Two-legged, four-legged, six-legged or eight-tentacled … we're all in this together.
 |
| David Ollier Weber |
The little girl was 2 years old and suffering from a condition rarely encountered in human beings: congenital portosystemic shunt. It's a vascular abnormality that allows blood from the intestines to bypass the liver, thus escaping the filtration process that protects the body against the circulation of toxins. Confronted with this unusual and potentially fatal birth defect, the surgeon duly prepped by searching the medical literature.
Geraldine B. Hunt, B.V.Sc., Ph.D., is an Australian veterinary surgeon and a visiting professor at the University of California, Davis. She's also an expert on surgical intervention to correct congenital portosystemic shunt, which is fairly common among dogs and cats. In his reading, the surgeon had come upon papers Hunt had written in veterinary journals about the condition. He contacted her a few weeks ago for advice.
"We operate on our dog and cat patients quite regularly," Hunt explains in an e-mail, "and the surgeon and I discussed different treatment options based on my experience in dogs and the published veterinary literature. He decided that interventional radiology using transvenous thrombogenic coils [a successful technique for treating dogs] might be the least invasive method, and would not require any additional approvals as they do it regularly for other conditions in people."
That's One Health in action.
Between animal and human medicine there is no dividing line—nor should there be. The object is different but the experience obtained constitutes the basis of all medicine.
That sentence from the pen of 19th-century German physician Rudolf Virchow, the "father of pathology," encapsulates a concept that is gaining momentum throughout the world—a recognition that fragmented, turf-delimited approaches to the maintenance of human, animal and environmental health has become a dangerously inadequate paradigm.
Fully 60 percent of all the infectious diseases now recognized in humans—some 1,461 at last count—are caused by pathogens that flit across species lines. Think of the menacing plague-of-the-week we shudder to read about in the popular press: swine flu, bird flu, mad cow disease, equine encephalitis.… Plague itself, which killed a third of the European population in the 14th century and still claims victims today, is transmitted from rats to humans by fleas. Biting ticks inject Lyme bacillus; deer mouse droppings exude hantavirus. From AIDS to SARS, microorganisms that infect wild animals mutate to sicken and kill the human species; three-quarters of all emerging new diseases, notes the American Veterinary Medical Association, are zoonotic—meaning transmitted from animals, a word coined by Virchow.
Then, of course, there's the issue of keeping food animals safe to eat. Hamburger beef may be tainted by E. coli, a chicken pot pie by salmonella, a farmed-fish taco by streptococcus, and more. Even as worldwide demand for animal protein is forecast to grow by 50 percent over the coming decade, animal populations are under increasing health and survival pressures. Global warming, deforestation, non-native plant invasions, species extinctions, drug-resistant pathogens ... we're all—fragile planet and vulnerable inhabitants—in this thing together.
Sir William Osler, the famed Canadian-born physician whose innovations over a long career helped transform modern medical education (he was a founder of the Johns Hopkins School of Medicine, where he introduced, for example, the residency), knew that well. He trained briefly with Virchow, and on his return to North America in 1874 became a professor not only at McGill Medical School but also at the Montreal Veterinary College (later the McGill Faculty of Comparative Medicine). Osler was an avid dissector of animals and humans in search of common contagions.
À la Virchow, he emphasized that the two disciplines are "one medicine."
In the 1940s, veterinarian James Steele, D.V.M., and virologist Harald Johnson, M.D., working together through the federal Centers for Disease Control, developed a vaccine against rabies in dogs and designed arthropod-borne disease control programs that have been implemented worldwide. Steele organized the first veterinary division of the U.S. Public Health Service, and in 1968, he was named assistant U.S. surgeon general. Today, the CDC counts close to 100 veterinarians in its ranks, working as epidemiologists, laboratory scientists, policymakers, researchers and surveillance experts in environmental and disease prevention and control. In 2007 the CDC established a new National Center for Zoonotic, Vector-Borne, and Enteric Diseases (ZVED). Who else to put in charge but a veterinarian?
"Veterinarians' educational background in basic biomedical and clinical sciences compares to that of physicians," explains Lonnie King, D.V.M., who recently surrendered the reins of ZVED to become dean of the Ohio State University College of Veterinary Medicine. "However, unlike their counterparts in human medicine, veterinarians must be familiar with multiple species, and their training emphasizes comparative medicine. Veterinarians are competent in preventive medicine, population health, parasitology, zoonoses and epidemiology, which serve them well for careers in public health."
Medical history is punctuated by major breakthroughs based on fundamental research by physicians and veterinarians working shoulder to shoulder. Yellow fever, anthrax and tuberculosis are among diseases that have yielded to these collegial efforts. In 1996 veterinarian Peter Doherty and physician Rolf Zinkernagel won the Nobel Prize in medicine for their key discovery of the mechanism by which the human (and animal) body's immune system distinguishes cells infected by viruses from its own healthy cells.
