's Research Hospital, and its fundraising offshoot ALSAC, were informed of the requirement and given a Sept. 9 deadline to get vaccinated.
"By September 10, employees who have refused vaccination or do not have an approved medical or religious exemption will be put on an unpaid administrative leave for two weeks," wrote Dr. James R. Downing, president and CEO of the Memphis hospital.
"During this time, they have the opportunity to begin the vaccination process," he added. "Those who fail to start the vaccination process will be terminated at the end of the two-week period."
MORE: How COVID-19 vaccine policies have triggered lawsuits and workplace showdownsDowning noted the rapid spread of the delta variant, which he said is now responsible for some two-thirds of all COVID-19 cases in Memphis and Shelby County. He also expressed concern over the recent uptick in cases in the area and the potential of a corresponding surge in hospitalizations.
"Hundreds of millions of people around the world have safely received the COVID-19 vaccine," Downing wrote. "The benefits far outweigh the risks."
In statement to ABC News, St. Jude Children's Research Hospital said the decision to mandate vaccines was reached "after much research, analysis and discussion."
"It is the right thing to keep our campus safe," the hospital added. "Our duty to our patients frames everything we do. This is the logical next step to ensure we stay one step ahead of the virus."
The statement added that ALSAC and the hospital share a campus and thereby are jointly implementing the policy.
St. Jude has more than 3,600 employees, according to its website. The Memphis Business Journal reported that ALSAC had some 1,240 local employees.
The hospital is the latest in a slew of employers -- from school districts to airliners -- that have announced COVID-19 vaccine mandates as workplaces begin to reopen.
MORE: What to know if your employer requires vaccinations: federal legal protectionsThe Equal Opportunity Employment Commission said employers can legally require COVID-19 vaccinations to re-enter a physical workplace, as long as they follow requirements to find alternative arrangements for employees unable to get vaccinated for medical reasons or because they have religious objections.
MORE: Employers announce COVID-19 vaccine requirements as workplaces reopenStill, many employers have faced legal challenges and pushback from workers who refuse the shot.
More than 175 staffers at the Houston Methodist hospital were temporarily suspended without pay last month after not complying with a mandate, and a lawsuit was filed against the hospital. A Texas judge sided with the hospital, tossing out a lawsuit filed by 117 employees who were against getting the shot. Lawsuits over workplace vaccine requirements also have been leveled against a school district in California and a sheriff’s office in North Carolina.
Some 53% of the people 18 and older have received at least one dose of the vaccine in Tennessee, and 47.2% are fully vaccinated, according to data released Friday.
Nationally, the U.S. Centers for Disease Control and Prevention reports that 67.8% of the population over 18 has received at least one dose, and 59.1% are fully vaccinated. The public health agency has stated COVID-19 vaccines are "safe and effective," as lawmakers and more implore more Americans to get vaccinated.
"Millions of people in the United States have received COVID-19 vaccines since they were authorized for emergency use by FDA," the CDC said. "These vaccines have undergone and will continue to undergo the most intensive safety monitoring in U.S. history."
ABC News' Will Gretsky and Marlene Lenthang contributed to this report.