One Health—The Book

New Book on One Health

I wrote a book. Actually, I co-wrote a book.  The book, published by Wiley in January 2019, is Introduction to One Health: An Interdisciplinary Approach to Planetary Health ( Parts of the book are open access, including the first chapter in which the two other authors and I use our home base in St. Louis, Missouri, situated on the bank of the Mississippi River, as an example of the One Health challenges and opportunities that flow through our past, present and future. Try it out

We divided the book into 6 sections, including (1) An Introduction and Impetus for One Health; (2) The One Health Triad; (3) Practitioners and Their Tools; (4) How to Start a Movement; (5) Humanities of One Health; and (6) Where Do We Go From Here. These sections are further divided into 15 chapters, in which we seek to answer the what, where, when, why, who, and how of One Health.  Science at the core, we include interviews of persons across disciplines showing the diversity of career choices necessary to solve today’s health challenges and case studies of real life One Health challenges and opportunities. We also use storytelling as the vehicle for inspiring next-generation planetary health care-givers. The foreword, written by Dan Ashe, CEO and President of the Association of Zoos and Aquariums, starts the book off with his take on why we need biodiversity and how One Health will help us continue to have a planet full of life, and one worth inhabiting, as the 21st Century unfolds. 

Why a Book on One Health

I am often asked why write a book on One Health?  The answer is easy and one I counter with questions of my own.  I ask whether the person has found her/himself increasingly thinking about the conservation and public health challenges that threaten human, animal, and plant health. I follow with a question on whether climate change or the loss of biodiversity or plastic pollution is on their mind. I then remind the questioner that all these, along with countless other, challenges have impacts on the health of life, whether animals living in the deepest oceans or humans living in the most crowded cities. These challenges threaten planetary health and the health of all life—One Health. 

A book like this is just in time.  With the growing body of evidence on the global challenges—even the biggest science deniers among us—must surely be thinking about the impacts they of these challenges on the health of their families.  The data on climate change and the impacts this has on all facets of our cultures, politics, economies, as well as health is a wake up call.  Climate change is real and it exerts impacts, both small and large, on all life. Then just this month, another report released, and frankly this one keeps me up at night and working hard during the day, should also move us to reflection. This is the UN report on the current state of biodiversity. Read it!  If not the whole report, at least the summary on the current state of the planet you call home

Both these documents are report cards of sorts, providing grades on the health of life on Earth today. These reports are connected. We know that climate change leads to biodiversity loss and that the loss of biodiversity has negative feedbacks on climate change.  They are indicators of our shared health concerns—One Health.

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One Health is About Hope

The story does not need to end here with us simply letting these challenges loom large, creating a type of overwhelmed apathy. Instead, these facts should generate energy, drive, and determination within us so we may come up with solutions.  This is the true value of One Health.  A solution based transdisciplinary approach to overcome the planetary health challenges we humans have created, and for which we humans increasingly will suffer.  One Health is about hope.  

In the same month of the UN’s alarming report on the state of Earth’s living creatures, with 1 million species of animals and plants at risk of extinction, there was other news.   Good news!  Jane Goodall, the icon of conservation and hope, received a Time Person of the year award.  Her words play out well in an interview Although not called by name, Goodall speaks of One Health and the responsibility and power we each have to help save wildlife, wildlands, and Homo sapiens alike.  A call to action. One of the easier actions might just be to sit down with a copy of our new book and learn about the what, where, when, why, who, and how of One Health. Then go out and save the world.     


The Ecological Footprint Challenge

Last year, I took a test. You might not think this is the best way to start a blog, but stay with me. The test I took is different. My students and I, during the One Health course I was co-teaching at Washington University in St. Louis, did a group activity and took a test. It was even “fun!” This test is one that everyone, including you, should take and that allows you to calculate your ecological footprint.

An Ecological What?

First, you may ask, “What is an ecological footprint?”  One definition for an ecological footprint is that it is a measure of the ecological assets (all those living species and non-living things that share the planet with us!) a given person or population requires if she/he/they are to continue living the same way as they are right now.

