Ashley Vick had never heard of a working hospital inside a ship. But the 26-year-old nurse was intrigued when she discovered the website of Mercy Ships while exploring opportunities for meaningful volunteer work.

Launched 40 years ago as a Christian ministry, Mercy Ships operates the world’s largest private hospital ship, docking it mainly off the coast of poor African nations and offering free critical surgeries to local residents.

Vick, of Lakeville, filled out an application to be a volunteer pediatric nurse. Last month, she stepped aboard a vessel that’s like a small city in the port of Douala, Cameroon. She spends her days providing medical care to children requiring surgeries for everything from cleft lips to tumor removals.

“This has been nothing like I could have imagined,” wrote Vick in an e-mail from her dorm room this week. “When I went through orientation, they said that we have 38 countries represented among the 450 crew members. So I have had the opportunity to meet and learn from people all over the world.”

It turns out that Vick is one of 10 Minnesota volunteers on board, including a dentist, dietitian and lab technician, Mercy Ships officials said.

The volunteers are enjoying a unique faith-based opportunity. Mercy Ships, based in Garden Valley, Texas, has offered ship-based hospital care in 55 developing nations around the world since its founding in 1978, said Pauline Rick, a spokeswoman for the nonprofit.

More than 2 million people have received medical care, training and other services, Rick said. The need is great.

“As many as 5 billion people lack access to safe, affordable surgical and anesthesia services worldwide,” said Rick. “And less than 6 percent of all operations are delivered to the world’s poorest countries.”

The ship stays afloat thanks to a crew of volunteers who serve not just as health care providers but also as engineers, accountants, cooks, plumbers and more. They live on a ship the length of a city block, with a bank, post office, cafe and lending library. Their volunteer stint varies by the job they hold.

Vick, a nurse at the University of Minnesota Masonic Children’s Hospital, is serving seven weeks on board. She shares a small room with several other volunteers, but she is able to head to Douala and neighboring areas during her time off.

Vick said she was attracted to the way Mercy Ships links its medical work to its Christian mission. Like many millennials, she is looking for ways to do good in the world, but often in nontraditional ways.

“I’ve been trying to advance my faith and feel closer to God,” said Vick, a lifelong Lutheran. “This allows me to do that with other people who are in the same boat — literally and figuratively.”

She marveled that everyone she’s met “is here because they truly feel called to help others.”

They’re also getting a crash course in global health care, including metric conversions and cultural differences.

“Tomorrow I’m going to the lab on the ship to get my blood screened so I can be eligible to donate to a patient if needed,” she said. “The awesome thing is we get to meet the patient after they receive it.”

Vick said she’s been struck by the gratitude of the families served.

“They have never-ending trust in the care we provide,” she wrote. “This thankfulness not only comes from the patients, but their families and the communities as a whole. On land, everyone greets us by shouting ‘Mercy Ships!’ and waving. “

Said Vick: “I have never felt so appreciated before.”