“Thank God,” S. Jeanie Clark thought to herself this week, as a nurse and sheriff’s deputy showed up at her door.

Clark, 77, sat on the edge of a hospital bed wedged into the living room of her Front Royal, Va., home that she hasn’t left since she was diagnosed with double pneumonia a year ago.

She was one of 17 people whom the nurse and deputy visited on Wednesday as they brought coronavirus vaccine to homebound seniors, one by one.

In Virginia and around the country, supplies of vaccine have begun outstripping demand for shots, forcing public health officials to shift their focus from large-scale clinics to creative and targeted strategies for delivering vaccine to hard-to-reach populations.

That means driving doses around rural counties and small towns, deploying mobile units the size of ice cream trucks with as few as 50 shots to neighborhoods, and making sure family physicians have shots to inoculate patients who might not trust anyone else.

Sheriff’s departments are playing a key role in the Shenandoah Valley, where deputies already know who is medically vulnerable and how to find their way around sprawling counties and back roads.

On Wednesday morning, Cindy Burke, a Warren County sheriff’s deputy, donned her uniform — complete with bulletproof vest and firearm — and drove public health nurse Paula Mills from house to house in her department vehicle. Clark’s home was their second stop of seven over about five hours.

Just inside Clark’s front door, Burke kept silent watch as Mills, in navy blue scrubs, answered Clark’s worried questions about potential side effects of the vaccine.

“Am I scared? Yes,” Clark said, as her fluffy white dog, Shakes­peare — Shaky for short — peeked out from behind the bed. “Does it affect your lungs in any way?”

“No,” Mills said. “The data out there does not say that it does — and we definitely know that the covid illness does, and it can.”

Clark, who uses portable oxygen, said she worried she could be exposed to the coronavirus through the caregivers who visit her at her home. She and her adult daughter both tried for months to arrange a home vaccination through the local and state health departments, pharmacies, Walmart, even the Centers for Disease Control and Prevention — to no avail.

She said she was “flabbergasted” when the Warren County Sheriff’s Department called, offering a dose.

After she was vaccinated, Clark turned gratefully to Burke.

“You guys have been there for us all the time,” she said to the deputy. “I mean within the neighborhood, we have a problem, we call you, you’re there, so we appreciate you. Believe me, you’re number one on our list.”

“Well, you’re number one on ours,” Burke said.

But the approach will not work everywhere. Some of the people public health workers are trying to reach with vaccine may be intimidated by a law enforcement officer knocking on their door, or reluctant to answer.

Mindful of the challenge, public health officials in the region have worked with Black clergy and the NAACP, poultry plant and farmworkers and liaisons at an elementary school with many Hispanic families to hold clinics catered to each community.

Warren County Sheriff Mark Butler, who was a longtime police officer in Fairfax and Herndon before taking office in 2020, said deputies enforce the laws in the 200-square-mile region — but also are used to providing social services, such as delivering Meals on Wheels, tracking residents with medical conditions who wear a small transmitter in case they go missing or need help, and calling frail and homebound people daily to check on them. The vaccination program fits in with that mission, he said.

As of Friday, 31 percent of the population of Warren County had received at least one dose — less than the state average of 44 percent, state data shows.

Nearly half of the state’s 3,391 homebound Medicaid recipients received at least one dose as of Tuesday, said Christina Nuckols, spokeswoman for the Virginia Department of Medical Assistance Services. These individuals cannot leave their homes to be vaccinated and often require in-home nursing care.

“It’s been really slow going in recent weeks because people don’t want it, they don’t want to be vaccinated,” Danny Avula, the state’s vaccine coordinator, said in a phone interview Thursday, referring to the homebound.

Colin Greene, a physician and the health director in charge of a region with 10 counties, including Warren County and the city of Winchester, rejected attempts to generalize about those who are hesitant.

“You really can’t stereotype people on this one; you have to listen to their concerns,” he said. “There are a large group of people out there who just have a fear of something new.”

In addition to reaching out to people who want the shot and haven’t been able to access it, Greene wrote two op-eds for local papers in hopes of persuading the hesitant.

“Every person vaccinated is one less likely to suffer or die from covid-19, and one more person that can safely hug their family and friends, and enjoy the human company so badly missing in northwestern Virginia, and everywhere else,” he wrote.

Jeanie Ford, 58, a school bus driver, got vaccinated as soon as she could. But her sister, Bertha Roberts, 61, hadn’t yet — and somehow had escaped catching the virus, even after her grandson, 6-year-old Jasper, may have contracted it at after-school day care.

On Wednesday, Mills gave Roberts a shot.

Roberts said little but followed the conversation with her eyes, which widened when she learned Mills would be back to give her another jab in 28 days.

Across town, Randy Vaughan, a 96-year-old World War II veteran who served in the Navy, said getting vaccinated wouldn’t change much about his life because he gets few visitors, but he welcomed Mills and Burke nonetheless.

“My friends have about all gone ahead of me,” he said. “I don’t have any way to go anyplace anymore.”

Mills and Burke noticed his daughter asleep in an adjoining room and asked whether she needed a shot, too. Mills knocked on her door, but she didn’t stir.

“If you happen to talk to her and she wants the vaccine, we can come back and give her her vaccine as well,” she told Vaughan.

A metal ramp led to his front door, and a chair lift was fixed to the stairs near a large American flag and bronze sculpture of a soldier with the words “honor and bravery,” a gift from his granddaughter.

He used to hike the nearby national park trails until arthritis sidelined him a few years ago. An appointment to address a still swollen eye was canceled a year ago because of the pandemic and hasn’t been rescheduled, but he said it didn’t hurt — and neither did the shot.

“It wasn’t bad at all,” he said.