Earth Overshoot Day

In 2018, the estimated ecological footprint, based on the 7.6 billion humans alive that year, was 1.7 “Earths.” This resulted in Earth Overshoot Day 2018 to be on August 1st. In other words, by August 1, 2018, we humans used up the natural resources that were available to us, without damaging the planet or overdrawing on resources, when there were still 152 days remaining in the year. We overshot our resources. We borrowed 152 days from the next year. In fact, Earth Overshoot Day shows that humans use more from nature than could ever be replaced. In 1987, the first recorded Earth Overshoot Day was calculated to be December 19th. In other words, that year we had 12 days of 1987, from December 19th – 31st, when we were in overdraw of the Earth’s resources. The Earth simply could not keep up with the resources we were extracting. Since that first year of recording the timing of Earth Overshoot Day, the date keeps moving farther from December 31st. In 1987, it was calculated on December 19th, but in 2018 it was August 1st. By 2030, projections place Earth Overshoot Day on June 28th if we continue with “business as usual.” Not only is this not sustainable, it is also crazy!

However, as you may have guessed, not all of us are equal in the size of our ecological footprint. Calculations suggest that certain populations use far more than their share of the resources. That’s right you (probably) and me (for sure) use more than our share of Earth’s resources if we want to continue to have a planet habitable for humans and other living beings.  

What’s your Ecological Footprint?

Okay, back to you. Have you ever thought about your individual ecological footprint? When my class and I did it as a group, we came up with 6.2 Earths. When I did mine solo, I came out with 4.2 Earths. If everyone lived like me, we would need 4.2 Earths. I could not believe it. I live in a single car (Prius) family, I walk to work most days, I eat very little animal-based protein, and I gave up plastic straws long ago. It takes 4.2 Earths to keep me going. I wandered how many Earths it must take for just one Kardashian?

The beauty of calculating your own Earth Overshoot Day is that it can wake you up to the planetary cost of letting you … be you. Questions factored into the calculations include, but are not limited to: 1) How often do you eat animal based products? 2) How much of the food you eat is unprocessed, unpackaged or locally grown? 3) What is the size of your house? 4) Do you have electricity in your house? 4) How far td you travel each week by motorcycle or car? 5) How many hours do you fly each year? (This last one is the one that got me!)

I dare each of you to take this test.  If you have 5 to 15 minutes right now, the energy to think about your ecological footprint, and the desire to learn how to decrease this footprint, settle in and click on the link at

This one simply tool allows each of us to consider our ecological footprint and how we might decrease our individual footprint, from the easy to do things such as carpooling, non-fossil fuel based travel like bikes and legs, to recycling.  Then maybe it will stimulate each of us to see how we might help with the more challenging, but imperative, efforts for Planetary Health. We need to come up with the next technological advances in re-useable energies and sustainable food sources and environmental restoration mechanisms.   

Did you do it? Did you take the test? How many planets would we need if everybody lived like you? When is your personal Earth Overshoot Day? Mine was March 28th! Since I took the test, I have been working on ways to move my Earth Overshoot Day away from January 1st and closer to December 31st.    

Take the test! I guarantee it will have you thinking differently and more importantly, I hope acting differently.

7 Days at Alcedo Volcano

A second blog of our July 2018 trip of a lifetime. This one written and illustrated by trip photographer, Joshua Vela Fonesca. Joshua shares his artistic vision as the Galapagos Tortoise Movement Ecology Programme team (well - not the whole team. Steve and Anne were back on Santa Cruz Island!) works for tortoise conservation.

Joshua’s photography and words capture this magical week!


