Are Raw-Fed Dogs a Risk?

Delta Society is one of the largest and best-known organizations that registers and insures “pet therapy” volunteers and their companion animals. Pet/handler teams – known as Pet Partners – brighten lives in hospitals, nursing homes, group homes, schools, pre-kindergarten programs, libraries, jails, women’s shelters, homeless shelters, senior centers, adult day programs, and a host of other facilities.

But on May 19, Delta Society triggered a firestorm of controversy, complete with conspiracy theories, angry denunciations, frustration, and confusion, when it announced that effective June 30, “any dog or cat from a household where raw protein food is fed is not eligible to be a Delta Society Pet Partner.”

Delta’s Raw Protein Diet Policy raises serious questions about the safety of feeding raw food regardless of an animal’s pet-therapy status. Are raw-protein diets truly dangerous for dogs and the people who touch them? We think not. Should responsible owners reconsider their feeding plans? We say no. Here’s why.

Delta suggests that even a dog or cat who eats a conventional commercial diet and shares a household with a raw-fed dog or cat may be ineligible to be a Pet Partner. “If a Pet Partner has access to the food or bowl used, it would be best to NOT feed any of the other pets raw meats. Inadvertent eating of raw meat or cross-contamination is very real.”

Delta’s board of directors believes that raw-fed animals pose a serious risk of infecting clients with zoonotic pathogens.  Its new policy statement concerning raw-fed Pet Partners asserts, “It is well known that animals fed raw diets (BARF or other) shed significant amounts of pathogenic bacteria, which studies have indicated may put some people at risk, as compared to pets being fed commercially prepared or cooked, home-made diets . . .

“Even healthy animals can shed pathogenic bacteria that can affect the human companion team member and others. Certain individuals are at increased risk of disease if they encounter various pathogens, particularly people that are immune-compromised, very young, or elderly. This basically describes most of the individuals Delta Society Pet Partners visit: Patients in hospitals, senior centers, nursing facilities, hospice care, rehabilitation facilities, and schools involving young children, among others.”

Delta acknowledges that dogs fed commercial or home-cooked diets can shed pathogenic bacteria, but believes these dogs pose a lower risk of bacterial shedding. Delta Society volunteers who feed commercial pet food or a home-cooked diet are unaffected by the organization’s new policy – but those who feed their animal companions raw protein must either change those diets or leave their Delta Society-sponsored volunteer work. If a Pet Partner does switch to a cooked or commerical diet, Delta suggests suspending therapeutic visits for a minimum of four weeks, because dogs can shed pathogenic bacteria for a variable amount of time.

The new policy
Delta’s policy change caught its many raw-feeding volunteers by surprise. How did Delta Society decide that raw-fed animals pose a health risk to the clients served by its program?

 On its website, Delta Society explains the rationale for its policy change: “Over the past few years, the increasing use of raw protein diets and the health concerns and controversy generated have grown, not only between the public and veterinarians, but often within the veterinary profession itself. After careful consideration of all of the known scientific facts, and on the unanimous advice of the Delta Society Medical Advisory Board, made up of internal medicine and public health experts from North America, the board of directors voted to preclude animals eating raw protein foods from participating in Delta Society Pet Partners program.”

Some raw feeders see an ominous connection between the development of the policy and the fact that Delta Society receives financial support from Purina. One of its Medical Advisory Group members, Deborah S. Greco, DVM, PhD, DACVIM, works for Nestle Purina Petcare in St. Louis, Missouri. Delta acknowledges Purina on its website, displaying the Purina logo under the statement, “Thank you to our incredible partner, the passionate pet lovers at Purina!”

