• Mayo Clinic Q and A: What is cat scratch fever?

a smiling young man lying on his back on the floor, with a big fluffy cat on his chestDEAR MAYO CLINIC: My cat scratched me while I was trimming his claws and the wound later became infected. Are cat scratches a special concern?

ANSWER: A bite or scratch from a cat carries particular risks, and infection is common. Cat scratch disease (or cat scratch fever) is a specific type of bacterial infection that occurs when a cat bites or scratches hard enough to break the skin’s surface or licks an open wound. It’s estimated that 40 percent of cats carry this particular bacterium, usually after an exposure to fleas or another animal that was exposed. However, most cats with the infection show no signs of illness.

Symptoms of cat scratch disease appear within two weeks after the contact with an infected animal. Swelling and redness occur around the wound, and you also may experience a fever, headache, poor appetite and fatigue.

The most notable characteristic of the disease is tender and swollen lymph nodes near the wound that typically remain swollen for months. Although the disease will clear on its own in healthy people, treatment with antibiotics may be recommended. Rarely, the disease can cause serious complications, especially in children under 5 and people with weakened immune systems.

A Mayo Clinic study reported that 1 in 3 people seeking treatment for cat bites on the hand needed to be hospitalized. And most of those hospitalized needed surgery to remove infected tissue. This is because penetration was deep enough to deposit bacteria into the joints or protective layers around the tendons.

There are steps you can take to prevent infection from a cat bite or scratch. Wash your hands after contact with a cat. Don’t roughhouse or provoke a cat, and don’t allow young children to chase or grab your cat. If you are bitten or scratched, wash the area well with soap and running water. If it’s a bite, see your health care provider — even if the wound appears small. And report any bites from a feral or stray cat. Preventive treatment for rabies may be recommended.

If you are a cat owner keep your cat’s claws trimmed and use care when grooming your pet. Make sure your tetanus vaccination, which needs to be updated every 10 years, is current. Keep cats indoors to minimize their exposure to infected animals. Finally, treat your cat with flea prevention medication. — Dr. Christopher Boswell, Family Medicine, Mayo Clinic, Rochester, Minnesota

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