Infected Elk May Pose Serious Health Risk to Humans

On February 12th, Washington Department of Fish and Wildlife (WDFW) officials concluded their most recent Hoof Disease Public Working Group Meeting with a sadly familiar message – they still did not know what was causing the crippling hoof disease that some have estimated is now responsible for half of all elk deaths in southwest Washington.

I was at the meeting as a hunter, a conservationist and a writer, and I was still bitter about my family’s bleak, unsuccessful hunting season that past fall. I was searching for answers and so far there weren’t any.

Before the meeting was adjourned, however, members of the public were allowed a chance to speak for three minutes each. First up was Boone Mora, a Doctor of Public Health from Skamokawa, Washington. Articulate and spry for his age, Dr. Mora stood and addressed the group.

Since I have so little time I’ll tell you I think I know what causes the disease. I think I know how to cure the disease, and I think I know how to prevent the disease. I spent ten years studying this disease. I was a guest researcher at the Center of Disease Control in Atlanta and I did a dissertation in this. I can tell you leptospirosis fits it better than anything else I can imagine. And leptospirosis hasn’t been investigated, certainly not exhausted. And I would like to do that. It won’t cost you anything. I’ll do it for nothing. The symptoms of this disease are as broad as symptoms go. This is why they are not diagnosed. People die from it.

And so began my plunge down the rabbit hole.

Dr. Boone Mora | Photo by Jon Gosch

To understand why leptospirosis is a possible cause of elk hoof disease, one must first discard the notion that the hooves are rotting. In newspaper articles and WDFW reports, elk hoof disease has been commonly referred to as hoof rot, but in fact it is the opposite. Pictures of infected elk clearly show that the majority of hooves are actually overgrown, often looking like deformed claws. Hooves that appear rotten are more likely the result of an overgrown hoof snapping off entirely.

Central to Dr. Mora’s diagnosis is the fact that one of the most common symptoms of leptospirosis is acute muscle pain. As scientist Linda Andersson writes in her study Leptospirosis: The Neglected Disease, muscle pain is most commonly located in the lower limbs and is so severe that even touching the muscle causes intense pain. According to Dr. Mora, this muscle pain in the legs, along with the flu-like symptoms of leptospirosis, may explain why scores of people have observed elk moving around less and lying down more often than usual. In one poignant example, a neighbor of Dr. Mora’s revealed that his children had discovered a group of wild elk near their home and were able to walk up and pet them.

This elk inactivity is an important point because if leptospirosis is capable of keeping an elk down or immobile for an extended period then it could account for the overgrowth of the hooves. Similar to our own fingernails, hooves are composed of keratin, and they will continue to grow unless trimmed by a farrier or else worn down by rocks, grit and game trails as is natural for a wild elk. If the hooves overgrow past a certain point, the elk may soon find itself doomed. Overgrown hooves can cause the elk to walk at angles which result in sprains and joint misalignment. These maladies then lead to inflammation, increased pain and further diminish mobility. The less the elk are running around, the more the hooves overgrow, and so on in what often becomes a torturous spiral into starvation and the most unfair and gruesome sort of predation.

There are other good reasons Dr. Mora believes his diagnosis fits. Leptospira bacteria are known to exist in the area and are particularly well-adapted to the moist climate of southwest Washington as they can survive for months in wet soil and fresh water. Often transmitted by animal urine or water containing animal urine, it is not hard to visualize how an entire herd of elk standing in a boggy field could quickly contract the bacteria. Leptospira are also spread through sexual intercourse, and although fluids are usually involved, the bacteria can even be transmitted by simply touching an infected animal.

WDFW’s own research shows that Leptospira bacteria have been widespread in the elk of southwest Washington. In 1996, Dr. Louis C. Bender, an employee of WDFW at the time, published a paper in the Journal of Wildlife Diseases entitled Leptospira interrogans Exposure in Free-ranging Elk in Washington. There is much to be learned from this study conducted on Centralia Mining Company property in Lewis County.