Find this month’s blog at

An Inconvenient Truth – Zoonotic Pathogens

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Animal to Human Pathogen Transmission

Most likely in the last year you have heard of at least one disease event caused by a  pathogen “spillover” from animals to humans. I would even venture if you have not heard of any zoonotic disease, you probably live in a bunker in Indiana. Coverage of these disease events has increased greatly in recent years as the frequency and types of human and animal intersections continue to escalate. Zoonotic diseases—those infectious diseases shared between human and non-human animals—are often significant and costly, in both the loss of human lives and impacts to the global economy. There are so many zoonoses that I could spend the rest of this blog playing “name that zoonotic disease” as I write out the 1,600 or so diseases that humans share with animals: many of which are emerging within human populations.

I might start the list with diseases like avian influenza and swine flu. Then I could mention the zoonotic viruses Ebola and monkeypox. These two viruses are extremely important, but for some reason feel exotic to people in the United States, even though people have tested positive to both while on US soil. One person even died of Ebola in a hospital in Texas in 2014. I might then list the oldest known zoonotic disease—rabies—and consider the fear it instills with the recent reminder following the tragic rabies related death of a child in Florida. Other zoonoses on the list may include West Nile virus, Sudden Acute Respiratory Syndrome (SARS), Middle Eastern Respiratory Syndrome (MERS), Zika virus, Q fever, and toxoplasmosis. The list would go on and on. In our globally connected world, any one of these diseases could show up anywhere on the planet, from Alabama to Zimbabwe. The often-cited statistics that 75% of human emerging infectious diseases (EIDs) are zoonotic and that 70% of these have a wildlife reservoir should be of interest to anyone that cares about human health. But, what about the other side of the equation? Do animals get infected with pathogens transmitted from people?

Human to Animal Pathogen Transmission

The simple answer is yes. Humans can and do transmit pathogens to non-human animals. Some call these diseases anthropozoonoses to reflect the human (anthro) to animal (zoonosis) direction of the transmission. However, I am much more comfortable to call these diseases zoonoses. The term zoonotic should include the diseases from non-human animals to humans AND from humans to non-human animals. Zoonoses may be bi-directional. However, even with all the current news on human EIDs and their zoonotic link, we rarely hear about pathogens that humans transmit to non-human animals.  

In a recent study ( ), we looked at the other side of the zoonoses equation and sought to determine if humans transmit pathogens to our great ape relatives. In the paper entitled “Pathogen Transmission From Humans to Great Apes is a Growing Threat to Primate Conservation” we provide data from a meta-analysis (a review!) of the scientific literature on great ape infectious diseases acquired from humans. We looked at great apes living in captivity, semi-free living conditions (such as great apes habituated for ecotourism) and free-living. We found 33 individual occurrences of probable or confirmed pathogen transmission from humans to great apes during the period 1964-2012. Occurrences were found in great apes in captive (n = 7), semi-free-living (n = 25), and free-living (n = 3) conditions, with two occurrences affecting populations in both semi-free-living and free living conditions. The majority of occurrences involved chimpanzees (Pan troglodytes) (n = 23) and mountain gorillas (Gorilla beringei beringei) (n = 8). This may reflect a larger amount of research with these species or possibly higher human to chimp and human to mountain gorilla contact.


One thing is for sure, these 33 events are just the tip of the iceberg since we know many disease events in great apes go undocumented and never reach the scientific literature. For example, I am personally aware of two zoonotic disease outbreaks: chickenpox from a keeper to gorillas in a zoo in the U.K. and polio in chimps at a zoo in the Republic of Congo. You will not find either of these events reported in the literature, but there is no doubt that both were caused by human to non-human great ape pathogen transmission. How many more stories like this are out there?


Six great ape species are endangered or critically endangered as determined by the International Union for the Conservation of Nature (IUCN). All six are experiencing decreasing population trends. (In fact, Homo sapiens [yes - us!] is the only species of the seven within the Hominidae family that is having population increases and is not endangered.) Our review shows that zoonotic pathogens transmitted from humans to our non-human Hominidae relatives may be a significant, but unappreciated, issue. We must work to better understand these zoonoses if we are to prevent human caused disease events from further threatening our closest living relatives.  