Apparently anticipating that some would blame Delta’s link to Purina as the cause of its ban on raw-fed animal partners, Delta clarified:

What was the role of pet food manufacturers in the adoption of the Raw Protein Diet Policy?
  No pet food manufacturer representatives contacted, encouraged, lobbied, or influenced the Delta Society Medical Advisory Group in recommending to the board that they approve a Raw Protein Diet Policy.
. . . As board members learned of medical professionals’ concerns about the increased risk of the spread of pathogenic bacteria to humans by animals fed raw protein diets, it was determined that this was an issue that needed review. . . . As many of our Pet Partners visit in hospitals, assisted-living centers, and other places where people’s immune systems are compromised, it was decided that implementing this new policy was the responsible action.

A look at the pathogens
Delta Society’s Raw Protein Diet Policy explains, “Since many studies have shown pets fed such diets shed a significantly higher number of pathogenic bacteria, the risk is too great for inadvertent, but avoidable infection.” Here’s a look at the bacteria of concern.

According to the Centers for Disease Control (CDC) in Atlanta, Georgia, foodborne diseases cause approximately 76 million illnesses, 325,000 hospitalizations, and 5,000 deaths in the U.S. each year.

Salmonella, which causes nausea, vomiting, diarrhea, abdominal pain, fever, chills, headache, and blood in the stools, is the most common bacterial cause of foodborne outbreaks.

About half of all Salmonella infections occur in restaurant settings. According to the CDC, 1.4 million Americans contract Salmonella each year, but because mild cases are often dismissed as “stomach flu” and go unreported, the U.S. Food and Drug Administration (FDA) estimates that the annual number is more likely 2 to 4 million. About 1,000 people in the U.S. die of Salmonella infections each year.

In a series of articles published in 2008 about Salmonella outbreaks, the Journal of Food Protection reported that infections traced to specific restaurants are often linked to carriers (people who are infected but not symptomatic) who prepare food. No one knows how many Americans are asymptomatic carriers at any given time, but the number discovered by fecal testing is significant.

“Contamination most frequently occurs via the fecal-oral route when pathogens are present in the feces of ill, convalescent, or otherwise colonized persons,” says report author E.C. Todd. “It is difficult for managers of food operations to identify food workers who may be excreting pathogens, even when these workers report their illnesses, because workers can shed pathogens during the prodrome phase of illness or can be long-term excretors or asymptomatic carriers. Some convalescing individuals excreted Salmonella for 102 days. . . Regardless of the origin of the contamination, pathogens are most likely to be transmitted through the hands touching a variety of surfaces, highlighting the need for effective hand hygiene and the use of barriers [such as plastic gloves] throughout the work shift.”

Salmonella can contaminate meat, poultry, eggs, and milk, but it can also occur in fruits and vegetables, especially those that grow close to the ground or fall from trees to the ground (like nuts). Contaminated food manufacturing plants can spread the bacteria to all types of processed foods. Major Salmonella-related food recalls during the past six years involved almonds, Hershey and Cadbury chocolate bars, serrano peppers from Mexico, pistachio nuts, peanuts, peanut butter, Italian salami, and numerous products containing hydrolized vegetable protein (a flavor enhancer).

Some pets are notorious carriers of Salmonella, especially snakes, turtles, and other reptiles.

Salmonella-contaminated pet food has also sickened humans who handled the food. In 2006, 79 human cases of Salmonella in 21 states, most involving very young children, were traced to a Mars Petcare plant in Pennsylvania. Mars recalled 23,109 tons of Salmonella-contaminated dry dog and cat food, sold under 105 brand names. Other recent pet food recalls involved Salmonella in pig ears, cow hooves, beef treats, and dog treats made with peanut butter.

In 2008, when eight additional human cases of Salmonella were traced to dry pet foods, Dr. Pascal James Imperato, dean and distinguished service professor of the graduate program in public health at State University of New York Downstate Medical Center in Brooklyn, told reporters, “There is greater industrialization of the production of food products, both for humans and animals, and these are complex processing systems. Therefore, there is greater opportunity for contamination. We are likely to see many more of these problems in the future.”

