Animals can carry and transmit strains of methicillin-resistant Staphylococcus aureus, but they are rarely the original source of the pathogen. Dogs can become reservoirs for the bacteria and may even develop active infections, although most canine cases are thought to come from humans. The disease rarely spreads between people and animals, although the potentially deadly consequences warrant taking precautions to prevent transmission.
MRSA Occurence in Dogs
Staphylococcus bacteria are widespread in human populations worldwide, so pets encounter the pathogen during routine activities. Between 25 and 40 percent of people are carriers of the bacteria, although most of them do not develop an infection, according to the American Veterinary Medical Association. The bacteria lives harmlessly on the skin of most carriers, and only establish an infection if it enters through an open wound. Staph bacteria, including resistant strains, can colonize dogs, cats and other animals after contact with a human carrying the germs.
Identifying Staph Infection
Staph infections can create visible symptoms at the site of infection, or penetrate the body through the bloodstream and cause more widespread clinical signs. Superficial infections often appear as a red bump or swelling, similar to an insect bite, according to Oklahoma Cooperative Extension. An infected dog also may have trouble breathing or walking if the pathogen infiltrates joints or internal organs. Check your dog for cuts, scrapes and other open wounds several times a week. Keep an eye on any injuries and be ready to head to the vet if you notice swelling, reddened skin or other signs of infection.
Diagnosing Resistant Strains
MRSA produces identical symptoms to normal staph infections, so lab tests are required for a definitive diagnosis. They are essentially the same disease, although the resistant strains are much harder to treat. If your vet believes that your pet is suffering from a staph infection, he will take a sample culture and test it for resistance. Resistant strains of staph may be immune to one or more common antibiotics, including penicillin, cephalosporin and methicillin. This can make treatment more complex and expensive, and requires you to take extra steps to protect yourself at home.
When faced with a resistant strain of staph, your vet may attempt to determine the specific antibiotics that the bacteria is resistant to. Not every strain of MRSA is immune to all common antibiotics, so it's possible to find a weakness in their defenses through lab tests. Antiseptic shampoo and surgical removal of infected tissue are also viable treatment options, depending on the individual case. Continue to administer any medication as instructed by the veterinarian even if your dog appears to be recovered before the course is complete.
If your vet determines that your pet is carrying or infected with MRSA, you should isolate him from family and other pets. Wear disposable gloves when handling your pup and clean all surfaces regularly with a disinfectant, such as a diluted bleach solution. Wash all cloth material, toys and bedding that your dog had access to during the treatment. Use hot water and dry them on high temperature to kill lingering bacteria.
- Oklahoma Cooperative Extension Service: Methicillin-resistant Staphylococcus aureus (MRSA) Infection in Animals
- Texas A&M University Veterinary Medicine and Biomedical Sciences: Staph Infection and Methicillin Resistancde in Companion Animals
- USF Health: MRSA Transmitted Between Pets and Humans a Growing Problem
- American Veterinary Medical Association: Methicillin-resistant Staphylococcus Aureus
Quentin Coleman has written for various publications, including All Pet News and Safe to Work Australia. He spent more tan 10 years nursing kittens, treating sick animals and domesticating semi-feral cats for a local animal shelter. He graduated from the University of Delaware with a bachelor's degree in journalism.