Work Cited

Dunay, E, Apakupakul, K, Leard, S, Palmer, JL, Deem, SL. 2018. Pathogen Transmission From Humans to Great Apes is a Growing Threat to Primate Conservation. EcoHealth. 1-15.

One Nation Under … Siege

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We are a nation under siege. Siege as “a prolonged period of misfortune” sums up the state of our Union today. We are indeed in a prolonged period of mass misfortune, which has only become worse since January 20, 2017, as the government chips away at health care access and women’s rights while sitting quietly on gun control. Refusing to begin a discussion on gun control is unfortunate on so many levels. 

Guns and Guitars

A shocking combination. (Image from )

A shocking combination. (Image from

You may think me naïve, but when the Guns and Guitars store front flashed onto my screen Monday following the Las Vegas massacre, I thought how odd that a store would sell guns and guitars. My confusion was mixed with the dread, horror and all but complete sense of hopelessness I felt in the face of the uncontrolled gun insanity that has crossed our land. Waking on October 2, 2017 to the news of the latest and greatest mass shooting in modern USA history did not feel unexpected. This news hit me in the same way as the news following the Columbine High School gun violence in 1999, Sandy Hook Elementary School killings in 2012, and the Pulse Nightclub slayings in 2016. Thoughts of sadness and rage and empathy all mixing together this week, just as they had following each of the countless other gun related murders in the US. The national heartache over the past week feels like déjà vu. Similar heartache to that which I felt after the shooting in 2007 at my Alma mater, Virginia Tech, even if the Va Tech violence felt a little more “personal”. All these gun tragedies were in one sense the same, while in so many other ways different; different for each of the victims and their families and friends. Similar in that they all may have been prevented if we could bring about common sense gun control.   

Living in the USA

I feel amazingly lucky to have been born in the USA and that I hold a United States of America passport. The places it has allowed me to travel and rights it has afforded me are a privilege. However, I am frankly shell shocked that so many of my fellow citizens cannot grasp the fact that we need change. This week I have been reading and re-reading the Amendments. They are mostly good, helpful and powerful for the people: this is especially true if considered in the context of what our country was like when the Bill of Rights came about.   

Of all the Amendments, the one that seems to have us stuck in a time warp is Amendment 2 - The Right to Bear Arms. Ratified in December 1791 this Amendment provides U.S. citizens the right to bear arms. The Amendment states, “A well-regulated Militia, being necessary to the security of a free state, the right of the people to keep and bear Arms, shall not be infringed.” Arms in 1791 might have looked something like this gun.  

Here is a Ketland Pistol. (Image from )

Here is a Ketland Pistol. (Image from

I am all for citizens of the US having rights and freedom. However, I question what we mean by freedom and rights. Do I have freedom from fear of being shot if I go into a school, stop next to someone at a traffic light, or enjoy myself at an outdoor concert? When does someone else's right impinge on my freedom? 

Bullets and Burgers  

For those seeking "The Ultimate Outdoor Machine Gun Experience" (Image from )

For those seeking "The Ultimate Outdoor Machine Gun Experience" (Image from

This week seeing Guns and Guitars reminded me of another commercial stop along the American road – Bullets and Burgers.  Famous for the incident in 2014 when a 9 year old girl accidentally killed her “instructor” at this restaurant/shooting range. This one gun mistake by a 9 year old ruined the instructor’s life and his family, as well as the girl’s life. 

I am happy for and appreciate my “inalienable rights” as a US citizen.  However, I have to believe that even the government officials who ratified the second Amendment in 1791 would see the world through different glasses—definitely through a different scope on their gun—today, and they too would realize it is time for change. 

This “gun thing” leaves me thinking of something Charles Darwin said a long time ago, “It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is most adaptable to change.”  America - it is time for change. 

Gun control = public health = One Health.