To help prevent infection, Dr. Imperato recommends regular washing of pet food bowls to prevent bacterial growth; the thorough washing of hands with soap and warm water for at least 20 seconds after handling dry pet foods, including pet treats; and scrupulously avoiding contact between dry pet foods and foods consumed by humans as well as food preparation surfaces and utensils. Keep infants away from pet feeding areas and prevent children younger than age five from touching or eating pet foods, treats, or supplements.

Escherichia coli (E. coli) bacteria cause severe cramps and are a leading cause of bloody diarrhea. Most E. coli infections come from ingesting contaminated meat, water, or dairy products, or working with cattle, but dangerous strains of E. coli can be present in fruits, vegetables, nuts, and processed foods. In 2006, E. coli in packaged fresh spinach killed three people and hospitalized more than 100. More recently, Consumers Union (publisher of Consumer Reports) announced that nearly half of the water and soda dispensers it tested at fast-food restaurants and 39 percent of the pre-washed, packaged salad greens it examined contained “unacceptable levels” of coliform (fecal) bacteria, which were likely to include both Salmonella and E. coli.
Clostridium difficile, often called C. difficile or “C. diff,” causes watery diarrhea, fever, loss of appetite, nausea, and abdominal pain or tenderness. Severe cases produce life-threatening inflammation of the colon. This bacterial infection commonly affects older adults in health care facilities and typically occurs after the use of antibiotics. In recent years, its infections have become more frequent, more severe, and more difficult to treat, making C. difficile a bane of hospitals and nursing homes.

Staphylococcus aureus, a common bacterium found on the skin and in the nasal cavities of up to 30 percent of healthy people and animals, can produce toxins that cause gastrointestinal food poisoning. Sliced meat, puddings, pastries, sandwiches, and other foods have caused Staphylococcal food poisoning. The most famous member of this bacterial family, methicillin-resistant Staphylococcus aureus (MRSA, pronounced MER-sa), is not considered a foodborne pathogen. This life-threatening “supergerm” is usually acquired in a hospital setting, though “community-acquired” MRSA is the more dangerous strain. (See “Defeating the Resistance,” WDJ January 2008.)
 
Bacterial shedding
According to the University of Wisconsin’s School of Veterinary Medicine’s website, “Salmonella spp. can be isolated from healthy dogs and cats at rates of up to 36 and 18 percent, respectively. Dogs and especially cats can shed Salmonella organisms in both their feces and saliva, meaning that transmission can occur via licking. Dogs and cats may suffer salmonellosis as a ‘reverse zoonosis,’ with infection transmitted from human-to-dog and subsequently back to other humans. Similarly, outbreaks of Salmonella infections in large animal teaching hospitals have been linked to the introduction of bacteria from infected human personnel, with subsequent spread to animals and then back to other human workers.”
Although dogs can contract salmonellosis, healthy dogs usually remain free from symptoms of infection even when they ingest Salmonella bacteria.

In a study reported in the Canadian Veterinary Journal in 2007, 7 of 16 research dogs given Salmonella-contaminated raw food shed salmonellae in their feces the following week. The remaining nine did not shed salmonellae, and none of the dogs exposed to the bacteria exhibited any symptoms of illness. Although the study’s size was very small, it suggests that most healthy dogs effectively neutralize Salmonella without colonizing or shedding the bacteria.

Delta Society Medical Advisory Board member J. Scott Weese, DVM, DVSc, DACVIM, of the Ontario Veterinary College at the University of Guelph in Canada, has co-authored several studies of zoonotic agents in Ontario-area dogs.

A 2006 cross-sectional study of 102 healthy visitation dogs tested their stool samples, hair brushings, and rectal, aural, nasal, oral, and pharyngeal swabs for 18 specific pathogens. Zoonotic agents were isolated from 80 of the dogs (80 percent), the primary agent being Clostridium difficile, which was present in 58 percent of the tested dogs.