First and foremost, Dr. Bender’s field research showed that 14 of 17 sampled elk had been infected by Leptospira bacteria. According to Dr. Bender, “The high seroprevalence is evidence that exposure is widespread in the herd.” Dr. Bender did not mention whether or not any of the elk had overgrown hooves or appeared to be limping. He did, however, state that, “Previously we had tested [more than] 300 elk from throughout western Washington and found little or no exposure to [Leptospira] interrogans.” This last piece of information is striking because it suggests that the elk herd’s widespread exposure to Leptospira bacteria was a recent phenomenon.

Another striking component is Dr. Bender’s description of the immediate surrounding area as “hilly, heavily logged industrial forest.” Something seemed to have changed in the early 90s, and as many hunters and conservationists have noted, one of the biggest environmental changes at the time was the massive increase in herbicide use on industrial timber lands. Many herbicides are known to be immunotoxic, meaning they can drastically disrupt the function of an animal’s immune system. Atrazine, for instance, one of the most commonly used herbicides in southwest Washington, has been shown to decrease immune system strength by as much as 70%. It is still a speculative and controversial theory, but many wildlife activists now believe that weakened immune systems in the elk herds caused by excessive herbicide use may explain both how an epidemic of hoof disease got its start and why it originated when it did.

The following video shows how toxic herbicides like atrazine are typically sprayed by helicopter. On this occasion the spray was administered at a place known as the Gellatly Elk Reserve. Ironically, the Oregon timber company documented in the video goes by the name Starker Forests, Inc. No reports of elk hoof disease have so far been associated with Starker Forest’s herbicide regiments, but activists question why toxic chemicals are even being sprayed on an elk reserve at all.

If thousands of elk limping around our forests in excruciating pain isn’t enough to warrant studying Dr. Mora’s theory, then consider the following facts:

  1. Leptospirosis is contagious to humans and can be contracted by as little as touching the skin or hide of an infected animal.
  2. If left undiagnosed and untreated, leptospirosis and its complications often prove fatal to humans.

Leptospirosis is considered the world’s most common zoonosis, meaning it is a communicable disease passed between animals and man. In Linda Andersson’s study in the Andaman Islands, she documented that out of a population of less than 400,000, more than 50 people per year had died as a result of leptospirosis. On the surface this may not seem like an extraordinarily high percentage, but for somebody with frequent exposure to infected animals such as a hunter, a butcher or a veterinarian, the odds rise significantly. Andersson’s statistics also show that the cases of leptospirosis and related deaths initially grew over the course of her study because as the disease became better understood, it was discovered that more people had it.

Leptospirosis is also an elusive and routinely misdiagnosed disease that can’t be seen under a regular microscope and is often mistaken for other diseases like aseptic meningitis, hepatitis, influenza, pneumonia, brucellosis and food poisoning. The most common symptoms of leptospirosis include fever, chills, headache, nausea, vomiting and, of course, muscular pain. As Dr. Mora wrote in his 1978 dissertation devoted entirely to leptospirosis, “Of 318 cases in which initial impressions were recorded, only 17 percent were suspected of having leptospirosis.”

According to Dr. Mora, “Epidemics of leptospirosis in man and animals have occurred from Alaska to the tropics and all points between,” and they often wreak havoc for years or even decades before they are understood. In the 1940s, outbreaks of a fever at Fort Bragg, North Carolina remained undiagnosed as leptospirosis for eight years. In the Andaman Islands, it took fifteen years for Andaman hemorrhagic fever to be identified as leptospirosis. Just this past week, Dr. Katie Stephens, a veterinarian with the Cowlitz Animal Clinic in Longview, WA alerted pet owners that there had been five cases of suspected leptospirosis at the clinic in the past two weeks. According to Dr. Stephens, two of the dogs died acutely and one of the dogs was confirmed to have Leptospira autumnalis by the Washington State Animal Disease and Diagnostic Lab.

