The vast majority of hospitals in the District and Maryland will soon start requiring employees to be vaccinated against the coronavirus, officials announced Wednesday, wading into politically fraught territory that in other parts of the country has led to protests and at least one lawsuit.

Leaders of hospitals and hospital associations said the decision was made to protect patients and staff members, citing the efficacy of the vaccine and noting its minimal side effects. Individual hospitals will establish their own timelines by which employees must be vaccinated, and some say they have no immediate plans to terminate employees who do not comply — instead, they will be required to undergo regular coronavirus testing.

Jacqueline D. Bowens, the president of the D.C. Hospital Association, said the decision to require vaccinations was not made lightly, especially because the pandemic has already led to concerns about staffing in the industry. But she said hospital leaders felt it was the right time to make such a move “due to both the science and the safety of the vaccine.”

“We believed this was the right thing to do,” Bowens said. “What we’re trying to do is what we believe is in the best overall interests of our workforce and the communities we serve.”

About 70 percent of hospital employees in D.C. and Maryland are fully vaccinated, the associations said. Employees who cite medical or religious reasons may receive exemptions from the requirement. The Equal Employment Opportunity Commission has said that employers can require vaccines, and President Biden is urging more Americans to get the shots to stave off new outbreaks and stem the spread of highly contagious variants.

But at one of the first hospitals to require vaccinations, there have been protests and nearly 200 employee suspensions this week. Workers at Houston Methodist Hospital in Texas also filed a lawsuit alleging that the hospital’s policy infringes on their rights.

Nancy Foster, vice president for quality and patient safety policy at the American Hospital Association, said she thinks D.C. and Maryland will probably be “at the beginning of a wave” of hospitals mandating vaccinations for their employees. She said the national group has not yet taken an official position but believes hospitals should “do everything they possibly can in order to protect our patients.”

Virginia Hospital and Healthcare Association spokesman Julian Walker said the group’s board of directors will consider whether to mandate vaccinations at member hospitals at its mid-July meeting.

“We’ve been evaluating these issues continually through the process,” Walker said, adding that the association “strongly encouraged” hospital staff members to get vaccinated last fall.

Bowens said the intent of the announcement from the D.C. Hospital Association is not to be punitive, noting that there will be a focus on employee education and that each hospital will be able to move on its own timeline, with some mandating vaccinations earlier than others.

D.C.’s private hospitals — including George Washington University Hospital, Children’s National Hospital, Howard University Hospital, MedStar Washington Hospital Center and Sibley Memorial Hospital — have all agreed to require vaccinations.

A spokeswoman for the Washington DC VA Medical Center, which is federally run, said the hospital is currently working on a count of how many of its employees are vaccinated and does not plan to require the shot in the near future. United Medical Center and St. Elizabeths Hospital, which are run by the D.C. government, will make their own decisions, Bowens said.

Toya Carmichael, a spokeswoman for United Medical Center, said the hospital is still weighing the issue. More than half of employees received their vaccinations at the hospital, she said, but there is no tally of how many got vaccinated in other settings.

Children’s Hospital will require all employees to be fully vaccinated by Sept. 30. Hospital president and chief executive Kurt Newman said that more than 75 percent of employees have already gotten their shots.

“We serve patients that range in age from newborns to young adults,” he said in a statement. “Currently, the vaccine is not authorized for children under the age of 12, so this new requirement for our employees is an important and meaningful way to safeguard the health of the children whose care is entrusted to us.”

In Maryland, officials said the adoption of a vaccine mandate was driven largely by the state’s two biggest hospital systems — Johns Hopkins Health System and the University of Maryland Medical System, which has about 29,000 employees across its 13 hospitals statewide. The U-Md. system will require all employees, contractors and volunteers to be vaccinated after at least one of the provisionally approved vaccines is granted full approval by the U.S. Food and Drug Administration.

Until that happens, there will be two options: Starting Sept. 1, employees can either get vaccinated, or, if they are unvaccinated, participate in weekly coronavirus testing. The deadline for managers is Aug. 1.

“This is actually keeping quite consistent with the expectations we have for each other as health-care workers,” said Mohan Suntha, the chief executive of the system. “So my hope and expectation is that our collective workforce will recognize this obligation that we have.”

At Johns Hopkins, new employees will be required to be vaccinated beginning July 1, said chief executive Kevin Sowers. Current employees who work in person have until Sept. 1 to get vaccinated or commit to weekly testing and wearing personal protective gear; managers have until Aug. 1. Medical exemptions for now include women who are pregnant or trying to become pregnant, he said.

Sowers said he anticipates that all employees will be mandated to get vaccinated in a future phase, although there is not yet a timeline for when that would happen. About 79 percent of employees across the Hopkins system have been vaccinated, he said.

Those who express hesitancy about the vaccines have similar concerns as members of the general public, Sowers said, noting that Johns Hopkins will keep reaching out to those who remain wary.

“We didn’t want to jump to termination right away,” he said. “We want to try to work with our workforce to help them come along.”

Jenna Portnoy and Julie Zauzmer contributed to this report.