You might have heard that a dog’s mouth is cleaner than yours, no matter how fastidious you are about dental hygiene.
Regardless of hygiene, though, we humans have somewhere between 400 and 500 different types of bacteria living in our mouths at any time. These bacteria are completely normal and healthy for us, so they are nothing to get worried about. Dogs have about 400 types of their own.
The bacteria living in their mouths are wildly different than those living in ours, however. Only about 15 percent of the bacteria living in a dog’s mouth is the same as that which lives inside our own.
So when you consider the cleanliness of a dog’s mouth and what happens if you swallow dog saliva, that’s something that has to be taken into account.
Your body uses and works with your bacteria. Since most of the bacteria in a dog’s mouth is foreign, your body won’t recognize it, and as a result you may get sick. Dog saliva can contain infectious bacteria and harmful parasites, especially if they’ve just been eating rotten meat or killing rats.
However, actually contracting something is exceedingly rare, and in most instances even if you swallow dog saliva you will be completely fine. I’ve been licked on the lips a few times by my overzealous dogs, and while admittedly purely anecdotal- I’m still here!
Dogs lick their wounds, just like most other animals. Wounds are great entrances for infectious diseases, so how can a dog lick its wounds and not make them worse? Doesn’t that mean that he can lick your wounds clean, too?
This myth came from an observation that originated hundreds of years ago. In some ancient societies, dogs did help clean out human wounds. But if dogs have so much bacteria in their mouths, how could this possibly work?
A dog’s saliva has antibacterial properties for itself. It can lick its wounds clean (as long as they aren’t severe) because its body has evolved in such a way that its saliva is both a wash and an antiseptic.
Those same antiseptic properties don’t apply when it comes to humans, due to the amount of bacteria that is foreign to our bodies.
Your dog licks and kisses you all the time and you never have a problem, so how can you get sick from dog saliva? Basically, any foreign microbe can make you sick if your immune system can’t deal with it.
The full answer is a little more complex.
A single lick from a dog can leave millions of bacteria on your skin or in your mouth. Much of the time, our immune systems and our bacterial arsenals handle foreign ones just fine.
Even though a dog’s mouth contains things like salmonella and E. coli, as well as parasites like Cryptosporidium, they don’t usually transmit these germs in amounts large enough to cause infection in average, healthy adults.
What happens if you swallow dog saliva if you’re a pregnant woman, have a baby, or have a compromised immune system? The chances of an infection go up quite a bit, so you should try to avoid letting your dog lick your face under these circumstances.
The same is true if your dog licks an open wound or skin with acne.
Quite likely, nothing will happen except feeling a little grossed out that you swallowed dog spit.
If you’re healthy, the immune system will probably deal with any harmful organisms before you even realize they were there.
However, there are stories where people did get sick from their dog’s saliva. Some got sick because a dog licked an open wound. In other cases, how people contracted the infection is less clear.
When dog saliva comes into contact with mucous membranes, including those in your nose and mouth, infectious bacteria can enter your bloodstream the same as it can when your dog licks an open wound.
Usually a bit of soap and water after being licked will be enough to clean the area, but if you want to be extra cautious, you can always use a disinfectant like Betadine or Bactine.
The most common illnesses you can catch from your dog are parasitic rather than bacterial or viral. Bacterial infections are rare, but are often quite serious when they happen. A man from Wisconsin lost both his arms and legs due to a blood infection he caught from a dog.
An Australian woman ended up in the hospital in septic shock after her dog licked a burn she got on her foot. She had actually forgotten she had the burn – it was that mild – until her dog licked it and she got sick.
You can also suffer an allergic reaction to your dog’s saliva whether you swallow it or not. Dog saliva contains a protein to which many people are allergic.
You might have a mild reaction such as a light rash, or you might develop a more severe reaction such as hives, dizziness or trouble breathing.
You might not even realize you’re mildly allergic to your dog until you swallow some of its saliva. Everyone has trouble connecting dots sometimes, and you may not have put specific symptoms together with your dog and its saliva until you swallow some of it.
If you take your dog to get its annual vaccines and it doesn’t come into contact with wild rabid animals, there’s virtually no risk that you’ll contract the rabies virus from your dog’s saliva- even if you swallow it.
Besides that, the virus has to find a direct route into your bloodstream to make you sick.
Generally, that requires a bite, but the odds of animals transmitting rabies at all are so small that between the years of 1990 and 2005, the U.S. only recorded 47 rabies cases– and not all of them came from infected animals.
The chances that you’ll get rabies from swallowing dog saliva are so remote they’re almost nonexistent, so there’s really no need to worry about it.
The fact of the matter is that, while you can get sick from swallowing dog saliva, the chances of that actually happening are extremely low.
If you ask an expert, “What happens if you swallow dog saliva?”, they’ll tell you about the many things that could happen and that it’s probably not the best idea to let your dog give you kisses all over your face.
It is technically possible to become ill from swallowing dog saliva. After all, a dog’s mouth isn’t typically the cleanest place since they tend to eat things like maggots and poop. As such, a dog’s spit will contain its fair share of nasty bacteria and parasites.
Some people may also have allergic reactions to the chemicals in dog saliva. If you’re pregnant, sick or have a compromised immune system, you may also want to hold off on smooches with your pooch for the time being.
However, if you are otherwise healthy and fit it’s very unlikely that you’ll catch anything from dog saliva. For most dog owners, letting their dogs lick and kiss them far outweighs the tiny possibilities of getting sick, even if they know about potential dangers.
Heather Abraham is an owner of two dogs, one cat, a leopard gecko, and a parrot (who her dad still cannot teach bad words to), and an avid blogger. From the time she was a young girl, she always felt a connection with pets. She brings her love of every type of pet to you, with information on animal nutrition, medication, toys, beds, and everything else in between. Along with newly-on-board veterinarian DVM editor Elena, she puts pups first while offering other various fun tidbits along the way.