Since leptospirosis exhibits such a multitude of symptoms and manifestations, definitive diagnosis depends on laboratory results. It is most accurately diagnosed by isolating and identifying the organism, but this presents another challenge. There are more than 200 distinct variations (or serovars) of Leptospira bacteria, and many if not all of them could cause a lethal infection.

A WDFW report from June 2013 indicates the department had tested sixteen elk for six Leptospira serovars. Of these, four tested positive for L. icterohaemorrhagiae while the rest of the elk tested negative. It is these negative results that WDFW has so far used to discredit Dr. Mora’s diagnosis, and at first blush it seems hard to surmount.

According to Dr. Tom Besser, a Professor at Washington State University’s College of Veterinary Medicine, and a member of WDFW’s technical advisory group, “We have detected Leptospira in the kidneys of four animals, and that includes two animals that were infected and it also includes two animals that were not in the infected area at all. They were control animals.”

Besser continued, “We expect to see the possible cause more often in the animals that are affected than the animals that are not affected and that’s why the group has been so active at carefully selecting control animals from non-affected areas and testing them at the same time as the affected ones.”

Upon closer scrutiny, however, most of the technical advisory group’s arguments for dismissing leptospirosis quickly unravel. First, WDFW’s own hoof disease observations map plainly shows they have not been careful at all about which places they have designated as control areas. Their researchers have continuously referred to elk from Pacific and Grays Harbor Counties as unaffected when their maps show numerous, maybe dozens, of reports of limping elk throughout those counties. This massive elementary error alone is enough to question any of WDFW’s science regarding elk hoof disease. But there’s more.

To say that elk hoof disease cannot be caused by leptospirosis because some of the animals that have tested positive for leptospirosis don’t have elk hoof disease, as Dr. Besser and others have insinuated, is incorrect and poor science. Just as Magic Johnson has had HIV for two decades without developing AIDS, an elk can be a carrier and transmitter of Leptospira bacteria without developing hoof disease. Dr. Mora insists that when it comes to leptospirosis, positive test results are much more important and indicative of disease association than negative results are of the opposite. Serology tests also show that WDFW only tested for 6 of the more than 200 Leptospira serovars, and none of the 6 includes L. autumnalis which recently killed the two dogs in Cowlitz County.

Hoof Disease Observations Map | Washington Department of Fish and Wildlife

Throughout this investigation, activists have been continually perplexed by why WDFW officials are so resistant to accepting help from willing and capable sources. Dr. Mora, for instance, is the type of person all scientists should aspire to be. Brilliant, apolitical, and results-oriented, he is less interested in publishing esoteric academic papers than with solving problems and saving lives. After becoming a Doctor of Public Health, Mora would later go on to serve as a County Health Director for two counties in North Carolina, oversee research grants of up to $500,000, and win a Conservationist of the Year Award from the Soil and Water Conservation Society.

Considering his credentials, it is difficult to understand why WDFW officials have spent so much of their limited time and effort trying to disregard, discredit and disprove a man like Dr. Mora. For more than a year, Dr. Mora has generously offered his expertise and assistance in the lab and in the field at no additional cost to taxpayers. Far from being adequately researched, his leptospirosis theory has been deemed plausible by each of the several wildlife biologists I have spoken with outside of WDFW.

Instead of inviting him to make a full presentation to their advisory group, Dr. Sandra Jonker, a WDFW Wildlife Program Manager, notified Dr. Mora on Feb. 3rd, 2014 that he must apply for a Scientific Collection Permit. “You will note there is a fee ($117) associated with a Scientific Collection Permit application,” Jonker added in an email correspondence. It was not enough that Dr. Mora would do the work for free. He would need to pay $117 before his expertise would even be considered.

What is also maddening is trying to decipher why WDFW officials have continuously ignored the guidance of their own advisory group. After the last of the public comments at the Hoof Disease Meeting on Feb. 12th, Cowlitz County Commissioner James Misner made an appeal to WDFW officials.

