02/12/2014

Ask your mail carrier about dog bites. They'll tell you it's an occupational hazard. According to the American Humane Society, about 4.7 million dog bites occur in the U.S. each year.

What you don't hear much about are cat bites. There aren't nearly as many but, according to researchers at the Mayo Clinic, cat bites are extremely dangerous.

Their jaws may be tiny compared to a dog's but their tiny teeth can do real damage, injecting bacteria deep into joints and tissue, perfect breeding grounds for infection.

One indication of the danger is the required treatment. A Mayo Clinic study covering three years shows that one in three patients treated for a cat bite had to be admitted to a hospital. Of those requiring a hospital stay, two-thirds needed surgery.

The study found that middle-aged women were the most common cat bite victims.

Perfectly-designed injectors

Cats' mouths contain no more bacteria than do dogs', the researchers are quick to point out. It's simply the fact that cats' sharp little fangs are perfectly designed to inject that bacteria deep into tissue.

“The dogs’ teeth are blunter, so they don’t tend to penetrate as deeply and they tend to leave a larger wound after they bite,” said senior author Brian Carlsen, M.D., a Mayo Clinic plastic surgeon and orthopedic hand surgeon. “The cats’ teeth are sharp and they can penetrate very deeply, they can seed bacteria in the joint and tendon sheaths.”

It doesn't take much of a wound to cause the damage. Just a pinpoint bite mark, says Carlsen, can inject bacteria into the tendon sheath or into the joint where they can grow with relative protection from the blood and immune system.

The bacteria from a cat bite can include a strain common in animals that hard to treat in humans because it is particularly hard to fight with antibiotics.

Unpleasant treatment

Patients admitted to a hospital for a cat bite often must have their wounds surgically irrigated, or flushed out, and infected tissue removed, a procedure known as debridement. In the Mayo Clinic study eight of 193 patients needed more than one operation, and some needed reconstructive surgery.

The wrist or any joint in the hand is usually the worst place to receive a bite. In the study it had a higher risk of hospitalization than wounds over soft tissue. A hand, unfortunately, tends to be where a cat will strike, as the victim tries to pet the animal or offer food.

Why would cats bite the hand that feeds them? That's probably an unanswerable question. Suffice it to say that cats can have personalities as varied as human – from Mother Teresa to serial killer.

Infants and cats don't mix

More so that dogs, cats can be highly aggressive when the mood strikes them. They're hard-wired to use teeth and claws to hunt and defend themselves. While your cat may turn up its nose at the fanciest commercial cat food it nonetheless may take great delight in stalking, pouncing on and devouring small animals that enter its domain. If there are no small animals about, your cat may decide to stalk you or other family members instead.

That's why if you have children in a household with a cat, don't encourage rough play, scratching or biting. Things can quickly get out of hand.

Most importantly, infants should never be left alone with a cat. Any cat, no matter how seemingly docile and domesticated, can respond aggressively when certain instincts are triggered. Infants can be severely harmed in just a few seconds. A photo of a baby sleeping with a cat may be cute but a follow-up photo of the stiches won't be as attractive.

Cat fanciers should always be on the lookout for subtle changes in your cat's behavior that could indicate a change in mood is occurring. In particular, dilated pupils and rippling skin could indicate your cat is ready to pounce.

When your cat does, in fact, bite the doctors at the Mayo Clinc say you need to take it seriously. When patients have inflamed skin and swelling, it probably will require aggressive treatment.

“Cat bites look very benign, but as we know and as the study shows, they are not,” Carlsen said. “They can be very serious.”