Cat bites to the hand cause infection in one out of every three cases.

Feline teeth inject bacteria deep into tissue and joints, paving the way for a nasty infection to develop, a MayoClinic news release reported.

"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. The cats' teeth are sharp and they can penetrate very deeply, they can seed bacteria in the joint and tendon sheaths," senior author Brian Carlsen, M.D., a Mayo Clinic plastic surgeon and orthopedic hand surgeon said in the news release.

"It can be just a pinpoint bite mark that can cause a real problem, because the bacteria get into the tendon sheath or into the joint where they can grow with relative protection from the blood and immune system," he said.

Two-thirds of all cat-bite related patients require surgery; the majority of victims are middle-aged women. The bacteria introduced by a cat bite are difficult to treat with modern antibiotics.

To make their findings the team looked at 193 Mayo Clinic patients who had received cat bites to the hand between 2009 and 2011. Fifty-seven of those patients were hospitalized and stayed in the hospital for an average of three days. Thirty-eight of those patients had to have their wound surgically flushed out and infected tissue removed in a process called debridement. Eight of the patients required several operations or reconstructive surgery.

"Of the 193 patients, 69 percent were female, and the mean age was 49. About half of the patients first went to the emergency room, and the others went to primary care. The mean time between the bite and medical care was 27 hours," the news release reported.

Patients who received bites directly over their risk or a joint were found to be at a higher risk of serious infection.

The researchers concluded cat bites should be taken seriously both by medical professionals and patients. iIndividuals should seek medical attention immediately if inflamed skin and swelling occurs after a cat bite.

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

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