“Can we hear some more from Dr. Mora if nobody else is speaking? I’d like to hear what he has to say. Can we give him another five minutes?”

Misner’s request was denied by WDFW Wildlife Program Director Nate Pamplin despite similar appeals from members of the advisory group and citizens in attendance. Visibly upset, Wahkiakum County Commissioner Dan Cothren vented his frustrations.

“I’m having a hard time with this. I think there are a lot of people in here that want to hear something. We have ten minutes. Now, I’m a Commissioner. I’ll allow that person that public time to speak and I don’t see why we can’t do that either. You shut him down like that and you’re shutting me down. Because what I see here is a meeting that’s going in the wrong direction.”

Resistance to help from Dr. Mora and other competent volunteers has extended all the way to the top of the organizational chart. On March 25th, a coalition of wildlife activists (including two members of the Hoof Disease Public Working Group) met with WDFW Director Phil Anderson and Governor Inslee’s Policy Advisor, JT Austin, in Olympia seeking permission to conduct private third party testing on elk in the affected areas.

Led by Mark Smith, owner of Eco Park Resort near Mount St. Helens, the coalition pointed out that WDFW has known about elk hoof disease for 18 years and has been actively investigating it for 5 years without any results. Smith stated that a third party study would take a more proactive role, its sole purpose to discover the cause and develop a treatment for elk hoof disease. Echoing a comment made by many activists, Smith pointed out that WDFW has been conducting clinical studies on dead animal samples to no effect, while the third party studies would focus on live animals. Smith’s coalition asked for no financial assistance from WDFW or the Governor’s office; only permission to help solve the mystery of elk hoof disease.

Smith said he received his answer a few days later. Request denied.

Lately, WDFW officials have been claiming they are close to determining that bacteria called treponema are the culprits behind elk hoof disease. “We have some pretty strong suggestions that treponeme bacteria are involved,” said WDFW spokesman Pat Miller. However, as recent newspaper articles have noted, WDFW’s treponema theory has many doubters.

Considering how frequently elk and domestic ungulates like cattle, sheep and goats occupy the same fields, and that whatever causes elk hoof disease seems to be contagious, many observers have wondered why the affliction has not crossed over to domestic animals. Corroborating the department’s treponema theory, WDFW epidemiologist Dr. Kristin Mansfield explained that, in fact, treponema has shown up recently in local domestic animals and helps account for its spread.

On the other hand, when I asked Dr. Paul Kohrs, the Acting State Veterinarian from the Washington State Department of Agriculture, about treponema in the domestic animals of southwest Washington he told me that his office knew of no recent incidents. Interestingly, Dr. Kohrs also told me that domestic cattle are usually vaccinated against leptospirosis. If Dr. Mora’s theory proves correct, this could help explain why there haven’t been any reported outbreaks of leptospirosis in the local domestic stock.

Most telling of all, Dr. Mora revealed to me only days ago that after more than a year and many dogged attempts to explain his leptospirosis theory in detail, he had finally been invited by WDFW to make a presentation to the technical advisory group. He didn’t know yet exactly when or where, but they had at long last reached out to him.

Dr. Boone Mora | Photo by Jon Gosch

Near the end of March I drove out to Skamokawa to meet with Dr. Mora at his home. He was going to have heart surgery in a couple days and he seemed to want to share as much information with me as he could. Just in case. We had just sat down at his dining room table to share notes when his telephone rang. It was the county engineer, relaying a report of an elk dead in Cathlamet with hoof disease. Within minutes we were in the car, chauffeured by his wife Jean. It would be the first deceased elk with hoof disease either of us had seen in person.

“This turned out to be a very fortuitous day for you to come down here,” Dr. Mora said.

The elk lay dead in a field at the outskirts of town. The neighbor who had called about the animal came out and told us the elk had been there a little over a day. He had originally called WDFW, but so far they had failed to arrive.

