Dogs can enrich our lives in many ways. They can relieve anxiety, reduce loneliness, make us more physically active and even lower our risk of cardiovascular disease, prolonging our lives, some research suggests.
But yes. They can also make us sick.
“Dog germs can cause a variety of illnesses, from mild skin infections to serious illnesses,” says Casey Barton Behravesh, a veterinarian at the CDC. Many people become infected after accidentally ingesting—yes, ingesting—dog feces, but infections can also be spread through bites, scratches, and even face licks.
The good news is that dog lovers can take simple steps to greatly reduce the risk of getting sick from their furry best friends.
There is no shortage of germs that dogs can transmit to people. They include bacteria such as salmonella, E. coli and campylobacter, which can cause gastrointestinal problems; parasites such as giardia, cryptosporidium, hookworms and roundworms, which can also cause abdominal problems such as diarrhea and stomach pain; and fungi, which can lead to infections such as ringworm, which can cause itching and ring-shaped rashes.
It is difficult to assess how many of these infections are transmitted by dogs each year. That’s because it’s difficult to trace diseases back to specific animals and collect this type of data, says Jason Stull, an assistant professor at the Ohio State University College of Veterinary Medicine.
Through bites, dogs can also transmit germs that cause serious illnesses, such as rabies, a virus that attacks the nervous system, and capnocytophaga, a bacteria that can cause serious illness, including sepsis. Both diseases can be fatal—but fortunately, they are quite rare, with rabies causing only one to three reported human infections per year in the United States and capnocytophaga infecting around 150 to 250 people.
Some people are more likely to get sick from dogs than others, including those who are pregnant, immunocompromised, over 65 or under 5, says Stull.
Puppies under 6 months of age are the biggest culprits in spreading disease-causing germs, he adds, in part because their immune systems are not fully developed.
How to stay safe
If you have a dog, you can reduce the risk of disease by ensuring he is fully vaccinated and receiving regular care from a veterinarian, says Dennis Horter, veterinarian and chief operating officer at CityVet in Dallas.
Veterinarians can also prescribe medications that reduce the chance of your dog harboring parasites, such as ticks and fleas, which can be transmitted from dogs to people and cause illness, adds Rebecca Greenstein, a veterinarian at Kleinburg Veterinary Hospital in Ontario. Always see your veterinarian immediately if your dog has diarrhea, she says.
“Keeping your dog healthy helps keep you and your family healthy,” says Barton Behravesh. Doing this is especially important if you or anyone else in your household is at high risk of developing illnesses.
Experts recommend not feeding raw meat to dogs, as it may be contaminated with bacteria that can spread to people. Research suggests there are no clear benefits of this diet for pets, and the studies “only highlight risks” that include the spread of salmonella, E. coli and campylobactersays Greenstein.
Wash your hands after petting or grooming your dog, says Barton Behravesh. And avoid kissing them anywhere on their body — yes, this can be difficult for some dog lovers — or letting them lick you on the face or any open scratches or wounds, advises Stull. Some people assume their dog’s mouth is clean. “It’s not,” he says. “It’s very easy for infectious organisms — bacteria, etc. — to move from the animal’s saliva into our bodies.”
If you are bitten, he says, clean the wound with soap and water and see a doctor.
Also clean up your pup’s poop. “I can’t emphasize this enough: pick up your dog’s feces,” says Greenstein. “Fecal contamination of grassy parks, sandpits, schoolyards and so on can pose a serious health risk, especially to children and people with weakened immune systems.”
But again, remember to wash your hands afterward, says Stull — because many people don’t. “We go out, we pick up the feces from the floor, we throw them in the trash, we don’t wash our hands,” he says. “Then let’s have lunch.”