Defeating the Resistance of Staph Infections Among Canines

Can the same drug-resistant illness that has been killing people in record numbers infect your dog? Can drug-resistant Staph infections be passed between dogs and humans? Is your dog at risk? Might your dog be a health hazard to others?

The answers are yes, yes, and maybe. Fortunately, there are many ways to prevent the spread of bacterial infections, including the drug-resistant kind.

Understanding MRSA
For decades, public health officials warned that the overuse of prescription antibiotics and antibacterial soap and hand wipes could lead to the growth of “supergerms,” drug-resistant bacteria that are difficult if not impossible to control.

They were right. In fact, just four years after penicillin became available in 1943, scientists documented microbes that could resist it. The first was Staphylococcus aureus, a ubiquitous bacterium that is usually harmless but which in susceptible patients can cause pneumonia, severe skin infections, or toxic shock syndrome.

By the 1990s, one strain became especially problematic. MRSA (pronounced MER-sa), or Methicillin-Resistant Staphylococcus aureus, got its name because the drug most commonly used to control it no longer worked.

Since then, MRSA outbreaks have been increasing in the United States, England, and other countries. In the U.S., infection rates tripled between 2000 and 2005. According to the Journal of the American Medical Association, an estimated 95,000 Americans contracted MRSA in 2005, resulting in 18,650 deaths, a number that surpassed that year’s HIV/AIDS death rate. In most cases, patients who died were elderly, already ill, or at risk because of compromised immunity, but MRSA has also killed the young and healthy, including, last October, teenagers in Virginia and New York.

Staph bacteria live on the skin or in the nose of about one-third of the world’s population. Those who harbor the bacteria but don’t have symptoms are “colonized” but not infected. They are carriers of the illness and can infect others.

Fortunately, Staph bacteria are usually harmless because the immune systems of most dogs and humans successfully keep the bacteria in check. Even if they enter the body, they cause only minor skin problems in most cases. In susceptible individuals, however, the bacterial population can suddenly increase and sicken its host.

Physicians check for MRSA by sending tissue samples or nasal secretions to diagnostic laboratories. Because bacterial culture tests take 48 hours and time is of the essence, tests that quickly detect Staph DNA are becoming widespread.

There are two types of MRSA: Hospital-Acquired (HA) and Community-Associated (CA).

HA-MRSA is alive and well in healthcare facilities, its original breeding ground. This strain, which is highly resistant to treatment with conventional drugs, causes internal infections in vulnerable patients, usually after gaining access to the body through catheters, surgical wounds, feeding tubes, invasive medical procedures, or lung infections. Those most at risk are the elderly, ill, and immune-compromised.

CA-MRSA is less resistant to treatment but more dangerous because it grows rapidly in otherwise healthy patients. Its initial symptom looks like a red pimple, boil, insect bite, or spider bite. If left untreated, the swelling develops into abscesses that cause fever, pus, swelling, and pain.

Those most at risk of acquiring CA-MRSA include children, people of all ages who have weakened immune systems, those who live in crowded or unsanitary conditions, people who are in close contact with healthcare workers, and professional and amateur athletes who participate in contact sports. Sharing towels, razors, uniforms, and athletic equipment has spread MRSA among sports teams.

Dogs at risk
There have been many disturbing reports about MRSA, but the most alarming to dog lovers is the news that humans can infect dogs with this disease and vice-versa.

Michelle Rivera, who lives in North Palm Beach, Florida, contracted MRSA in 2005, the same year that 64 residents of Palm Beach County died of the disease. “I never once heard that my pets could be at risk because of my infection,” she says. “I was in a drug-induced coma for three weeks and bedridden for six months. This is one nasty superbug.”

Last October, the New York newspaper Newsday reported that MRSA cases are increasing among pets and that many pets have contracted the disease from their owners. Newsday quoted Patrick McDonough, PhD, an assistant professor at Cornell University’s veterinary college: “This is what we call reverse zoonosis. The organism is moving from people to animals. Once animals colonize it, we don’t know how long they maintain it, but this is one case where they are sharing what we have.”

In the same article, veterinarian Lewis Gelfand, DVM, of Long Beach, New York, reported that he has seen 19 cases of MRSA in dogs during the past year. “I believe it is a significantly underdiagnosed and rapidly expanding problem,” he said. “We have been seeing dermatological cases as well as open sores.”

On November 9, 2007, Fox News Channel 40 in Binghamton, New York, reported that Cooper, a 100-pound Italian Spinoni belonging to Andrea Irwin, had been diagnosed with MRSA, which caused sores all over the dog’s stomach and legs.

“He had recurrent Staph infections since the fall of 2004,” Irwin told reporters. “He had been treated on and off for those infections, but they never cleared up totally. This July the vet decided it was time to take some skin cultures and send them to Cornell University, where Cooper tested positive for the human strain of MRSA.” Following successful treatment, he made a full recovery.

When Cooper was diagnosed, Irwin felt frustrated by the lack of information available about MRSA’s effect on dogs. “The only information I could find was from a website for the Bella Moss Foundation,” she said.

