Feb. 18, 2017
One Health: A unified approach to medicine
Billing itself as "a worldwide strategy for expanding interdisciplinary collaborations and communications in all aspects of health care for humans, animals and the environment," the One Health initiative is a more integrated and inclusive way of looking at health issues than the traditional “silo” approach.
“The concept of One Health is not new,” says Dr. Baljit Singh, dean of the Faculty of Veterinary Medicine at the University of Calgary (UCVM). “But now there is more explicit recognition that we could make more advances in understanding complex problems such as food safety, water safety, infection and disease transmission if we work together as a team and look at the whole ecosystem. It’s a set of principles that allows us to work together, to teach our students, do research in partnership with our communities to look at animal, human and environmental health in a single platform.”
That team approach is reflected at the University of Calgary with a wide range of interactions between researchers. For example, there are complex interdisciplinary research projects exploring drug-resistant parasites and simple, informal acts such as a scholar who studies kidney disease in cats joining doctors on their rounds with human renal patients.
Like human, like cat
People and their pets can have similar diseases and research into diabetes mellitus in cats may, one day, help humans. “Cats have several similarities to humans with Type 2 diabetes. One common similarity is a very strong risk of developing this disease with increasing body weight, just like in humans,” says Dr. Chantal McMillan, senior instructor in the department of veterinary clinical and diagnostic sciences, UCVM.
“Unlike dogs, a large proportion of cats can go into diabetic remission with appropriate therapy including daily insulin injections,” she says. “With remission they no longer require daily insulin injections.”
McMillan is working with Dr. Prasanth Chelikani, associate professor, department of production animal health and his PhD candidate Dr. Rizaldy Zapata, who are researching obesity and related disorders such as diabetes. This collaborative work may have significant implications for the prevention and treatment of diabetes in cats and possibly humans.
“Forty per cent of cats aged nine and above will develop some form of kidney dysfunction."
While rare in dogs, cats commonly develop kidney problems. “Forty per cent of cats aged nine and above will develop some form of kidney dysfunction, it’s certainly a problem,” says Serge Chalhoub, an instructor in the Faculty of Veterinary Medicine.
Products that have been developed to treat humans are working well with cats as well and conversely, understanding kidney disease in cats is helping develop treatments that can apply to people.
Chalhoub will often talk with doctors treating human renal issues, even joining them on their weekly rounds. “We look at a lot at human research for the work we do,” he says. “One area of research is renal anemia that develops with chronic kidney disease. In humans it’s a very well documented issue when it comes to quality of life.”
Things to remember:
- If your cat is drinking more, urinating more often and is losing weight despite eating, have your pet examined. It could have diabetes.
- It’s very important to keep your cat at a healthy body weight because overweight or obese cats are predisposed to diabetes and other health problems.
Helping people by studying drug-resistant parasites in livestock
One of every six people on the planet is infected with parasitic worms. These parasites cause a variety of disabling and debilitating conditions that the World Health Organization (WHO) classifies as “neglected tropical diseases.”
These human diseases are controlled by ivermectin, a drug that was originally developed to control
parasites in livestock but was repurposed to control human parasites in the developing world. One Health approaches like this are needed more than ever to help sustain and improve human parasite control.
In the last few years, WHO and other organizations (including the Bill and Melinda Gates Foundation) have ramped up the mass administration of anti-parasitic drugs in the developing world, leading to the threat of the parasites becoming resistant to the drugs.
“The agriculture industry has been using drugs to treat livestock infected with parasitic worms for decades,” says Dr. John Gilleard, associate dean (research) and professor of parasitology at UCVM. “Because parasites cost the North American cattle industry more than $2 billion a year, pharmaceutical companies have invested in research and drugs to address this.”
"The emergence of drug-resistant parasites is a real concern for public health."
Now, that investment has the potential to help improve human health. “With the recent increase in use of drugs to kill parasitic worms, the emergence of drug-resistant parasites is a real concern for public health in the developing world,” says Gilleard. “We are taking what we know about livestock to figure out how to detect, monitor and manage drug resistance in human parasites and look for new drugs to treat and control them.”
Gilleard and colleagues in the Faculties of Veterinary Medicine and Science, and UCalgary's Cumming School of Medicine, will apply molecular tests similar to those used in livestock parasites to detect drug resistance and also seek to identify new anti-parasitic drugs for use in both animals and people.
Things to remember:
- A One Health approach takes knowledge about parasites in livestock to help improve the control of human parasites.
- One of every six people on Earth is infected with parasitic worms and there is a concern the parasites are becoming resistant to the drugs used to treat them.
Lentils from Saskatchewan helping poisoned Bangladeshis
Bangladesh has the worst case of mass poisoning in history. In just one decade, from 2000 to 2010, 77 million Bangladeshis were exposed to arsenic that occurs naturally in their well water.
