One-health wonders

Barbara Natterson Horowitz, MD, is a cardiology professor at the University of California-Los Angeles and the director of imaging (electrophysiology) for the Cardiology Division at the David Geffen School of Medicine at UCLA. Over the past several years, she has provided imaging and consultative services to the veterinarians at the Los Angeles Zoo, and through this, has become involved in the one-health movement.

In June she presented a one-health grand rounds to the UCLA community. Her emphasis on developing clinical collaborations between the worlds of veterinary and human medicine has attracted much interest over the past several months.

How did you come to be a practitioner of "one health"?

Performing echocardiograms on human and non-human primates has been extraordinarily gratifying. The really brilliant and forward-thinking veterinarians at the LA Zoo forged this alliance with human doctors. They have reached out to medical resources in the community, particularly the academic medical centers of Los Angeles, for expertise and input.

One such project involved the tamarins at the zoo. Several tamarins had died of heart failure, and the veterinarians had an idea that screening the animals with echocardiograms could identify patients at risk. In turn, these patients could be started on appropriate medicines to arrest the progression to heart failure. I assisted them with this project, performing echocardiograms and providing guidelines to them for the management of reduced ejection fraction, or cardiac function, in patients at risk for heart failure.

When another tamarin died, the veterinary pathologist and a human cardiac pathologist reviewed the postmortem. Indeed, both pathologists felt fibrosing cardiomyopathy was the cause of death. It was Dr. Michael Fishbein, the chief of cardiac pathology and my colleague here at UCLA, who told me that I was practicing clinical "one health." Prior to this, I had not heard of the term or the field, although I had been working in both the human and veterinary fields for some time.

Given this interest from the human area and the openness of veterinarians to collaboration, I think the timing couldn't be better for the development a clinical arm of the one-health movement.

— BARBARA NATTERSON HOROWITZ, MD, CARDIOLOGY PROFESSOR, UNIVERSITY OF CALIFORNIA-LOS ANGELES, AND DIRECTOR OF IMAGING (ELECTROPHYSIOLOGY), CARDIOLOGY DIVISION, DAVID GEFFEN SCHOOL OF MEDICINE, UCLA

Through my work at the LA Zoo, I began realizing how incredibly similar the diseases and pathologies were between species. Every day as a human cardiologist at UCLA, I would keep track of every disease I saw in a patient that day, whether cardiovascular, hematalogic, neurologic, gastrointestinal, or psychiatric. Then, in the evening I would search for correlates in the animal world. With help from the librarians at the UCLA Biomedical Library, I have accessed multiple veterinary databases for review. The overlap is extraordinary—and although this may seem obvious to veterinarians—my physician colleagues have been extremely surprised and, in some cases, inspired by this revelation. The results of this search have profoundly changed how I look at my human patients and their illnesses.

In 2002, there was this "new diagnosis" that exploded into the field of human cardiology called takotsubo cardiomyopathy. Basically, it was fear-induced heart failure. One day at the zoo, we were working on an animal that had been restrained and was being sedated for an echocardiographic analysis. One of the veterinarians cautioned me that we didn't want to scare the animal, and he mentioned that it might develop what's called capture myopathy. It turns out that capture myopathy was described in 1974 in Nature. The notion that intense fear can induce myopathy has been well known to veterinarians and occurs in multiple species. What's so fascinating about the literature is that it was decades later that we human cardiologists described it.

This recognition demonstrated to me the need for some form of clinical "one health." I thought, if this revelation occurred incidentally because a human cardiologist happened to be paying attention in a veterinary case, how many other diagnoses are there that are well-known in the veterinary world that we don't really know about in the human world because the language is different, the nomenclature is different, the terminology is different?

How would you like to see this knowledge shared across fields?

I have come to the firm conclusion that there would be great benefit to all species from collaboration not only in the areas of zoonotic infection and public health but even in the areas of clinical work and clinical research.

I also think there are many natural animal models of disease that human physicians are unaware of. As your readers know well, wild animals can develop heart failure and cardiomyopathy, breast cancer, leukemia, renal failure, and so on. I talk to my colleagues here who are cancer doctors, and most of them aren't aware of the incidence of breast cancer or ovarian cancer in domesticated and wild animals. So in some ways, "one health" is a call for a return or resurgence of comparative medicine, of comparative physiology.

We have an incredibly overlapping genome with primates and other animals. With this overlapping genome comes shared physiology and shared pathology. This is largely unknown information for most human doctors. "One health" has the potential to help how patients and their physicians think about their illnesses and could encourage them to develop more positive personal narratives about the causes and implications of their disease. In our society, everything is framed as "if you eat organic and you do this and you do that, nothing bad will happen." Well, some of these diseases are just shared in our common genome.

Are your colleagues in human medicine embracing the concept?

The interest and support in my work from my human physician colleagues here at UCLA has been fantastic. Everyone loves animals, and the notion of helping them through our training as physicians is very appealing. Since giving my "one health" grand rounds in June, I've had dozens of colleagues e-mail me to find if there is anything they can do to help the veterinarians at the zoo. Several of my colleagues were so glad to know that the results of clinical trials they had spent their lives working on were being used to help animals.

Given this interest from the human area and the openness of veterinarians to collaboration, I think the timing couldn't be better for the development a clinical arm of the one-health movement.