Two studies published in 2009 tested therapy dogs for MRSA and C. difficile. In one, both MRSA and C. difficile may have been transferred to the fur and paws of canine visitors through patients handling and kissing the dogs, or through exposure to a contaminated healthcare environment. In the other, the rates of acquisition of MRSA and C. difficle were 4.7 and 2.4 times as high, respectively, among dogs who visited human healthcare facilities compared with rates among dogs involved in other animal-assisted interventions. Among dogs who visited human healthcare facilities, those who licked patients or accepted treats during visits were more likely to be positive for MRSA and C. difficile than were dogs who did not lick patients or accept treats.

Another study, co-authored by Dr. Weese and published in 2008, examined stool samples collected every two months for one year from 40 raw-fed therapy dogs and 156 therapy dogs who were not fed raw food. The study showed these positive test results:

■ Vanomycin-resistant enterococci: 0 raw-fed dogs (0 percent) and 1 cooked-food dog (0.6 percent)

■ MRSA: 1 raw-fed dog (2.5 percent) and 8 cooked-food dogs (5.1 percent)

■ Clostridium difficile: 5 raw-fed dogs (12.5 percent) and 40 cooked-food dogs (25.6 percent)

■ Salmonella: 19 raw-fed dogs (47.5 percent) and 12 cooked-food dogs (7.7 percent)

■ E. coli: 31 raw-fed dogs (77.5 percent) and 32 cooked-food dogs (20.1 percent)

Are these statistics significant? The studies’ samples are small and regional. They don’t differentiate between dogs fed ingredients from factory-farmed and pasture-fed animals (pasture-fed meat, poultry, and eggs have been shown to have significantly lower Salmonella and E. coli bacteria counts than the same ingredients from animals raised in confinement).
Neither do the studies consider infection control measures that are easily implemented in animal-assisted therapy programs or by therapy dog handlers at home. And rather than proving that raw-fed dogs are dangerous, the studies suggest that all dogs, regardless of diet, may be agents of infection.

Many dog lovers counter with questions about human visitors to health care facilities. Have they been screened for bacteria? Might their clothing or handshakes and kisses spread pathogens in all directions?

Another variable to consider is the human immune system. While it certainly makes sense to reduce the exposure of medically fragile patients to potentially harmful bacteria, the germ theory of disease does not explain every illness, and not all immune-compromised patients who are exposed to pathogens become infected.

In fact, some studies, such as “Effect of Petting a Dog on Immune System Function” by C. Charnetski, et al, in the medical journal Psychological Reports (December 2004), show that petting a dog boosts immunity. For more than 30 years, Delta Society has documented the health benefits of pet visits, and its website and published reports provide a wealth of information on this subject.

Legal liability
Until it announced its new policy, Delta Society deferred to its members’ veterinarians regarding diet, vaccinations, parasite control, and other health matters. The new policy links its decision to override the dietary recommendations of its Pet Partners’ veterinarians to the organization’s legal responsibility for the animals it insures.

But according to attorney Ray Mundy of New Hempstead, New York, who has served as president of the Hudson Valley Humane Society for more than 15 years and is well acquainted with lawsuits involving animals, the likelihood of anyone suing an organization like Delta Society for infecting someone with Salmonella, E. coli, or any other pathogen is negligible – and the likelihood of such a suit succeeding is, he says, “beyond imagination.”

While it’s true that in the United States, anyone can sue anyone about anything, contingency fees are the standard in personal injury cases. In contingency cases, attorneys who file a lawsuit aren’t paid until and unless the case is decided in the plaintiff’s favor.

“This system filters out frivolous suits,” says Mundy, “along with cases that aren’t likely to succeed. For someone to sue a therapy dog organization for infecting a client or patient, they would have to prove that the infectious agent, whatever it was, came directly from the animal and nowhere else. Considering how ubiquitous infectious pathogens have become in our society, how many facilities allow visits from unscreened dogs belonging to friends or family members, and how many human visitors carry bacteria on their hands and clothes, that burden of proof is for all practical purposes impossible.”

