What’s New About “Zoobiquity”?

 I just finished reading my copy of the new book Zoobiquity: What Animals Can Teach us about Health and the Science of Healing, by Barbara Natterson-Horowitz and Kathryn Bowers. It is a ground-breaking book and essential reading for anyone interested in the connections between human and animal medicine. The authors illustrate, through a large number of side by side comparisons, the striking parallels between clinical conditions in animals and humans, and what these similarities can suggest about the root causes of disease (including evolution and environment) and how best to treat them. Readers familiar with “One Health” concepts will find in the book vivid examples of the convergence of human, animal, and environmental health in emerging infectious diseases and animals as sentinels of toxic and infectious hazards in the environment. Yet, it is worth focusing on some of the truly innovative aspects of this book. First, Zoobiquity boldly asserts that by neglecting its comparative medicine roots, clinical medicine itself has gone astray and the medical profession needs to use the perspective of clinical science that spans different species to get back on track. We need to understand mental health problems such as addiction and self-destructive behaviors in the context of evolution and environment, just as naturalists and veterinarians strive to do, and use this perspective to design new treatment and prevention approaches. Similarly, we need to use the same tools of evolutionary and environmental understanding to rethink our approaches to chronic diseases such as obesity and cancer. Second, Zoobiquity builds the strongest case to date for greater development of clinical knowledge of animal health using techniques that are driving evidence based medicine such as randomized trials and large observational cohorts followed over time in order to glean important information useful for both animal and human health. Third, the concepts in Zoobiquity are presented so clearly and documented so extensively that they appear to have struck a chord in both the general population (see Oprah’s 2012 summer reading list) and the medical community that propels the discussion of human animal medicine linkages to a whole new level. Overall, Zoobiquity throws a gauntlet out to the biomedical scientific and clinical community, urging it not to delay further, but instead to set up an effective research and development infrastructure to pilot and test new hypotheses and clinical approaches using this enhanced comparative model It will be fascinating to see who comes forward to accept this challenge.

Human Health Care Providers and Veterinarians Need to Communicate

It is not uncommon for patients to ask me whether an illness in a pet could be related to symptoms they are experiencing. For example, a patient suffering from allergies caused by mold in her house told me about her dog that was being treated by a veterinary allergist. Was it possible that human and dog were dealing with the same problem?

What are physicians or other health care providers supposed to do with such questions and information? Physicians receive no training in veterinary diseases and are not taught how to appropriately respond to these issues. Should a doctor ask more questions about the dog’s illness? Ask to speak to the veterinarian? Is this a useful line of inquiry or mere frivolous waste of time?

Over 60% of U.S. households include at least one pet (Hoff1999), and this proportion is increasing. Often the degree of medical care that the pets are receiving equals or exceeds the medical care happening for humans in the household. There is a basic rule that veterinarians are not allowed to treat human patients (but veterinarians tell me that their clients often ask for medical advice about zoonotic diseases and other conditions). Physicians, for their part, are not supposed to diagnose or treat animals (but tell that to the rural family doctor I met this week who is regularly asked to take care of goats and cows and dogs). At the same time, there are growing similarities between veterinary medicine and human medicine. (Rabinowitz and Conti 2010) Both disciplines use similar blood tests, urine test, and radiological studies to diagnose disease. Both use similar (but not always identical) medications to treat infections, diabetes, and even mental illness. And there can be value in seeing the numerous similarities between medical conditions that manifest in an animal and a human, as physicians such as Barbara Natterson have noted (see her zoobiquity website http://www.zoobiquity.com )

There are a number of specific reasons why physicians and veterinarians need to communicate and collaborate. Contact with pets or other animals can increase the risk of zoonotic (animal to human) disease transmission, especially for children and immunocompromised individuals (Pickering et al 2008, Kaplan et al 2009, NASPHV 2011), and veterinarians can contribute to effective prevention of such transmission. Veterinarians can also work with clients to reduce the risk of animal bites from pets. Beyond the risk of infections and injuries, people may share chronic health problems such as obesity with their companion animals, and be willing to engage in joint preventive behaviors such as exercise programs (Kushner et al 2006). The strength of the human-animal bond may affect psychosocial health, as well as access to medical care (for example; a patient unwilling to leave pets at home to go to the hospital). Drug-seeking patients may request pain medication and other controlled medications from veterinarians on the pretense that it is needed for their pets (LeBourgeois et al 2002).

In addition, illness in an animal may be a “sentinel event” indicating environmental risk for humans (see the Canary database www.canarydatabase.org for more information on this). An example would be allergies due to a common allergen in the environment, or a dog that is diagnosed with a tick-borne disease giving warning about risk to humans who walk  in the same suburban areas as the dog.

Despite all of these apparently obvious reasons for communication and collaboration between veterinarians and human health care providers, real life examples appear to be rare. The practice of medicine is increasingly evidence-based (as it should be), and the lack of published studies documenting the benefit of such encounters between professionals makes it hard to change current practice patterns. At the same time, there are also no studies showing a lack of benefit of such teamwork! In other words, these ideas, however obvious and promising, remain virtually untested.