Dr. Mora and I approached the elk. It was an adult cow with very emaciated hindquarters. Its two back hooves were severely overgrown and deformed. One of the joints was extremely swollen. The front hooves also appeared overgrown, but nowhere near as misshapen as the rear. The cow’s hide was scratched and marred, probably from being unable to avoid low briars and brambles, but overall the elk did not appear to have suffered any major trauma. There was no evidence of a gunshot wound, predation or a car crash.

“It was easy to conclude that it was lying down because of its inability to negotiate,” Dr. Mora said later. “And so she fell and took time to starve to death.”

Later, Dr. Mora elaborated in detail how he would go about trying to cure elk hoof disease if he were finally given permission to conduct his own study.

After isolating live leptospires from tranquilized or freshly killed elk, Dr. Mora would like to prepare an oral vaccine that can be used in feed boxes in the wild. Because animals can shed leptospires in the urine for months, he would (in cooperation with a veterinarian) administer a long-lasting antibiotic to kill any viable leptospires and any bacteria causing secondary infection. In addition, the legs and joints would be treated with an anti-inflammatory like cortisone to reduce pain and encourage walking. Finally, a farrier could trim and repair hooves with something like Bovi Bond, and treated elk would be tagged and monitored.

As Dr. Mora well knows, what he is proposing is no small task. Significant resources and manpower (much of it volunteer) will be needed to execute his action plan. In addition he admits that, “I cannot imagine doing this project unless at the end we could truthfully say that we had the full cooperation of the Washington Department of Fish and Wildlife. We will need full authority to do research without interference and where possible we would be as inclusive as possible.”

Hunters and conservationists hope Dr. Mora will get the chance to investigate the enduring mystery that is elk hoof disease. At the moment it’s impossible to know if leptospirosis is the sole cause or whether herbicides are also involved, but the stakes are getting higher. The geographical scope of elk hoof disease is spreading and it will soon find its way into Washington’s three National Parks. And perhaps that’s exactly what it’s going to take for officials to marshal the adequate resources and political will – starving elk with deformed hooves limping into campgrounds at Mt. Rainier and the Olympics. Many more people will be wondering then how the state of Washington could allow one of its most iconic animals to suffer so horrendously for so long.

A Final Anecdote:

A week ago Dr. Mora implored me to read an article from the most recent issue of Science Magazine. The article was entitled Mesoamerica’s Mystery Killer and it documented a decade-long effort to understand a still mysterious affliction known as chronic kidney disease of unknown etiology (CKDu). Affecting agricultural workers throughout Central America, CKDu kills at least 2,500 people each year in El Salvador alone. Not once in the entire article did the author or any of the 12 quoted experts mention leptospirosis or the possibility that the disease could have been transmitted by contaminated water via infected animals.

After reading the article, Dr. Mora emailed one of the primary CKDu researchers, Dr. Peter Hotez from Baylor University, explaining that he believed leptospirosis to be the cause of the unknown disease and urging immediate action.

That same day Dr. Hotez replied, “Yes Dr Mora that’s the idea – we’re looking for a rodent borne infection, hantavirus or leptospirosis. I think that’s what it might turn out to be!”


To learn more about how toxic herbicides threaten our environment read: Growing Evidence Links Herbicides to Elk Hoof Disease

5 thoughts on “Infected Elk May Pose Serious Health Risk to Humans

  1. Amy Holler

    Have there been any deer affected?? If not why??? This theory sounds solid and plausible – but wouldn’t deer be affected if it is spread via contaminated water??

  2. ben

    Another thing that hasn’t been mentioned is where the deer, elk, and grouse primarily feed. I would venture to say that the biggest pastures are the sides of the roads. These areas are also sprayed most often I would venture to say. Just a little food for thought.

  3. Ron

    Can you imagine the huge loss of revenue for the WDFW if this were discovered? That is probably not why they aren’t looking into this.


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