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Story Synopsis

In the lush mountains of western Uganda, tourists come to the dense forests in search of rare and exotic animals. What they don’t anticipate is coming in contact with some of the world’s rarest diseases.

That’s what recently happened to an American tourist who came down with a mysterious and deadly disease after visiting a cave known for its bats.

“We’re still not exactly sure how she acquired the infection,” says Dr. Stuart Nichol of the Centers for Disease Control and Prevention (CDC). “We know that she did enter the mouth of the cave but didn’t go very deep into the cave.”

A team from the CDC found that she’d contracted Marburg virus -- a hemorrhagic fever that causes extensive internal bleeding. Hers was the first case to reach the United States.

During the same period, another outbreak of hemorrhagic fever was devastating a remote village in the same region. It was discovered to be a new strain of the Ebola virus, which scientists believe was transmitted to humans who ate infected bush meat.

“Uganda is a really good example of a hot spot for where these diseases arise,” says Dr. Ali Khan of the CDC. “The infections due to animals represent 75 percent of all the emerging infectious diseases, and so if you’re really going to tackle these diseases, you can’t just focus on people. You need to focus on the animals, you need to focus on the environment, and on the interface where those come together to decrease infectious diseases worldwide.”

The Bwindi Impenetrable Forest lies on Uganda’s southern border. It’s home to half of the world’s remaining population of mountain gorillas, and it’s where Dr. Gladys Kalema-Zikusoka goes to work. She’s been studying diseases in the gorillas for 15 years and is known as the Dian Fossey of Uganda.

“I think what’s so special about the great apes is that they’re so similar to us,” she says. “We share over 98 percent of genetic material, with both gorillas and chimpanzees. And it means that we can learn a lot about ourselves by studying them.

“When you go to visit them in the wild, you actually feel like you’re connecting. They look at you. You look at them, and there’s some kind of connection. It’s actually very therapeutic watching them. And the infant gorillas are very playful, just like humans. When I see them playing, I think of my two children.”

Kalema-Zikusoka became Uganda’s chief veterinarian when she was 26. The BBC even made a documentary about her first year on the job. Nine months into her role as the country’s chief veterinarian, she was called to treat a family of gorillas that was suffering from a troubling new disease.

“Gorillas were losing hair and developing white, scaly skin. The baby gorilla had lost almost all its hair and was very thin. And the mother had also lost almost all of her hair where she was carrying the baby,” Kalema-Zikusoka recalls. “The baby was also making crying sounds, which is extremely abnormal for gorillas. I actually went and visited a human doctor friend of mine, because they could have picked it up from people. And she said it was scabies.”

Scabies is a minor skin infection for humans, but gorillas were new to the disease. For Kalema-Zikusoka, it was the first time she saw a human disease jump to mountain gorillas with fatal consequences. Recognizing this link between wildlife health and human health marked a turning point in her thinking. 

“It made me realize that you can’t protect the gorillas if you don’t think about the people living around the park, who have very little health care,” she says. “And because we’re so closely related genetically, we can easily get diseases from each other. The only long-term and sustainable method to improve the gorillas’ health is by improving the health of the people living around the park. And not just the people, but their livestock as well.”

Dr. William Karesh heads the Global Health Program at the Wildlife Conservation Society.

“When we say that there’s human health, or there’s livestock health, or there’s wildlife health, we just made that up. There’s only one health,” he says. “If animals are the source of a disease, we want to break the chain from people getting it. If people are the source of disease, we need to break the chain going in the animal direction.”

In 2002, Kalema-Zikusoka founded a nonprofit organization called Conservation Through Public Health, to tackle diseases that could be transmitted between humans, livestock and wildlife in the areas surrounding Uganda's national parks.

At a small village near the park, Kalema-Zikusoka works with the local community to teach hygiene -- in one case by showing a play about tuberculosis, a serious problem in Uganda.

“This is showing a good family and a bad family,” she explains. “The bad family threw rubbish next to the garden and defecated, and the [gorillas came and was] exposed to this. So then the good family, which is a man dressed as a woman, came in and cleared everything up. And told them off!”