What are needed are good pilot projects and studies to begin documenting proof of concept of collaboration between human and animal health professionals. These studies could test the acceptability and effectiveness of clinical protocols and materials such as templates for referrals between veterinarians and their human health counterparts. As information begins to flow between the disciplines, the evidence will be able to point future practice patterns in the correct direction. I (and many others) will welcome that day.

References:

Hoff GL, Brawley J, Johnson K. Companion animal issues and the physician. South Med J. 1999; 92:651-9.

Kaplan JE, Benson C, Holmes KH, Brooks JT, Pau A, Masur H. Guidelines for prevention and treatment of opportunistic infections in HIV-infected adults and adolescents. MMWR Recomm Rep. 2009;58(RR-4):1-207.

Kushner RF, Blatner DJ, Jewell DE, Rudloff K. The PPET Study: people and pets exercising together. Obesity 2006;14:1762-70.

LeBourgeois HW 3rd, Foreman TA, Thompson JW Jr. Novel cases: malingering by animal proxy. J Am Acad Psychiatry Law. 2002;30:520-4.

National Association of State Public Health Veterinarians, Inc. (NASPHV); Centers for Disease Control and Prevention (CDC).Compendium of measures to prevent disease associated with animals in public settings, 2011: MMWR Recomm Rep. 2011 May 6;60(RR-04):1-24.

Pickering LK, Marano N, Bocchini JA, Angulo FJ. Exposure to nontraditional pets at home and to animals in public settings: risks to children. Pediatrics. 2008; 122:876-86.

Rabinowitz PM, Conti LA. Human Animal Medicine: Clinical Approaches to Zoonoses, Toxicants and other Shared Health Risks. Elsevier 2010; 432 pp.

High altitude cattle and comparative medicine

A recent article in the New York Times is a reminder of the potential for new approaches to comparative medicine outside of the typical research laboratory. For years, veterinary researchers have studied the effect of high altitude on cattle grazing in mountainous areas of New Mexico and elsewhere. These studies have revealed important findings about the chronic effect of hypoxia on the cardiovascular system, including insight into the condition of hypoxic pulmonary hypertension that is an important disease in humans. The researchers have also been able to study the effect of genetic susceptibility on these physiologic responses, and to develop clinical approaches for early diagnosis of altitude illness. The recent research reported in the Times actually builds on studies of high altitude cattle in Colorado and other parts of the Southwestern US that have gone on over the past 100 years. And while we have learned a lot about human pulmonary hypertension (a disease that develops in individuals with sleep apnea and other hypoxic conditions) from “Brisket disease” in cattle, there are also preventive lessons to learn from animals that are evolutionarily adapted to high altitude, such as certain types of llamas, rodents, and yaks. These adaptations can involve not only much thinner blood vessels in the lungs, but also a lack of the response to low oxygen that is seen in cows and persons who develop pulmonary hypertension.  These findings reinforce the fact that there is much to learn from studies of naturally occurring animal populations that can influence both human medicine, veterinary medicine, and our understanding of the effects of environmental factors on health.  

The Need for Evidence

Over the past decade, human medicine has become more “evidence based.” Under this paradigm, recommended clinical policies regarding prevention, diagnosis, and treatment of diseases should be based on explicit evidence of the value of a particular approach. For example, whether or not a patient should be started on a daily aspirin for prevention of heart disease should be based on studies of such an intervention, and a weighing of the reported benefit of the intervention versus both the risk and cost of the intervention. The push for evidence based recommendations has resulted in certain traditional treatment approaches being abandoned and new ones adopted.

When it comes to human-animal medicine issues, including the use of animals as sentinels for human environmental health hazards, the use of animal assisted therapy for certain medical conditions, measures to prevent zoonotic disease in animal workers, and even the potential impact of adopting a “One Health” approach to disease prevention in the developing world, the truth is that there is a relative lack of “high quality”  evidence (such as controlled studies) either supporting or not supporting such interventions. This of course does not mean that such approaches are not worthwhile or do not hold potential for enhanced treatment and diagnosis of disease affecting both humans and animals (there is abundant anecdotal evidence that it may). Rather it means that there is a real need for research to test and rigorously evaluate such approaches. The Canary Database is an attempt to bring together published evidence about animals as sentinels of human environmental health hazards. Users can see “summary screens” that provide preliminary summaries of the strength of evidence that for a particular environmental hazard, particular species of animals may be either more susceptible, show shorter latency between exposure and disease onset, or have greater environmental exposure compared to humans. Advocates of “One Health” should be willing to see the concept tested objectively, and use the results to better hone future efforts to integrate human, animal, and environmental health.  Conducting studies that search for such evidence will better justify the commitment of health care resources in a human-animal medicine direction.

Welcome to the Yale Human Animal Medicine Project blog!

We are excited to welcome you to the Yale Human Animal Medicine Project blog.  We hope to bring you informative and interesting posts on our current projects, new journal articles, and news in the world of zoonotic research. 

sciseekclaimtoken-4f6a252d5e1ce

For more information please visit the Yale Human Animal Medicine Project website, like us on Facebook, and follow us on Twitter.