Maybe Mom was right. Letting the dog lick your face is probably not the best idea. Advances in medical diagnostic tests now show that pets can transmit many diseases to humans, and such animal-to-human infection could be more common than anyone thought.
However, that doesn’t mean having pets is a bad idea. Rather, it’s important for families to choose the right type of pet and use some guidelines to keep human owners healthy, according to a new report from scientists at Ohio State University and Canadian researchers. The analysis is based on a review of more than 500 studies.
According to the report, published in the Canadian Medical Association Journal, there are nearly 20 different diseases that are commonly acquired from pets, including salmonella, E. coli, and roundworms. Different species of pets, such as dogs, cats, fish, or rodents, carry different types of disease. The animals’ ability to transmit disease also depends on their stages of life. For example, adult cats and dogs may be less likely to shed harmful organisms compared to kittens and puppies.
Likewise, a human’s ability to contract an infectious disease can depend on the strength of his or her immune system. Those most likely to catch diseases spread by animals (zoonotic diseases) are those with weakened immune systems, pregnant women, and the very young or old.
Families should discuss their zoonotic disease risk with their family doctor or their pet’s veterinarian, says Jason Stull, assistant professor of veterinary preventive medicine at Ohio State.
“Surveys suggest that most veterinarians and physicians do not regularly discuss zoonotic disease risks with clients, patients or each other,” Stull says. “That needs to change if we are going to effectively reduce pet-associated diseases. It’s all about safe pet ownership. There are very few situations in which a person couldn’t or shouldn’t have some type of pet if they wish. It’s about matching the right species with the right person and taking the appropriate precautions.”
Diseases that can be transmitted to humans from dogs include ringworm, salmonella, rabies, giardiasis, lyme disease, and MRSA (methicillin-resistant Staphylococcus aureus). Cats can transmit such diseases as hookworm and ringworm although one of the most serious is toxoplasmosis, which can cause health problems in a fetus if contracted during pregnancy.
“Pets do so much good for people in terms of mental, physical, and emotional health,” Stull says. “But at the same time, they can transmit diseases to us. Physicians, veterinarians, and the public have to work together to make sure the benefits outweigh the risks.”
The study, which was co-authored by researchers at Children’s Hospital of Eastern Ontario and Ontario Veterinary College, was funded in part by the Canadian Institutes of Health.