English actress Jill Moss created the foundation in memory of her Samoyed, Bella, who ruptured a cruciate ligament in July 2004 while chasing squirrels in a London park. What should have been a routine repair turned into a nightmare when Bella’s leg swelled with pus. Because the veterinarians who treated her didn’t recognize MRSA, Bella became the world’s first documented canine fatality from the disease. Pets-MRSA.com, the foundation’s website, is a leading information resource about MRSA’s effects on animals.

Preventing MRSA
Public health officials agree that the best way to prevent MRSA is with frequent hand washing. Scrub hands briskly with soapy water for at least 15 seconds before rinsing, then dry them with a paper towel and use a second paper towel to turn off the faucet and open the bathroom door.

When you don’t have soap and water, use a hand sanitizer that contains at least 62 percent alcohol or a small amount of disinfecting essential oils. The chemicals used in antibacterial soaps and hand wipes have been blamed by public health officials for the mutation of drug-resistant bacteria, so consider alternatives to soaps and wipes containing antibacterial chemicals.

Clean and disinfect all cuts, wounds, bites, stings, and open sores. Keep wounds clean and covered with sterile, dry bandages until they heal. Sanitize linens if you or your dog have any cut or sore by washing sheets, towels, and bedding in hot water and drying them in a hot dryer.

If you or your dog have a persistent skin infection, have it tested for MRSA to be sure you receive an antibiotic that is targeted to wipe out the bacteria, without promoting the resistant population.

Last, use antibiotics appropriately. Follow label instructions and don’t share or save unfinished antibiotics. Because antibiotics are not effective against viruses, don’t insist on getting a prescription for a cold or other viral infection.

Holistic care and prevention
Keeping colonized dogs from spreading MRSA and keeping at-risk dogs safe requires frequent hand washing, dog bathing, and keeping wounds and bedding clean.

Dogs that are MRSA carriers or who have close contact with someone infected with MRSA can pose a risk to small children, pregnant women, the elderly, and anyone with an active illness or open sore. Commonsense precautions include keeping your dog clean and not letting your dog lick everyone.

Probiotic supplements are recommended for MRSA prevention because beneficial bacteria are the immune system’s first line of defense. Products containing Lactobacillus bacteria, especially L. sporogenes, or other beneficial bacteria can be given before meals or according to label directions.

According to Mary G. Enig, PhD, one of the world’s leading experts on fats and oils, coconut oil’s medium-chain fatty acids inhibit the growth of many pathogenic microorganisms, including Staph bacteria. She sites research on two strains of S. aureus showing that monolaurin from coconut oil combined with the essential oil of oregano, which is itself a powerful disinfectant, worked better than the most potent antibiotic.

“This research showed,” she writes, “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 of coconut oil for dogs is 1 teaspoon per 10 pounds of body weight per day, or up to twice that amount in divided doses if the dog is a carrier, has an active infection, or is exposed to someone with MRSA. Start with small amounts and increase gradually. (See “Crazy About Coconut Oil,” Whole Dog Journal October 2005.)

Many essential oils kill harmful bacteria, including cinnamon bark, clove bud, savory, thyme, lavender, tea tree, and the previously mentioned oregano.

Oregano essential oil (be sure the label says Origanum vulgaris, preferably wildcrafted or organic) can be given to dogs internally 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! 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 10-15 pounds.

Cinnamon bark oil is a powerful skin irritant and should not be applied externally, but it can be added to laundry water to disinfect towels or bedding. All of the essential oils mentioned here, including cinnamon, can be dispersed in an aromatherapy diffuser or mixed with water (20 drops per quart or 5 drops per cup) and sprayed in the air, avoiding furniture and pets, or on kitchen and bathroom surfaces, doorknobs, crates, and pet bedding.

Manuka honey, mentioned in “Bee Products” (September 2007), is a proven Staph killer. A teaspoon to a tablespoon of honey, fed to a dog twice a day, can help him fend off harmful bacteria. Colloidal silver is another disinfectant that has been proven to kill S. aureus. It can be applied externally to cuts and wounds, sprayed directly on a dog’s coat (including the face, nose, and groin areas, where Staph bacteria tend to colonize), and taken internally.

For best results, use a product like Sovereign Silver, which contains very small silver particles in a base of pure water. For maintenance, give ¼ teaspoon per 20 pounds of body weight between meals every other day. If your dog is exposed to MRSA or any other contagious illness, give the same dose three times per day. Larger doses (consult the manufacturer) can be used to treat active infection.

One of the easiest ways to keep your dog 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, even fleas and unattached ticks. Microfiber fabric does not disinfect, but it picks up and removes bacteria. The cloths can be washed in hot water (add a few drops of cinnamon or tea tree oil or a blend of disinfecting essential oils) and dried in a hot dryer to kill microorganisms. Don’t use fabric softeners and dryer sheets when laundering microfiber cleaning cloths.

MRSA may be a frightening illness, but by following the simple prevention steps described here, you can help ensure that you and your dog enjoy an active, happy, MRSA-free life.

CJ Puotinen, a frequent contributor to WDJ, is co-director of the Hudson Valley Humane Society Visiting Pet Program in Rockland County, New York, and its annual Therapy Dog Camp. The organization’s members include therapy dogs and other animals. See HudsonValleyVisitingPets.com for more information.