Did I Get it From My Pet?

Photo: Andrew Lightman

One of the questions veterinarians I often get asked is whether our pet dogs and cats carry any diseases that a human could catch. The answer is yes, although it happens very rarely and the risk is very low. Diseases that can be passed from animals to humans are called “zoonotic.” I thought it would be worthwhile to review some of the important zoonotic diseases. I also wanted to touch on some of the diseases that get a lot of attention, but are actually not a big risk.

Let’s start with the elephant in the room, Ebola. I think everyone has probably heard the story of the woman with Ebola whose dog was euthanized because of concerns that her dog might carry or spread Ebola. There was also the case of the healthcare worker in Dallas whose dog was quarantined when she came down with Ebola. Can dogs or cats get Ebola? Can dogs or cats give Ebola to people? According to the U.S. Centers for Disease Control and Prevention (CDC), there are no reported cases of dogs or cats becoming sick with the Ebola virus or of being able to transmit it to people. This includes areas in Africa where Ebola is present. While we are still studying and learning about this devastating virus, there is currently no reason to believe our dogs or cats are at risk for catching or spreading Ebola.

Another well known human disease that people worry about with their pets is Methicillin-Resistant Staphylococcus Aureus, or MRSA (usually pronounced “mur-sah”). MRSA is a type of bacteria that can be difficult to treat because the bacteria has become resistant to certain types of antibiotics. Not every human or animal that becomes exposed to MRSA becomes ill (only a small percentage, actually), and people with a weakened immune systems are more likely to become infected. While it was originally thought that humans could pass MRSA to animals, but animals could not pass it to humans, it now appears that it can pass from human to animal or from animal to human. Speaking anecdotally, it extremely rare to see MRSA in our pets. However, if you are concerned about a possible MRSA infection in your pet, talk to your veterinarian. If you are worried about a MRSA infection in yourself, talk to your physician!

Toxoplasmosis is another zoonotic disease that many people have heard of. Toxoplasmosis is a microscopic protozoal parasite that can cause illness in pregnant women or immunocompromised people. Cats can be a source of infection for people, but so can eating undercooked or raw meat (especially pork), eating raw or unpasteurized milk, or ingesting cysts picked up from the environment. In fact, you are more likely to get toxoplasmosis from eating undercooked meat than from your cat. In addition, infected cats only shed cysts for a short time, so they are only a source of infection for a brief period. Nevertheless, individuals at risk can protect themselves by avoiding cleaning the litter box if possible, or by cleaning the box daily, wearing gloves when cleaning the box, and washing their hands afterwards. If you are worried about toxoplasmosis in your cat, talk to your veterinarian.

Ringworm is a good one to cover, too. Ringworm is actually not caused by worm, but by a fungus. Infection with this fungus can cause itchy, red rashes (sometimes with a red ring) in people. People can catch ringworm from the environment and also by coming into contact with an infected dog or cat. Ringworm is most common in young cats, but can infect dogs and cats of all ages. Ringworm in pets can have many different appearances, but most often causes patchy areas of hair loss and crusting lesions. However, there are many other more common diseases that can cause similar skin lesions in cats and dogs, including allergies, bacterial skin infections, and fleas. Therefore, if you are concerned about ringworm in your pet, have your veterinarian examine your pet first before assuming it is ringworm.

I don’t have enough space to cover all the possible zoonotic diseases of dogs and cats, but I do have some tips for preventing problems. First, practice good hygiene. Wash your hands after handling your pet or pet waste, especially before eating. Second, remember healthy pets are less likely to carry disease. Have your pet examined regularly by your veterinarian, keep their vaccinations current, and use monthly parasite preventatives. Third, keep yourself and your family healthy, since people with healthy immune systems are less likely to be infected. Lastly, talk to your veterinarian if you see symptoms of disease in your pet. With these simple precautions you can keep your whole family, both humans and our canine and feline family members, healthy and happy!

Born in Washington DC, Dr. Keith de la Cruz is currently the Treasurer/Secretary of the Virginia Veterinary Medical Association and is a Past President of the Northern Virginia Veterinary Medical Association.  He is newest associate veterinarian at AtlasVet (1326 H St NE).