This is especially so, he says, when pet handlers with special training visit with screened, healthy, clean animals, and when handlers and facility staff encourage clients to wash their hands or use a hand sanitizer after petting therapy animals.

Other strategies that help reduce infection when visiting at-risk patients include preventing therapy dogs from licking the people they visit; using barrier protection, such as placing an extra sheet on the bed and another on the patient before a visiting dog sits or lies next to the patient; working with a staff or volunteer escort who can watch for hazards and assist clients or patients with hand cleaning; and not visiting patients with open wounds or those who are in isolation for infection control.

Infection control options
According to Mary G. Enig, PhD, an expert on fats and oils, coconut oil’s medium-chain fatty acids inhibit the growth of many pathogenic microorganisms, including Staph bacteria. Coconut oil’s capryllic acid significantly reduces Salmonella and Campylobacter jejuni (another serious foodbourne pathogen) when fed to chickens and other animals. Dr. Enig cites research on two strains of S. aureus showing that monolaurin from coconut oil combined with the essential oil of oregano (itself a powerful disinfectant), worked better than the most potent antibiotic.

She writes, “This research showed that these safe antimicrobial agents could be useful for prevention and therapy of Staphylococcus aureus and numerous other infections. It is now clear and scientifically validated that the inclusion of coconut oil in the diet could and should be utilized for its preventive and healing properties.”

The recommended amount for dogs is 1 teaspoon per 10 pounds of body weight per day. Start with small amounts and increase gradually. (See “Crazy about Coconut Oil,” WDJ October 2005, for more information about coconut oil’s benefits to dogs.)

Oregano essential oil can be given to dogs by placing drops in an empty two-part gel cap (available at health food stores), closing the cap, and placing it in a small amount of food so that the dog swallows it whole. Dogs do not like the taste! When buying, be sure the label says Origanum vulgaris, preferably wildcrafted or organic. Use 1 drop of oregano oil per 50 pounds body weight once or twice per day. For small dogs, dilute 1 drop essential oil in ½ teaspoon vegetable oil and give ⅛ teaspoon per 10 to 15 pounds of the dog’s body weight.

Clorox bleach effectively kills Salmonella, E. coli, MRSA, and other harmful bacteria. Meat, poultry, fish, and eggs can be disinfected by soaking them in a solution of 1 teaspoon regular unscented Clorox in 1 gallon of water. Soak eggs for 20 to 30 minutes; soak meat, poultry, or fish for 10 minutes per pound if fresh and 15 to 20 minutes per pound if frozen. Immediately place food in a fresh water rinse for 10 minutes.

To disinfect counters and work surfaces, add 1 tablespoon Clorox to a gallon of water. Spray or wipe and let air dry. To disinfect sponges and dish cloths, prewash, then soak in ¾ cup Clorox diluted in 1 gallon water for 5 minutes; rinse, and dry.

Alternatively, portable steam cleaners have become popular becuse they’re easy to use and effective sanitizers of kitchen counters, sinks, floors, pet bedding, and other surfaces.

Your microwave is a powerful germ killer, too. A study published in 2007 in the Journal of Environmental Health showed that zapping wet sponges, plastic scrubbing pads, and dishcloths in the microwave for two minutes at full power killed or inactivated more than 99 percent of the living germs and bacterial spores that contaminated them, including E. coli.

One of the easiest ways to help keep dogs clean is with microfiber cleaning cloths. These rough-textured polyester-polyamide cloths were originally developed for “clean room” applications in the semi-conductor industry. Used wet or dry, they attract and trap dust, dander, loose hair, and other particles. Microfiber fabric does not disinfect, but it picks up and removes bacteria. Dogs can be wiped with clean microfiber cloths during therapy visits to minimize the transfer of potentially harmful bacteria from hands that pet them. The cloths can be microwaved or washed in hot water with bleach and dried in a hot dryer. Don’t use fabric softeners or dryer sheets, which reduce the cloths’ effectiveness.

