Infection Files: Salivary facts: Our pet pals can carry risks
By Dr. Claire Panosian Dunavan
Posted: 05/15/2011 12:37:04 AM PDT
My friend Gretchen was horrified, although she tried not to show it.
Not long ago, she arrived at our house wearing a spring dress and strappy sandals. Cut flowers in the living room matched her pretty outfit. The dining room table was set. Delicate aromas wafted from the kitchen.
In other words, she and I were about to enjoy a lunch that would have made my mother proud, until...
Our Cavalier King Charles spaniel bounded in and started licking Gretchen's legs like a Latin lover on steroids.
Oops. Maybe I should have warned our guest. Forget "Sit!" After years of training, Ollie still goes bonkers when he smells shaving cream.
Finally, my husband put him in purgatory (the laundry room) to stop his salivary bath of Gretchen's freshly-groomed gams.
Which is all by way of raising an earthy issue. When it comes to pet licks and nips, what are the principal risks?
Years ago - before widespread vaccination of American dogs - the answer might well have been rabies. This tiny speck of RNA shed in animal saliva is arguably the most malevolent virus known to man.
Today, animal rabies remains alive and well in our land but common hosts are bats, raccoons, skunks, foxes, and coyotes - fortunately, not the kind of creatures we usually cuddle.
On the other hand, many beasts humans love - most notably dogs and cats - harbor an oral germ named Pasturella multocida. Another single-celled resident of canine mouths is Capnocytophaga canimorsus. These two euphonious bacteria are among the leading "baddies" inoculated by dog and cat bites (the sharp, pointy teeth of cats, in particular, can drill a super-nasty infection).
What happens next? In a few unlucky victims, Pasturella and Capnocytophaga travel from their initial site of attack into blood or other, remote tissues. Both organisms have been known to cause high-grade sepsis and "endocarditis," a life-threatening, sometimes recalcitrant infection of human heart valves. In certain individuals, curing the microbe-laced "vegetations" of endocarditis requires not just weeks of intravenous antibiotics but surgical valve replacement as well.
OK, so bites are bad news, you've probably decided by now. Can simple animal licks also yield evil outcomes? Well, yes - once in a while. If you scan the medical literature, the stories are rare, but they're there - especially in patients with a unique vulnerability or "portal" of infection.
In one published case, a diabetic man suffered a festering Pasteurella abscess of his spine - like a heart valve, another tricky site to treat - after his dog licked his chronic toe ulcer. An Australian woman developed Capnocytophaga sepsis after her dog tongued a minor skin burn (she survived, but not before losing all her fingers and toes). Several cases of meningitis (a potentially deadly infection of membranes covering the brain) have followed lashings of pet saliva.
In each of these incidents, the animal's mouth swab grew the identical species recovered from the patients' spinal fluid, blood, or bone.
The most exotic report? I'll go with the patient with a chronically-perforated eardrum who ended up with Pasteurella meningitis after his dog licked his ear.
Back to everyday life. After reading these grisly tales, did I offer my friend Gretchen an antibiotic? Nope. Have I tried to cure Ollie of his mild, er, fascination with my own toes? No.
Along with vets and other experts, I believe the vast majority of dog and cat licks in healthy people are harmless.
But would I change my tune if I were diabetic or chronically ill with an open sore or healing cut or incision? You betcha.
Dr. Claire Panosian Dunavan is an infectious diseases specialist and a professor of medicine at the David Geffen School of Medicine at UCLA. She can be reached at firstname.lastname@example.org
Article courtesy of: The San Gabriel Valley Newspaper Group
Permission Given: Editor, Catherine Gaugh