Describing interdisciplinary successes like these in an influential 1984 book entitled Veterinary Medicine and Human Health, the late UC Davis professor Calvin Schwabe, D.V.M., D.Sc.—"the father of veterinary epidemiology"—proposed a united attack on zoonotic diseases. He revived Osler's invocation of "one medicine" and the concept—frequently coupled with, or alternatively labeled by, the broader phrase "One Health"—gathered international momentum.
In 2007 the American Medical Association threw its weight behind the movement when its house of delegates adopted a resolution calling for enhanced collaboration between physicians and veterinarians in medical education, clinical care, public health and biomedical research.
"The challenges of the 21st century demand that these two professions work together," the AMA acknowledged.
Riding point on the initiative, the American Veterinary Medical Association established a task force which in 2008 issued a report outlining a program to promote co-equal, cross-disciplinary communication and collaboration among physicians and veterinarians, along with environmental scientists, public health professionals, bioengineers, wildlife experts and plant pathologists, among others. Called the One Health Initiative, its cornerstone recommendations for the United States included organizing a national One Health commission, devising a national One Health research agenda, adding key One Health targets to the Healthy Animals 2010 and Healthy People 2020 scorecards and strengthening ties between medical and veterinary educators and students.
In 2009 the journal Veterinaria Italiana devoted a special issue to papers endorsing and describing One Health undertakings by 53 authors from 12 of 26 countries in which influential supporters have rallied behind the concept. Researchers in Israel, for example, reported on successful cooperative projects aimed at preventing infectious zoonotic diseases, including tick-borne relapsing fever and avian influenza. Teams of physicians, veterinarians and microbiologists from the Hebrew University of Jerusalem's Faculty of Medicine and Koret School of Veterinary Medicine, the Israeli Defense Force and the ministries of health and agriculture were represented.
At UC Davis, one of many campuses in the United States where veterinary and health sciences programs are forging new bonds, the Wildlife Health Center under Jonna Mazet, D.V.M., brings together epidemiologists, disease ecologists, ecosystem health clinicians and some 50 other participating UC Davis faculty members from many disciplines working at the cutting edge of pathogen emergence and disease tracking around the world. In October 2009 the Wildlife Center, in conjunction with the Wildlife Conservation Society, the Wildlife Trust, Global Viral Forecasting Inc. and the Smithsonian Institution, was awarded up to $75 million in funding by the U.S. Agency for International Development to establish a global early warning system—called PREDICT—for emerging zoonotic pathogens that pose pandemic threat.
This year, alongside its prestigious medical and veterinary schools, UC Davis will open a college of nursing. Cheryl Scott, R.N., D.V.M., director of the One Health Project in the School of Veterinary Medicine, says plans call for nursing and veterinary students to sit side by side in certain classes and to cross-train where appropriate.
"We all have the same skills," declares Scott. "We have to start looking at health as a system, not as bits and pieces."
The chimpanzee was elderly and suffering from congestive heart failure. Veterinarians at the Los Angeles Zoo wanted a transesophageal echocardiogram to guide their interventional decision-making. Perhaps, they decided, the director of imaging at the nearby UCLA Cardiac Arrhythmia Center, Barbara Natterson Horowitz, M.D., would agree to perform it.
Intrigued, Natterson Horowitz accepted the invitation from her veterinary peers to attend the primate patient. "These are among the top doctors I've ever worked with," she now exclaims. "Patients in our zoo hospital get much superior care in some ways than people who go to many community hospitals. Vets are extraordinarily capable."
Thus began a long-standing relationship that today sees Natterson Horowitz visiting the zoo—sometimes in the company of colleagues from other UCLA Medical Center departments—whenever a cousin in our biological order requires diagnosis or treatment of a heart condition.
"I was personally impressed by the remarkably shared cardiac physiology, even in the pathological state [of chimpanzee and gorilla and human hearts]," she says. "The fundamental structure, even the crux of heart [the cross-shaped intersection of the four chambers of the primate heart], is indistinguishable between them. For me that was an 'aha' moment. I'm looking at practically the same images in the morning at UCLA and in the afternoon at the LA Zoo."
Indeed, Natterson Horowitz now routinely displays images of animal hearts when she lectures students, interns and residents at UCLA Medical Center. Understanding evolutionary biology—how, for example, reptilian hearts function with a single ventricle and what that might imply for treating congenital human heart defects—"adds a dimension, a new perspective in comparative anatomy and pathophysiology," she says. It enlarges medical education and expands human physicians' frame of imaginative reference.
That's One Health in action.
David Ollier Weber is principal of The Kila Springs Group in Placerville, Calif., and a regular contributor to H&HN Weekly.
More information about the One Health Initiative is available online at www.onehealthinitiative.com.
This article 1st appeared on January 25, 2010 in HHN Magazine online site.
To respond to this article, please click here.
 |
|
Copyright ©2010 Health Forum. All rights reserved. H&HN is published by Health Forum, Inc.
an American Hospital Association information company. |