In addition, several brands of disinfecting pet wipes or sprays can be applied to a dog’s coat or paws.

The future of pet visits
Delta Society’s abrupt announcement of its new policy has sent shock waves through both raw-feeding and pet-therapy communities. Many advocates of raw feeding as well as concerned Delta Pet Partners have sent letters and emails asking the organization to reconsider.

The American Humane Association’s (AHA) Animal-Assisted Therapy program, headquartered in Englewood, Colorado, is one of the largest Delta affiliates in the nation. AHA President and CEO George C. Casey and Senior Vice-president of Human-Animal Interactions Marie McCabe, DVM, wrote in a June 2 letter to Delta Society, “We invite Delta Society to share additional details [that led to the new policy] and consider an inclusive process of both reviewing the science behind the decision and revisiting the decision itself. The new policy has a tremendous impact, not only on Delta Society volunteers, but on all the clients they serve. Additional background and facts regarding the basis for this sudden and drastic decision would allow our staff and volunteers to evaluate it for themselves. Without such information, we are concerned that many members, and even affiliates, may elect to withdraw from the Delta Society Pet Partners program.” The AHA’s questions to Delta Society include:

■ What prompted this decision and short compliance deadline which provides virtually no opportunity to phase in changes in therapy-animal diets?

■ Has there been a recent incident involving one or more persons contracting Salmonella or E. coli from a therapy animal on a raw protein diet?
 
■ Have the Centers for Disease Control and the Joint Commission (an accrediting agency of health-care organizations) been consulted and, if so, do they concur with Delta Society’s position?

■ Has Delta Society determined the number of therapy animals and clients potentially be impacted by the decision?

Delta Society has invited members to submit questions about the new policy to its Medical Advisory Group, which will answer them through a FAQ page at the Delta website. We submitted the following questions:

■ How does Delta Society plan to enforce its new policy?

■ Can dogs continue as Pet Partners if they eat raw cheese sold for human consumption (a protein food) as a snack, training treat, or as part of their dinner?

■ Does the restriction apply to freeze-dried raw treats or foods, such as Wysong’s, or a dehydrated raw diet, such as Honest Kitchen?

■ Are dogs who are fed a commercial diet but occasionally eat cat droppings, manure, or dead animals prevented from making visits as part of this new policy?

■ What about commercially fed dogs with coprophagia?

■ What about commercially fed dogs who live in messy houses? Or with reptiles? Or with people who are themselves spreading Salmonella or other infections?

As this article goes to press, no members’ questions or answers have been posted at the Delta website, nor has the organization announced any change or review of the new policy.

Considering the many documented social and health benefits of pet visits – animals have a calming effect on people; petting a dog lowers blood pressure and calms heart rates; pet visits boost morale and provide important social stimulation and interesting activities; pet visits encourage cooperation among clients or patients as well as cooperation with health care practitioners; and contact with pets can significantly improve quality of life – it’s no wonder therapy dogs are popular.
Some Delta-affiliated groups with raw-feeding members plan to continue as independent organizations with their own liability insurance. Others may turn to regional organizations or to Therapy Dogs Incorporated, Therapy Dogs International, the Foundation for Pet Provided Therapy (Love on a Leash), or Paws for Friendship, Inc., all of which are national/international therapy dog registries and none of which ban the participation of animals fed raw protein.

As researchers Sarah Brodie, Francis Biley, and Michael Shewring concluded in their 2002 report “Exploration of the potential risks associated with using pet therapy in healthcare settings” in the Journal of Clinical Nursing, “A search of the literature has assessed potential and actual risk and concludes that the hazards are minimal. The potential to suffer harm does exist but it can be minimized by taking simple measures, including careful selection of animal and client, thorough planning and allocation of responsibility, rigorous health care of the animal, and informed practices by all involved.”
 
CJ Puotinen was, until June 30, a Delta Society Pet Partners training instructor, and, with her Labrador Retriever, a Delta Pet Partner. She is also a prolific author of books on holistic health.