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Home > Dogs > Is a Dog’s Mouth Cleaner Than a Human’s Mouth?

Is a Dog’s Mouth Cleaner Than a Human’s Mouth?

Dog Mouth

All dog owners are exposed to their pet’s saliva at one time or another, either through affectionate licks or a gentle bite. The expression, “A dog’s mouth is cleaner than a human’s mouth” may come to mind. But is this really the case? According to scientists and canine experts, the answer is no, a dog’s mouth is not cleaner than a human’s mouth.

In fact, the mouths and saliva of dogs naturally contain a large number of bacteria. While these do not present a problem for the animal, they can, in some cases, be dangerous for humans if they come into contact with people’s blood. Find out what these bacteria are, the risks for humans, any aggravating factors, and the right actions to take if a wound gets infected.


Why Are Dogs’ Saliva Not Cleaner Than Ours?

American Rottweiler dog play with the ball in the garden happy
Image by: nicolas.fontana, Shutterstock

You know that your dog uses their tongue every day, either to communicate, explore their environment, or lick themselves. Licking is essential for the animal because they are participating in a mode of communication. However, dogs tend to lick a lot of things.

As a result, dog saliva contains a large number of bacteria. Of course, the body of every living being contains billions of bacteria; they contribute to the well-being, digestion, and preservation of the immune system. But while some are used for the normal care of your pup’s mouth and entire body, others are potentially dangerous to humans.

The most famous bacterium that can be dangerous to humans and common in dogs’ mouths is Capnocytophaga canimorsus. Naturally present in the saliva of doggies but also that of cats and humans, it can cause severe infections in humans if it enters their bloodstream through a bite or licking a wound. The danger of this bacterium is zero for the animal because it comes naturally from their body. But when it is taken out of this context, it presents a significant risk and can become a pathogen.

Researchers have also found that dogs have another type of bacterium called Porphyromonas gulae, which can cause periodontal disease. Humans have a different strain of this bacterium, called Porphyromonas gingivalis.

In addition, other Harvard researchers have found more than 615 different bacteria in human mouths, compared to 600 in dogs. This slight difference may have reinforced the myth that dogs’ saliva is cleaner than ours, but that would be comparing apples to oranges. The mouths of dogs and humans are full of germs, but these types of bacteria are different. So, in essence, you could say that a dog’s saliva is as dirty as ours.

Happy Dog
Image Credit: Branislav Nenin, Shutterstock

What Are the Risks of Contracting Diseases From a Dog Kiss?

As humans, our skin protects us from infections by forming a natural barrier against the vast majority of viruses, bacteria, and microorganisms of all kinds. However, bacteria can pass into our blood and spread throughout our bodies once we have a wound. The dog can therefore transmit them to us by a bite that crosses the skin, by scratches that cause bleeding, or even via a lick on an unhealed wound.

The bacteria that is most commonly found in a dog’s mouth is Pasteurella canis. Also, dogs can transmit the bacterium Capnocytophaga canimorsus through a bite, which can lead to severe bacterial infection in humans. Moreover, the rabies virus is the most serious infection that dogs can transmit through their saliva.

In addition, a dog can eat food contaminated with Salmonella or E. coli, and these pathogens could be passed to humans if the dog’s slime gets into your mouth.

Are There Any Aggravating Factors in Dog Saliva?

It seems that certain factors are aggravating in the case of contact with certain bacteria through the saliva of a dog:

  • Being immunocompromised: A weakened organism will be less able to defend itself naturally against external attacks and will therefore be more vulnerable to bacteria.
  • Children under five or adults over 65: These groups of people are more vulnerable to infections.
  • Having wounds or lesions: Wounds and lesions are gateways for bacteria, which may enter the bloodstream through them.
happy little girl hugging her golden retriever dog
Image Credit: Tatyana Vyc, Shutterstock

What to Do If You Suspect an Infection

The risk of contracting dangerous bacteria through a dog’s saliva is rather low in healthy individuals. However, if you get bitten deeply by a dog or licked on a wound, immediately wash the lesion with clean water and soap to disinfect it thoroughly. Then, seek medical attention, no matter how minor the wound may look.

  • Tips: To avoid any type of infection, wash your hands thoroughly after touching your dog and any other parts of your body (arms, legs, face) that they have licked. Avoid touching a child, a weakened person, and food after such contact without prior washing. Finally, don’t let your dog lick your face or any damaged skin.

How to Keep Your Dog’s Mouth Clean

hand brushing dog's teeth
Image by: Littlekidmoment, Shutterstock

You can’t remove all bacteria from your dog’s mouth, but you can improve their oral hygiene with a few actions:

  • Brush your dog’s teeth at least twice a week.
  • Use toothpaste specially designed to reduce plaque.
  • Give food made to improve the dog’s dental health.
  • Offer dental treats that have the Veterinary Oral Health Council seal of acceptance.
  • Schedule regular veterinary dental cleanings.

divider-dogFinal Thoughts: Dog Mouth Cleanliness

Your beloved dog’s saliva certainly isn’t cleaner than yours, but the bacteria that it contains is generally not harmful to healthy people. However, in some cases, it is possible to contract serious illnesses through the saliva of dogs, though this risk remains low. Still, it’s best to avoid big kisses with your dog and to clean your hands after each handling. But as dog lovers, we know that this is much easier said than done!

Featured Image Credit: JACLOU-DL, Pixabay

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