Is It Safe to Let Your Dog Lick Your Face?

Anyone who owns a dog will recognise the pleasure of arriving home to an ecstatic welcome: a frantically wagging tail followed by eager, if rather face-soaking, licks. Some people gently push their dog away to deter face licking, while others enjoy the display of affection and may even present pursed lips for a canine kiss.

It is an undeniably endearing sight.

Yet consider everything your four-legged friend may have licked during the day: food and water bowls, paws, toys and chews - perhaps even their bottom and genitals. Those adorable kisses may suddenly seem rather less enticing.

Whatever their pets have been licking, plenty of owners are so fond of their dogs that they are prepared to ignore the possible hygiene concerns.

Why dogs lick people and themselves

Licking also matters to dogs, as it is an instinctive part of canine behaviour. Repeated mouth licking can be a subtle indication of stress or fear, particularly alongside pinned-back ears and a tense facial expression. Indeed, the rate at which dogs lick their lips can be used to assess their welfare during training and while they are housed in kennels.

Dogs may also lick their lips in response to human emotions. Research indicates that they are empathetic, able to identify emotions in people and other dogs through visual and auditory signals. One study found that dogs licked their lips more often when shown angry human faces.

Lip licking is therefore a natural canine instinct, including in interactions with their human companions. For people who share their home with a dog, being licked is routine, and many dogs will attempt to lick their humans' faces and mouths.

Nearly half of dog owners say their dog has licked their face. But considering many dogs' enthusiasm for eating things their owners may find unappealing - a quick poo snack, anyone? - is allowing a dog to lick your face hygienic, or even safe?

What hides within

People generally adore their dogs, and the companionship and affection they provide can greatly support owners' wellbeing and mental health. Nevertheless, canine saliva may do more harm than good for some people.

Anyone who is immunocompromised, has an open wound, or owns a dog that supplements its diet with coprophagia (eating poo), would be best avoiding face licks.

Dogs' mouths may contain a variety of microorganisms that usually pose little risk to humans. In uncommon instances, however, zoonoses - infectious diseases transmitted between species - can pass from dogs to people through bites, licks and scratches.

In most cases, contact with dog saliva does not make people unwell. Many people live with their pets, including all the licking, without experiencing any health problems.

There have, however, been rare instances in which contact with dog saliva has made people seriously ill. For instance, Capnocytophaga canimorsus, a bacterium present in the mouths of up to three quarters of otherwise healthy dogs and cats, has led to life-threatening sepsis.

Other microbes, including Pasteurella multocida, can be transmitted through exposure to dog saliva and may cause serious conditions, including meningitis.

Those thought to face the greatest risk from zoonotic infections include immunocompromised people, very young children, older adults and pregnant women.

If you belong to one of these groups, avoiding dog licks is advisable. Dog owners at risk should take further precautions too: clean surfaces regularly, reduce contamination of household items and maintain meticulous household hygiene at all times, particularly following contact with animals.

Antibiotic resistance is widely recognised as a major global health issue. Dog saliva may be a source of bacteria carrying antibiotic-resistant genes, and these bacteria can colonise humans after exposure to saliva.

However, a 2023 German study involving 2,800 hospital patients and their companion animals confirmed "that the sharing of multidrug-resistant organisms between companion animals and their owners is possible", while identifying only a small number of cases. The researchers consequently concluded that "cat or dog ownership isn't an important risk factor for multidrug-resistant organism colonization in hospital patients."

So, although licking by a dog might contribute to the spread of antibiotic resistance, it is unlikely to do so.

Can dog licks offer health benefits?

Despite the possible health risks, could dog licks provide any benefits?

Historical records indicate that animal saliva was once used in wound healing, and some dogs were specifically trained to lick open wounds. But no research suggests that letting animal companions lick wounds helps them heal.

On the contrary, allowing an animal to lick an open wound may increase an owner's risk of infection.

The human-dog relationship can bring other potentially therapeutic advantages. Animal-assisted therapy supports people experiencing a range of difficulties, including anxiety, eating disorders and trauma. Cuddling or stroking a dog, for example, may help patients feel calmer while reducing blood pressure and heart rate.

Dog owners commonly gain from greater physical activity and social contact, as well as companionship and better mental health. Licking, though, is not necessary for a close relationship between a person and a dog.

For most people, allowing a dog to lick them is probably safe within reason. Sound management, healthcare for both you and your dog, and excellent hygiene are likely to make the risks of an occasional lick minimal. Still, making “not on the mouth” the rule is sensible for everybody's safety.

Jacqueline Boyd, Senior Lecturer in Animal Science, Nottingham Trent University

This article is republished from The Conversation under a Creative Commons licence. Read the original article.