JEFFREY BROWN: Scientific experiment with chimpanzees, it's been a subject of hope and debate for years. In recent months, the federal government has moved to limit some of the research it funds with chimps, but questions remain about whether it should occur under any circumstances.
NewsHour science correspondent Miles O'Brien has our look.
MILES O'BRIEN: There are no other animals quite like them, except us. They share 99 percent of our DNA, and it shows. They scheme, plot and fight. They care for their babies, and they grieve their dead. And they love a good game of catch, emphasis on good, as I discovered.
Queenie had little patience for my wild pitches.
WOMAN: Did you see her stomp her foot?
MILES O'BRIEN: She's very mad at me.
MILES O'BRIEN: I don't blame her.
Those very similarities are at the core of a heated debate over whether scientists should keep using chimpanzees for scientific and medical research. Do we owe our cousins something more?
Here, they say we do. Welcome to Chimp Haven near Shreveport, La., a 200-acre oasis of tall trees and hidden daily treats for about 130 chimpanzees. Haven co-founder Amy Fultz put me to work making a chimp Easter egg hunt of sorts.
They would eat termites this way, right?
AMY FULTZ, co-founder, Chimp Haven: In the wild, yes, and ants. And actually, the chimpanzees here at Chimp Haven have been fishing for fire ants. And they do eat the ants.
MILES O'BRIEN: It's kind of like Mexican food, I will bet, huh?
MILES O'BRIEN: In short order, the chimps were let loose, and the treats were clearly a hit.
Linda Brent is president and director of Chimp Haven. She will never forget when the first chimps arrived here in 2005.
LINDA BRENT, director and president, Chimp Haven: They just poured out of their indoor enclosure out into the forest, all of them. And they ran all the way down. Several of them stopped a couple times and just did this wide-eyed wonder that they were out here and kind of free, finally free.
MILES O'BRIEN: The chimps here sure have earned it. Most of them have lived hard lives as test subjects in scientific and medical research.
AMY FULTZ: Well, some of the chimpanzees when they first arrive are actually afraid to put their feet down on the grass.
MILES O'BRIEN: Really?
AMY FULTZ: Yes. They haven't had that opportunity and some of them will stick close to the cement and the wire mesh.
MILES O'BRIEN: That's all they known, in other words?
AMY FULTZ: Yes.
MILES O'BRIEN: Cement and wire mesh is all they have known?
AMY FULTZ: Yes.
MILES O'BRIEN: Take a look at Chris. This is how she spends her time outside, alone, clinging to a 17-foot-high concrete wall, apparently traumatized.
Over the years, scientists have put chimps in harm's way in the name of research that benefits humans. They played a key role in the early days of the space race, the hunt for a polio vaccine, and, later, treatments for HIV and hepatitis as well. But, in recent years, Japan, Europe and the U.K. have all ended the practice, leaving the U.S. and Gabon the only two nations that allow scientists to conduct tests on chimpanzees, but maybe not for long.
JEFFREY KAHN, Johns Hopkins University: If this committee had been tasked to do what it was asked to do five years from now, we probably would have said there is no longer any need for the use of chimpanzees.
Much of how we came to talk about ethics in public health was informed by sort of the bioethics approach.
MILES O'BRIEN: Jeffrey Kahn is a professor of bioethics at Johns Hopkins University. He chaired a blue-ribbon committee for the Institute of Medicine that took a hard look at chimpanzee testing in the U.S. as the outcry from animal rights activists reached a crescendo.
JEFFREY KAHN: We did acknowledge that, from the perspective of this committee, the fact that chimpanzees are very close to humans gives them a different status.
MILES O'BRIEN: In late 2011, the committee laid out strict guidelines for chimp testing. The research must be done only when it's lifesaving, it can't be done ethically in humans, there are no other models, and the animals are socially and humanely housed.
When the report arrived here at the National Institutes of Health, they embraced the new rules almost immediately and formed a working group to examine the 40 research projects that currently rely on chimp testing.
James Anderson oversees that group.
JAMES ANDERSON, National Institutes of Health: But the first task of this working group is to review all of those one at a time, and hold them up against the IOM principles and say -- and tell us this is consistent or this is not consistent. And if they're not consistent, then we will work with the investigators to close down the project.
MILES O'BRIEN: When the new rules are applied, there are very few research projects that make the grade. And most of them have something to do with the hunt for a vaccine for hepatitis C. Right now, chimpanzees are the only laboratory animal that can be infected with the virus, although it doesn't make them sick.
ROBERT LANFORD, Texas Biomedical Research Institute: I do appreciate the sentiment that goes with chimpanzees. I feel it. I go home and say, are we still on the right track? Are we still doing the right research and is it absolutely required? And I come back and I say, yes.
So, which gene have you been cloning recently from the marmoset?
MILES O'BRIEN: Robert Lanford is a scientist at the Texas Biomedical Research Institute, where they house about 3,000 primates that are used for research, baboons, rhesus monkeys, and about 150 chimpanzees.
Sabrina Bourgeois is one of the people here whose sole job is ensuring the chimpanzees are healthy and happy.
SABRINA BOURGEOIS, Texas Biomedical Research Institute: I would say absolutely some of my best friends are chimpanzees, for sure.
MILES O'BRIEN: Really?
SABRINA BOURGEOIS: On a bad day, I absolutely come and seek out my friends.
