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Comparing a dog’s mouth with a human’s mouth is sort of like comparing apples and oranges—really filthy apples and really filthy oranges. Both species’ mouths are hot, damp places teeming with roughly equal populations of bacteria. Neither would be described as clean, and any question of comparative cleanliness is irrelevant because so much of that bacteria is species-specific. Most of the germs in your dog’s mouth aren’t going to be a problem during a a big, wet doggie kiss. You’re more likely to run into trouble kissing another human than you are a dog, because bacteria from a person’s mouth will feel equally at home in yours.
Of course, not all bacteria is species-specific. Dogs and humans can and do transmit some germs to each other via the mouth, so if your dog is the type that likes to lick faces (is there any other type?), there are a few precautions you can take. One, try to keep your dogs from picking up any external bacteria by keeping them out of the trashcan (and away from rancid food), and away from wild animals (lest they contract rabies). Two, keep them healthy: up-to-date vaccines, good external and internal parasite control, regular teeth brushing, etc.
And then, pucker up!
While we’re at it, let’s tackle two more things we’re often told about canines: 1) Dogs lick their wounds and they heal very fast, and 2) Dogs don’t get as many cavities as humans. There are simple explanations for both. Licking the wounds gets rid of dead cells and dirt, just like when we wash our wounds. The immune system takes it from there.
As for cavities, they’re largely caused by the bacteria Streptococcus mutans. These bacteria feed on sugar, which is far more common in a human’s diet than a dog’s. Hence S. mutans prefers to live in our mouths, not Fido’s.
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Comments (20)
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But my dog eats poo and uses his tongue like it was toilet paper. I can’t believe that wouldn’t make his mouth dirtier than mine since his has feces in it.
And if you post back and tell me that there is feces in my mouth too, I will not be able to reply as I will (in the words of Adrian Monk) be rushed to the hospital where I will pray for the sweet relief that only death can bring.
*shudder*
posted by veetie on 3-4-2010 at 11:44 pm
The fecal-oral route is a very common route of infection (how do you think you have been colonized with your natural flora), so yeah veetie you most likely have had some degree of feces in your mouth like everyone else. Enjoy your weekend.
posted by Dagger on 3-5-2010 at 8:58 am
Veetie, I think the point was to contest the idea that dogs’ mouths are cleaner than humans.
Also, I am greatly annoyed when people post their reCAPTCHAs, but mine is Mints required. How perfect !!!
posted by Biolobri on 3-5-2010 at 9:46 am
LOL @ veetie’s comment!
posted by K on 3-5-2010 at 10:06 am
Along the same lines, people continue to believe this myth because it’s true that you’re more likely to get an infection from a human bite than a dog bite. Bad deductive reasoning, but there you have it.
Also, sorry Biolobri, but my reCAPTCHA – sources assume. HA!
posted by Kristin on 3-5-2010 at 10:35 am
The sickest I’ve ever been is when I picked up Giardia one summer while staying at Lake Tahoe. The CDC never determined the source, but they thought it was either from the water (which doesn’t seem likely as the outbreak stayed within our house) or from the dog playing in a creek!! I never touched that dog again (and I never drank the water again either….)
posted by Tracy on 3-5-2010 at 10:39 am
Yea, my dog licks her butthole.
There’s no way I’m letting her lick my face.
posted by Kelsey on 3-5-2010 at 11:23 am
On a complete other note from everyone else. I love the picture with the dog and baby. Whose are they, or is it just a random one?
posted by FlowerPower on 3-5-2010 at 12:46 pm
FlowerPower — That’s my daughter and dog. They work cheap! (http://jasonenglish1.com/category/dog-matters/)
posted by Jason English on 3-5-2010 at 2:02 pm
Oh, there are very, very few things in this world as cool as a dog and a child who get along. My dog helped with everything from potty training, laughter, bedtimes, wakeup times, ball playing, and, eventually, the death process, as we just lost him to cancer. I am so glad you are getting to enjoy this unique bond as well. :)
posted by Helenann on 3-5-2010 at 3:19 pm
… so what about a cat’s mouth? Granted, a cat isn’t likely to lick your face when you walk in the door (probably a good thing, considering all the varied and gross places they clean themselves), so this question is merely hypothetical.
posted by micx on 3-5-2010 at 6:23 pm
There’s another good reason that dogs do not develop cavities. If you look at human teeth, they are tight together with lots of nooks and crannies for food to be trapped and bacteria to grow. Dog teeth, on the other hand, are widely spaced and there’s comparatively fewer spaces for food to get trapped.
posted by cjung on 3-5-2010 at 7:20 pm
Dogs cleaning themselves and then licking your face is just too gross to think about!
posted by Libby on 3-5-2010 at 9:35 pm
THANK you for stating that it’s like comparing apples and oranges, because it really is. There’s also the factor that (most hygiene-conscious) people brush their teeth every day, whereas a dog can’t exactly pick up the toothbrush after he gets out of the shower.
Cat mouths, on the other hand, are utterly disgusting. If you have a cat that goes outdoors, imagine all the things he is tracking down and killing/eating, or even finding already dead and eating. Or, if you don’t have a cat that goes outdoors, either your cat is still finding indoor vermin OR there’s the fallback factor of cats being very prone to dental disease. So essentially if you don’t have your cat’s teeth religiously looked after by a vet, you’re looking at a mouth full of rotting choppers. Hence the reason vets and vet techs are way more cautious about cat bites than they are dog bites.
In any case, cat or dog, oral and dental health is as important to their well-being as it is to ours, so ideally you should get their teeth cleaned every year just like they get their annual checkup and shots. Just something to keep in mind.
posted by Amber on 3-6-2010 at 11:10 am
Trace: I also got Giardia one summer. It took doctors a month before figuring out what I had. It was horrible. I got lost in the woods and drank river water. Giardia is transmitted via animal fecal matter. Yeah gross, but the moral is, never drink unfiltered river water… and in my case, especially near the ocean… it’s travelled a long way before it got there.
posted by Trevor on 3-6-2010 at 12:36 pm
There is also Growth Factors in spit which promote healing and clear infection.
posted by Deej on 3-25-2010 at 10:17 pm
Yes, I know, I’m a geek!!! I can’t help but correct this, though: dogs technically don’t get cavities. They may get caries, but it’s not like what we get. I’ve done a lot of canine dentistry, and I’d be horrified if a human’s mouth was dirtier than that!
posted by Dental Vet Nurse on 4-8-2010 at 6:50 pm
Re Giardia: I read recently that EVERY SINGLE freshwater source in the US is now contaminated with it. I also read that filling a label-less clear plastic bottle with water and then laying it on top of metal (such as old foil or flattened cans) for 6 hours will sterilize it.
posted by Peach on 5-23-2010 at 7:00 pm
Re Giardia: I read recently that EVERY SINGLE freshwater source in the US is now contaminated with it. I also read that filling a label-less clear plastic bottle with water and then laying it on top of metal in direct sun(such as old foil or flattened cans) for 6 hours will sterilize it.
posted by Peach on 5-23-2010 at 7:00 pm
My dogs love to drink from small little rivers of water or puddles. They both got Giardia. The Vet said that if one had it the other one would so they only tested one of the two. I was never tested, can humans contract viruses and illnesses from dogs?
posted by Pam Davis on 7-15-2010 at 3:31 pm