Kalema-Zikusoka also volunteers to gather samples from villagers with chronic coughs, and makes sure that those who test positive for TB follow through with a full course of treatment. But there’s a problem with the local cattle as well -- they carry a strain of bovine tuberculosis that can sicken humans who drink infected cow’s milk.

“These cows could carry TB and pass it on to the humans, which would be a big shame in this community, because we are improving the overall health of the community,” Kalema-Zikusoka says. “So we’re going to carry out TB testing with the samples. And if there is any cow with TB, unfortunately it will have to be euthanized.”

She does all this because she knows how easily this disease could jump to gorillas.

“If the gorillas got TB, it would be a disaster,” she says. “TB requires treatment for eight months, especially in the forest setting. It’s easier for people to get that.”

What began a decade ago for Kalema-Zikusoka as an understanding that animal and human health are tethered together has become a new policy for organizations like the CDC. 

“We think of one health as not just about human public health,” Dr. Ali Khan of the CDC says. “One health is about human and animal public health, and, increasingly, what the strategy is telling us is we need to be working more closely in an integrated manner with the animal public health field.”

In Bwindi, Kalema-Zikusoka remains worried -- diseases far worse than TB have caused major die-offs in other primate populations. In the Congo basin, wildlife experts estimate that more than 5,000 lowland gorillas have died of Ebola over the last decade. 

“In Congo-Brazzaville, they’ve had people dying of Ebola who ate gorillas that died of Ebola,” she says. “They were very encouraged by what we’re doing in Uganda. And so now they’re trying to bring the wildlife authorities together with the public health authorities to address these issues.” 

Health authorities are also concerned about the further spread of these emerging diseases.

“Once upon a time, it would have taken days, weeks, months to go from one continent to another,” Dr. Kahn says. “Nowadays, within 24 to 48 hours, you can travel from one place to the other place, and still be incubating the disease. So it’s very easy to transmit diseases worldwide.”
"Sometimes it gets frustrating when you’re trying to promote conservation," says Kalema-Zikusoka. “There are so many other pressing issues. But what gives me hope is that, by promoting conservation, we’re improving community public health around a very remote area of Uganda.”

share your reactions

Daryl Hernandez
Chicago, Illinois

As I watched this excellent story and topic of man's health being inter related to animal health & the One Health concept ?

I am hoping to discuss further ideas here in our Housing Administration this concept of One House as it may relate to helping us solve homelessness & our apparent housing crisis. They too are inter related? Can we solve them as well using same strategic idea as One Health and One House?

Titus Apangu
Arua, Uganda

Bravo Dr Kalema for this great job! Keep it up.This is definately another turning point for more public health policies for communities living around the Game parks and forests reserves in Uganda.

Frank Mwiine
Kampala, Uganda

Gladys, this is great to tell your story otherwise nobody will. I remember watching your documentary aired on BBC as a young undergraduate vet in the 90s, and you were a great inspiration to most of us in Uganda and beyond the borders. Your tireless work in the field and research articles tell it all, from Brucellosis, Tuberculosis, Foot and Mouth Diseases Virus in buffaloes in western Uganda to conservation through public health issues. I consider you an ambassador of vets from the great lakes region to the rest of the world. The sky is no longer the limit. One world, one health is the concept, and it's the beginning. Let us, burn our candle and the rest of the world can see light.

Dr. Frank N. Mwiine, Uganda (BVM, MVPM, PhD fellow)

Augustine Amenyah
Athens, USA

This page was sent to me by Professor Stewart of Georgia State University Institute of Public Health. Thanks Dr. Kelema for eloquently bringing this issue to the attention of others in Public Health. I think through your great work all African countries should establish policies on animals and Public Health, an area often forgotten.

