That personal connection can last for years. A lot of these patients need multiple surgeries and they'll come back again and again as the ship returns.
The idea for all of this, set sail back in 1978, when Don Stephens of Texas started the charity he calls Mercy Ships.
Scott Pelley: So how did you find this ship?
Don Stephens: We found her in Denmark. She was a rail ferry...
Africa Mercy replaced three earlier vessels. And Stephens says that over 35 years, hundreds of thousands of patients have been aboard his ships.
Scott Pelley: Where does the money come from?
Don Stephens: We've got corporate sponsors that we couldn't do what we do without them. Secondly, by the crew themselves. We have a unique business model. We charge everyone for the privilege of volunteering.
Scott Pelley: And you pay them nothing?
Don Stephens: Everyone pays their own way.
Doctors, nurses and crew pay their own way with donations from home, mostly from churches. You're often reminded onboard that this is a Christian charity.
[Ali Chandra: God you are good.
Gary Parker: We pray for your protection over her.
Nurse: And we pray for a complete recovery.]
A charity that treats patients of any faith.
West Africa is a territory of tribes and the ship is a tribe unto itself. There's no help out here.
The crew drills for every emergency. It's a tight community. Many stay for years.
They raise their children in the ship's school, and return to America on vacation. Ali Chandra's been on board four years. Now, she's pregnant but she plans to stay.
Scott Pelley: I wonder do you think of this as a sacrifice that you're making?
Ali Chandra: No. Not at all. There's things I miss from home. I miss strawberries and I miss fresh milk. And I miss my family. Not in that order. You have no idea how awesome this life is. I get to see the world. And I get to take care of incredible people. And why would you wanna live in a house on land? This is way more fun.
Scott Pelley: You met your husband here?
Ali Chandra: I did. Yep. I am one of the Mercy Ships' romances. Not the only one.
Scott Pelley: Are there a lot of those?
Ali Chandra: They call it the Love Boat. Yeah.
Scott Pelley: Who calls it the Love Boat?
Ali Chandra: I know-- a lot of-- any of us who have found our-- our loves here.
She found Phil, a ship's electrician. Gary Parker met his wife, Susan, onboard. And they've raised Wesley and Carys in a 630 square foot cabin. Susan found out how long they were staying, on TV.
Susan Parker: Somebody had asked him the question, "How long do you plan to be here?" And Gary looked straight in the camera and he said, "I hope for the rest of my life." And we looked at each other and sucked in our breath. And we started a journey of adjusting our expectations from that point.
Scott Pelley: The first time you saw him after you saw the documentary, did you say--
Susan Parker: Yeah, I did. And he said, "You never asked."
Scott Pelley: You never asked...
The only life the kids have known makes them strangers back home.