Oh, you don't want it? You want something different?
MILES O'BRIEN: The attention, toys, push-pops and primate friends make it all seem like Chimp Haven. But there was an awful lot they wouldn't let us see here. None of these chimps are in the midst of a scientific study. We drove by the compound where that happens, but we were not allowed to go inside, much less record video of any active research or medical procedures.
MILES O'BRIEN: Is there something we're not seeing here that you'd rather us not see?
ROBERT LANFORD: It's not that we're trying to hide something. It's that we have a mission here that is to prove -- improve human health care. And we believe that when people see that picture, they can't listen to the mission anymore.
WOMAN: We were allowed to watch one of Lanford's experiments.
MILES O'BRIEN: Maybe so. Our trip did come on the heels of an NBC News report which showed this: one chimp getting sedated, blacking out and crashing to the ground, and another getting blood drawn while unconscious on a table.
And take a look at this dramatic video of a sedation at another research facility. This came from an undercover investigation by the Humane Society.
ROBERT LANFORD: They see that, and their empathy as a human automatically goes out to that animal and says, this doesn't look good.
MILES O'BRIEN: So is it cruel or not? Well that depends who you ask.
Sabrina Bourgeois is unequivocal.
So they're not suffering?
SABRINA BOURGEOIS: No, I don't believe -- I couldn't work here if they were. I really couldn't. I genuinely care and love these animals. I think a lot of us wouldn't be here, the majority of us would never be here, those who work with animals wouldn't be here if they suffered.
MILES O'BRIEN: But they do endure repeated sedations and biopsies. Medical files uncovered by the Physicians Committee for Responsible Medicine tell some grim stories.
Take Rosie, for example. At 30 years old, she has endured 15 liver biopsies, multiple blood draws, and 99 sedations, several resulting in seizures. And she is still a test subject currently at Texas Biomed.
Andrew Rowan is chief scientific officer for the Humane Society.
ANDREW ROWAN, chief scientific officer, Humane Society: Yes, they are suffering. And then the other thing about it is, the biopsies are not benign. I mean, the chimps that were retired out of this one lab in New York, they died 35. They can live to be 55, 60 years of age.
MILES O'BRIEN: But does the end ever justify the means? Scientists are using chimpanzees to battle a raging epidemic of hepatitis C. Fully 3 percent of the world's population, approaching 200 million people, carry the hep-C virus. The drugs used to treat it are not always effective and carry horrible side effects. And there is no vaccine.
DR. EUGENE SCHIFF, University of Miami: Arthur, nice to see you.
MAN: Hey, Dr. Schiff. Good to see you.
MILES O'BRIEN: Arthur, who asked us not to use his last name, believes he contracted hepatitis C during his days as a paramedic. He now has chronic liver disease and has suffered fatigue, nausea, irritability and depression from multiple drug treatments.
MAN: It's an insidious disease. And it's one that multiplies and grows, me, for example, having a very mild case of inflammation of the liver and, within a 10-year period, it progresses to cirrhosis.
MILES O'BRIEN: Eugene Schiff of the university of Miami, is Arthur's physician. He has been in the trenches treating hepatitis patients and researching the disease for decades.
DR. EUGENE SCHIFF: Now, I think I would be a hypocrite if I said we don't need the chimpanzee, and I think I would be doing a disservice to mankind.
MILES O'BRIEN: On his desk, he keeps a statue of a famous research chimp named Daphne. Testing on her helped scientists discover the protease inhibitors that make life a little easier for the likes of Arthur.
MAN: There isn't a day that I don't give thanks to Daphne for the gift that she gave me.
DR. EUGENE SCHIFF: And, indeed, the chimpanzee was the hero of hepatitis, because you could produce all of the viruses for hepatitis in the chimp.
MILES O'BRIEN: Scientists say they are close to a less morally fraught alternative to chimpanzees. Labs in New York and Maine are breeding so-called humanized mice, which have livers that can be infected with hepatitis C.
But this alternative won't be a reality for at least five years. Meanwhile, a moratorium on breeding lab chimps began in 1995, so, eventually, the testing will end, or will it? Some say we should keep a colony at the ready for diseases we can't predict. The government is expected to decide on that later this year.
LINDA BRENT: And this is what we could build at Chimp Haven.
MILES O'BRIEN: Wow.
MILES O'BRIEN: Really two-thirds again as much, right?
LINDA BRENT: Right. Right.
MILES O'BRIEN: Even so, with 1,000 chimps still in U.S. research labs right now, Linda Brent is making plans for expansion.
You're going to have a lot of potential visitors here, right?
LINDA BRENT: Right.
MILES O'BRIEN: Excuse me -- not visitors.
LINDA BRENT: Residents.
MILES O'BRIEN: Residents.
MILES O'BRIEN: How's that all are going to work out for you?
LINDA BRENT: Well, we're really excited about it. I think, in the very near future, we will be able to probably say that we have taken care of the chimpanzees that have served in medical research by giving them a fitting retirement.
MILES O'BRIEN: All right, you ready? You ready?
And, hopefully, an occasional pitch in the strike zone.
AMY FULTZ: Oh, yes, yes, yes.
JEFFREY BROWN: It's Science Thursday on our website. There, we have more on Chimp Haven, where there's something of a baby boom under way, thought to be due to males whose vasectomies actually repaired themselves.