Thomas Stanley
Los Angeles, California

This was an important story. The encroachment of the growing population through new villages, agriculture and herding combined with the need for protein in the form of bushmeat creates substantial challenges to the disappearing wildlife. Village education is important. But also, shifting the roles of many of the men in the villages is important. Many villages receive their esteem by being considered great hunters. To shift that role to being "protectors" of the gorillas and other endangered species, has been successfully implemented on small scales in Namibia and other countries. Also, ensuring that local villagers profit from the economics of tourism and wildlife conservation will also assist in this effort.

Adam Margolin
Denver, Colorado

Frontline has provided a revelation regarding the dangers of Marburg Virus. In addition, it has provided conformation of traits that are well known to those of us who are connected with her: Michelle Barnes is an incredibly powerful woman to have survived Marburg.

Immaculate Nabukenya
Kampala, Uganda

Well done Gladys. There are so many otherwildlife vets in Uganda that deserve recognition as well; those who have cracked down the ebola virus source and provided info useful in treatment. Such are a big booster to saving the ecological diversity and ensuring action in the "one world, one health" concept. Cheers.

Ava Fuqua
Colorado Springs, CO

Finally the concept of "One Health" is taking the forefront. We are all connected. Keep up the great work!

Paul Langner
Alamogordo, New Mexico

As a veterinary student (U of PA, 1966) you quickly become aware of what are termed "zoonotic" diseases-transmitted from animals to humans. Because we are so far removed from rural or sylvatic environments in this country, we don't encounter diseases like tuberculosis from cattle or salmonella from poultry.

As a primate clinician, one is acutely aware of the respiratory viruses and bacteria, particularly TB, which are transmissable from humans to monkeys and apes. As we become aware of infectious diseases in general-now it's the H1N1 Flu, we begin to see the possibilities for transmission more clearly. If you count the diseases transmissable between humans and nonhumans in any comprehensive communicable disease text, you will be suprised at how great a majority these represent.

Think about the possibilities in poverty-stricken human communities without sanitation or vermin control and you realize how fortunate we are to be among the socioeconomic group which reads these articles.

Keep up the good work!

Katie Losey
New York, New York

Dr. Gladys Kalema-Zikusoka did an excellent job at showing the link between animal and human health and how this inevitably will affect us all. Her brainchild, Conservation Through Public Health, uses this "One Health" approach to conserve Uganda's gorillas and improve the lives of=
its people. Incredible work!

New York, New York
Dr.Kalema-Zikusoka did an incredible job demonstrating the connection between human and animal health, supporting the notion of "One Health". Her brainchild, Conservation Through Public Health, takes a unique approach to gorilla conservation - helping both Africa's people and its wildlife.

Kampala, Uganda
All these stories are amazing and the world at large needs this Information and thanks for this work.
I am Ugandan. I live and study Masters of Science in Environment and Natural Resource Management but its just of recent that I have started understanding my own environment and the Ecosystems' health and the possible threats.

Am sure very few Ugandans know about all this Info and the health implications of being in contacts with some ecosystem species like bats, monkeys and the apes.

Some People do eat them!

Basing on this Information, I am going to undertake a study research on ecosystem health in such respective areas in Uganda and I think my findings will help some Ugandans and policy makers.

Thanks for educating me, I personally know Gladys Kalema. In fact she is the one who has sent me this page. She is doing great work down here. I thank her too. -

Frank Kling
Woodstock, Illinois

Greatly exacerbating the spread of disease is human encroachment on wildlife areas as a result of deforestation and the bush meat trade. This is ocurring due to Uganda's explosive population growth rate of 3.2%. As such, Uganda's population will expand from 33 million to 130 million by 2050.

Cindy Haq
Madison, Wisconsin

This was an excellent segment. I've visited many of these sites and am proud of the efforts and publicity of One Health from Uganda.

High Falls, New York
Great segment on public heath and emerging disease. The exploration of interconnectedness of public heath and cross species transfer of disease from human to ape and ape to human. Will use it teaching about the human immune system.

Karen Powell
Louisville, USA

What an interesting story. I was fortunate to have hosted Dr. Kalema in my home for several days many years ago while she was a young vet and was here in the states working at the North Carolina Zoo with Dr. Mike Loomis. It's amazing to see what people achieve.