By Dr. Karen Becker DVM
In a survey of 2,089 U.S. pet owners, more than half (52%) said they’re just fine with their dog licking, or “kissing,” their face.1 Another survey revealed that 52% of dog owners smooch their dog more than their significant others, while 61% kiss their dogs on the mouth.2
So it’s clear that many people who share their lives with dogs also share their affection with them — an understandable concept, since many regard their pet as part of the family.
From your dog’s point of view, licking your face is likely a sign of affection. Mother dogs lick their pups from the moment they’re born in order to clean them and stimulate breathing. Puppies will also lick around their mother’s mouth, which may be an instinct carried over from their wolf ancestors, which lick the mouths of adult wolves to trigger regurgitation of partially digested food.3
It’s possible, too, that your dog likes the way your skin tastes or licks your mouth because it contains some leftover food — as is often the case with children. Most likely, though, it’s a friendly gesture your dog uses to show you he loves you.
In dog packs, subordinate members often lick the dominant members to promote pack harmony, and doing so releases endorphins that promote feelings of pleasure.4 Giving your face a lick is probably an extension of this.
Can Kissing Your Dog Make You Sick?
In the majority of cases, a quick kiss from your dog is harmless and will serve to further cement your bond together. It is possible, though, that it could also expose you to bacteria or viral diseases that could, theoretically, make you sick. You may have also seen occasional cases highlighted in the media where a lick from a dog turns catastrophic.5
In Germany in 2019, a 63-year-old man died after becoming infected with capnocytophaga canimorsus bacteria. The bacteria are common in the mouths of dogs and cats, and it’s believed he was exposed when his dog licked him.
Severe and fatal infections occur more often in people with compromised immune systems, but the man in this case was previously healthy. He experienced flu-like symptoms, which progressed into severe sepsis and purpura fulminans, a condition involving blood spots, bruising and discoloration of the skin that can progress to necrosis.
“Pet owners with banal, for instance flu-like, symptoms should urgently seek medical advice when symptoms are unusual,” the researchers wrote in a case report in the European Journal of Case Reports in Internal Medicine.6 This is especially true if you’ve been bitten by your pet, even if it’s just a small nip.
In a separate case in 2019, a woman in Ohio had her hands and legs amputated due to an infection with capnocytophaga canimorsus, which she contracted from her German shepherd licking an open cut.7 According to the U.S. Centers for Disease Control and Prevention (CDC), capnocytophaga have been detected in up to 74% of dogs, and it is a normal part of their flora.8
Another case occurred in 2018, resulting in an otherwise healthy 48-year-old losing his hands and feet due to capnocytophaga canimorsus. While doctors aren’t sure where he contracted the bacteria, they hypothesized that it was due to a dog lick.
Still, Dr. Silvia Munoz-Price, an infectious disease physician who treated the man doesn’t believe there’s cause for alarm: “I have a dog. Many people have dogs, and most of us will never have problems with infections related to our pets.”9 It’s important to understand, however, that capnocytophaga canimorsus rarely pose a risk to humans.
“[I]n the wrong place, at the wrong time, in the wrong patient … it can lead to severe infections,” Dr. Stephen Cole, a lecturer in veterinary microbiology at the University of Pennsylvania School of Veterinary Medicine, told CNN, “but very, very rarely.”10 “Every time your dog licks you,” he added, “you may come into contact with this bacterium, but the vast, vast, vast majority of times, that causes absolutely no problem.”11