Can My Dog Make Me Sick?

Q: I treat my dog as if she’s part of the family; she sleeps in my bed, licks my face, even shares my ice cream from time to time. Should I be worried about getting sick?

Dogs can enrich our lives in many ways. They may ease anxiety, reduce loneliness, make us more physically active and potentially even lower our risk of cardiovascular disease, lengthening our lives, some research suggests.

But yes. They can also make us sick.

“Germs from dogs can cause a variety of illnesses, from minor skin infections to serious illnesses,” said Dr. Casey Barton Behravesh, a veterinarian with the Centers for Disease Control and Prevention. Many people become infected after accidentally ingesting — yes, ingesting — dog feces, but infections can also be transmitted via dog bites, scratches and even licks on the face.

The good news is that dog lovers can take simple steps to greatly reduce their risk of being sickened by their furry best friends.

Dog Diseases

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 woes; parasites such as giardia, cryptosporidium, hookworm and roundworm, which can also cause abdominal issues like diarrhea and stomach pain; and fungi that can lead to infections like ringworm, which can cause itchy, ring-shaped rashes.

It’s hard to gauge how many of these infections each year are transmitted by canines. That’s because it’s hard to trace illnesses back to specific animals and collect that kind of data, said Dr. Jason Stull, an assistant professor at the Ohio State University College of Veterinary Medicine.

Through bites, dogs can also transmit germs that cause serious diseases, such as rabies, a virus that attacks the nervous system, and capnocytophaga, a bacteria that can cause serious illnesses, including sepsis. Both illnesses can be fatal — but thankfully, they are quite rare, with rabies causing only one to three reported human infections per year in the United States and capnocytophaga infecting an estimated 150 to 250.

Some people are more likely to get sick from dogs than others, including those who are pregnant, immunocompromised, over 65 or under 5, Dr. Stull said.

Puppies under 6 months of age are the biggest culprits in spreading disease-causing germs, he added, in part because their immune systems are not fully developed.

Staying Safe

If you own a dog, you can reduce your risk of illness by making sure it’s fully vaccinated and that it receives regular care from a veterinarian, said Dr. Dennis Horter, a veterinarian and chief operating officer of CityVet in Dallas.

Vets can also prescribe medications that reduce the chance that your dog will harbor parasites, as well as ticks and fleas, all of which can be transferred from dogs to people and cause illnesses, added Dr. Rebecca Greenstein, a veterinarian at Kleinburg Veterinary Hospital in Ontario. Always see your vet right away if your dog has diarrhea, she added.

“Keeping your dog healthy helps to keep you and your family healthy,” Dr. Barton Behravesh said. Doing so is especially important if you or any other people in your household are at high risk for developing illnesses.

Experts caution against feeding raw meat to dogs, because it can be contaminated with bacteria that can then spread to people. Research suggests there are no clear benefits of the diet for pets, and studies “only underscore the risks,” Dr. Greenstein said, which include the spread of salmonella, E. coli and campylobacter.

Wash your hands after petting or caring for your dog, Dr. Barton Behravesh said. And avoid kissing them anywhere — yes, this might be hard for some dog lovers — or letting them lick you on your face or on any scratches or open wounds, Dr. Stull advised. Some people assume that their dog’s mouths are clean. “They’re not,” he said. “It’s very easy for infectious organisms — bacteria, et cetera — to move from the animal’s saliva into our bodies.”

If you get bitten, he said, clean the wound with soap and water and contact a doctor.

Clean up after your pup, too. “I can’t emphasize this enough: Pick up your dog’s poop already,” Dr. Greenstein said. “Fecal contamination of grassy parks, sandboxes, schoolyards and so forth can pose a serious health risk, especially to children and those with weakened immune systems.”

But again, be sure to wash your hands afterward, Dr. Stull said — because many people do not. “We go out, we collect the poop off the ground, we throw it in the trash, we don’t wash our hands,” he said. “We then go and have lunch.”