An Amazing Park and an Accident

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Three months ago today, I had an accident.  I would have rather of had a dream, but I had an accident.  Happily traveling along on my bike heading to work in Forest Park, St Louis, Missouri, I came to a standstill.  20 to 0 mph in a nanosecond.  The bike tumbled over 180 degrees, with my face the first body part to meet pavement.  The next 7 hours I spent drugged up in an ER getting ER type care.  Surgery days later to “fix” the shattered and lacerated nose and mouth.  In the intervening months, I have had lots of time to think about health across many scales: from the individual (me in this case!) to countries full of individuals; from humans to octopuses; and even from Earth to the Universe.   It also gave me plenty of time to contemplate why Forest Park and all urban parks matter. 

During these months, my thinking of health and parks was done out in the world, working on health projects in parks. First, I was at the Forest Park field site working with box turtles and snapping turtles and then in the Galapagos, studying giant tortoises (see for links to both these projects).   My doctor said, “You can heal in Missouri or you can heal in the Galapagos Islands.  Your choice.” (Yes, he is a very smart surgeon!)  Therefore, off to the Galapagos I went.  The past three months of contemplation of urban parks began within minutes of hitting the ground.  My first thought was ‘what the heck?’  The next thought was ‘where am I?’ It was this second thought to lead me on the path of pondering urban parks.         

No different to most accidents, I was within a mile of my house.  I was in a little known treasure in America, Forest Park in St. Louis, Missouri.  Forest Park is one of the largest, and dare I say best, urban parks in the USA at 1,293 acres with forests, fields, a Zoo (Best free attraction in America!), museums, golf courses, an outdoor theater or two, lakes, creeks and wildlife.  The wildlife in Forest Park alone is amazing.  There are birds, both resident and migratory, including the great horned owls of Mark the Owl Man fame (, amphibians, reptiles (all kinds of turtles), and mammals from the small to the not so small, with an occasional coyote or deer finding their way into the park.   Trust me when I say the best urban park in American claim is not something I take lightly as I grew up next to Rock Creek Park in DC and spent 5 years living near Central Park in NYC.  Forest Park is an urban gem surrounded by city. 

The park receives an estimated 13 million human visitors annually, which is not bad in a city of 316,000.  The Zoo alone gets roughly 3 million visitors a year.  At the Zoo, visitors may enjoy the natural world and learn to care for creatures with whom they share planet Earth, while improving their own health.  For example, zoo visits have been shown to improve human health both physiologically (lots of footsteps and lower blood pressure) and psychologically (increasing happiness and energy levels while decreasing tension).   If not a visit to the zoo, you may instead go to a museum for art, history or science, take a paddle boat out on the lake, walk the dog, take a stroll, smell a flower, or go bird watching.  The opportunities are endless, allowing one to reconnect to life and to, maybe just maybe, get a little healthier.  

That freaky accident on that beautiful May morning gave me the chance to spend time thinking about the value of urban parks, and the importance of these places for human, animal, and planetary health.  Urban parks help to minimize cities as heat sinks and areas of carbon dioxide build up.  A good thing for planetary health.  For animals, wildlife species increasingly rely on urban areas for survival, and parks may serve as safe havens for many species or stopover sites for migrating birds and other migrating animals.  As for humans, with more than 50% of us living in urban areas these oases of nature, in an increasingly urbanized world, may be what we need to remain sane and healthy in a world that often feels less than sane or healthy.  Parks might be just what the doctor ordered.  So get out into a park.  Remember though, if you are visiting on a bike, wear a helmet. 


Louv, R.  2011. The Nature Principle: Reconnecting with Nature in the Virtual Age.  Algonquin Books of Chapel Hill.  320 Pp.

Sakagami T., and Ohta M.  2010. The effect of visiting zoos on human health and quality of life. Animal Science Journal. 81: 129–134.

Sahrmann, J., Niedbalski, A., Bradshaw, L., Johnson, R.A., and Deem, S.L.  2016. Changes in Human Health Parameters Associated with a Touch Tank Experience at a Zoological Institution.  Zoo Biology. 35: 4-13.

Williams, F.  The Nature Fix: Why Nature Makes Us Happier, Healthier, and More Creative.  W.W. Norton & Company.  288 Pp.