Deep-tube water wells were dug in the 1970s to prevent people getting sick from drinking contaminated surface water. But inadvertently, Bangladeshis are being exposed to arsenic, poisoning that can lead to cancer, skin lesions, lung problems, hypertension, diabetes, cardiovascular and central nervous system disorders. Arsenic poisoning is responsible for one of every 18 deaths in the densely populated south Asian country.
Lentils from Saskatchewan may help solve the problem in Bangladesh.
“These lentils are high in selenium, which can help reduce the arsenic in the body,” says Dr. Judit Smits, professor of ecosystem and public health at UCVM. “It’s the flipside of veterinarians historically using arsenic-based medications to treat cattle poisoned from eating plants with high levels of selenium.”
Here’s how it works: When both arsenic and selenium are present in an animal or human, the elements bind together in the blood and are less able to move into organs and tissues where they cause the damage. Instead, they’re excreted through the liver, digestive tract and the kidneys.
Smits and her team are beginning to see promising results from their three-year project, in which 400 people in about 80 families are eating lentils – some low in selenium, while others eat the Saskatchewan lentils that are high in selenium. Early results in the double blind study are showing one group is excreting more arsenic through the gut than the other.
“Eating lentils rich in selenium would be a much cheaper solution to the poisoning than having to replace the water supply,” says Smits. “It would also be simpler than trying to get millions of people to take selenium pills every day of their lives.”
Another potential benefit to this One Health research project would be encouraging a bigger and more selenium-rich lentil crop in a developing country. While Bangladeshis grow lentils now (a staple of the country’s diet) they are not high in selenium nor do they grow enough to feed the country.
Things to remember:
- Veterinarians have been using arsenic to treat selenium poisoning in cattle for decades. Now researchers are using selenium-rich lentils to treat Bangladeshis suffering from arsenic poisoning.
- Arsenic and selenium will bind together in the blood and be excreted instead of moving into organs and tissue where they can cause damage.
Pets and people
We share more than our homes with our pets. Researchers use knowledge they collect about hip replacement surgeries, treating diabetes and kidney disease to benefit both humans and our four-legged friends.
Hip disease in dogs is very common. It’s one of the most common reasons dogs suffer lameness and discomfort in their hind legs. The procedure for hip replacement surgeries in dogs and humans is similar.
Historically, implants were cemented into the bone but the cement can loosen over time resulting pain and lameness coming back. Newer implants and techniques move towards non-cemented or “press fit” hip replacement surgeries that provide potentially longer stability and fewer complications.
“We create a defect in the bone that’s slightly smaller than the actual size of the implant and press the implant into that defect through our surgical technique,” explains Dr. Terri Schiller, a small animal surgeon and associate dean (clinical programs) at UCVM. “The patient’s own bone grows into the textured surface of the implant and that interface holds that implant stable in the bone.”
These improved implants are generally expected to last for 10 to 14 years in dogs (their lifetime) and 15 to 20 years in humans.
“We keep our finger on the pulse of what’s going on in human total hip replacement in terms of changes in implant design, implant surfaces, different biomaterials,” Schiller says. “From that we may make design and implant changes for canine patients.”
Hip replacements for dogs have improved partly because of research using dog models to improve hip replacements for humans. “The spinoff of this research has been that we have developed better total hip replacement systems for dogs and humans," Schiller says. "Companies that focus specifically on dog hip replacements have arisen through this clinical research that really was aimed at solving human hip implant problems.”
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ABOUT OUR EXPERTS
Dr. Baljit Singh, PhD, is dean of the Faculty of Veterinary Medicine at the University of Calgary. His research has focused on cell and molecular biology of lung inflammation. View his profile
Dr. Chantal McMillan, DVM, is a senior instructor in the department of veterinary clinical and diagnostic sciences in UCalgary's Faculty of Veterinary Medicine. Her interests include all aspects of internal medicine, particularly endocrine disorders of small animals.
Dr. John Gilleard, PhD, is associate dean (research) and professor of parasitology with UCalgary's Faculty of Veterinary Medicine. He is cross-appointed in the Department of Biochemistry and Molecular Biology in the Cumming School of Medicine, and holds a visiting professorship at the University of Glasgow. His research interests are in the field of drug resistance in parasites. View his publications
Dr. Judit Smits is a professor of ecosystem and public health in UCalgary's Faculty of Veterinary Medicine. Her research interests are founded in ecotoxicology and the impact that environmental contaminants have on human and animal health. View her profile
Dr. Terri Schiller, DVM, is a board specialized small animal surgeon and Associate Dean (Clinical Programs) at UCalgary's Faculty of Veterinary Medicine. Her clinical practice focuses on the delivery and teaching of small animal orthopedic surgery and canine total hip replacement. View her profile
Dr. Serge Chalhoub, DVM, is an instructor in UCalgary's Faculty of Veterinary Medicine. His research interests are in clinical nephrology/urology and interventional medicine. View his publications