Cat scratch is an illness that can occur after contact with cats, most commonly kittens. More than a hundred years ago, a French eye doctor recorded the first case of bartonellosis, or what we now call cat scratch disease. He associated it with animals, but not with cats. In 1931, two other French doctors made the link to cats after they examined a 10-year-old patient with unusual symptoms and whose side was covered with cat scratches. Still, it was not until 1992 that doctors learned that cat scratch disease is caused specifically by the Bartonella henselae bacteria carried by cats.
Cat scratch disease is most common in children under age 10. In almost all cases of cat scratch disease, the person who develops it will have had contact with a cat or kitten. The illness is more common in the fall and winter and is not contagious to other humans.
Cats, and especially kittens, become infected with the cat scratch bacteria from fleas. Fleas probably do not spread the bacteria to humans. Rather, cats spread the bacteria to humans through scratching, licking, or biting. Cats that are carrying the bacteria don't get sick and don't need to be treated. (Cat scratch disease should not be confused with toxoplasmosis, which is a more serious disease, especially for pregnant women. Toxoplasmosis can be spread from cat feces in litter boxes.)
To prevent cat scratch disease, keep your cat free of fleas and tell your children to avoid stray cats. Children should be told not to play roughly with any cats or kittens and to stop petting them if they see "airplane ears"–flattened ears on a cat are often a warning sign that they want to be left alone. It's also a good idea to have children wash their hands after playing with a cat. Unless your child has another illness that weakens his or her immune defense system, these precautions should be enough to keep your child safe.
Cat scratch disease is rarely serious and usually goes away on its own. Once your child has had cat scratch disease, he or she is unlikely to get it again. Also, children cannot spread the disease to other children.
Most children who get cat scratch disease can recall being around cats, but they rarely recall being scratched or bitten. Here are some common signs and symptoms of the disease:
A blister or bump may develop on the skin of your child's arm, leg, or head several days after a cat scratch or bite.
A few weeks after the scratch or bite, a swollen gland, called a swollen lymph node, may develop in your child's elbow, armpit, groin, or neck area, near the location of the injury.
The lymph node may be about one to two inches wide, and the skin over it may feel warm and look red.
Your child may also have mild fever, loss of appetite, headache, rash, or tiredness.
In rare cases, more severe symptoms, such as eye infection, drainage of pus from a lymph node, high fever, or infection of the liver, spleen, lungs, or nervous system can occur, but even these symptoms usually clear up without serious damage.
Your child's doctor may make a diagnosis of cat scratch disease by checking for signs and symptoms and finding out about recent contact with a cat or kitten. If in doubt, a blood test can be done to look for a reaction to the infection by your child's immune system. This reaction usually shows up in the first two months after an infection. In some cases a sample from a lymph node may be looked at under a microscope to help make the diagnosis.
Treatment of cat scratch disease may include:
Watching and waiting. In most cases skin signs will go away within three weeks, and lymph node swelling will go away within four months.
Medications for fever or headache. Acetaminophen (Tylenol) or ibuprofen (Advil) may be given. Do not give a child or teen aspirin because its use in children has been linked to Reye's syndrome, a rare but potentially life-threatening condition.
Antibiotics. In more severe cases antibiotics such as azithromycin, doxycycline, and rifampin may be given to reduce signs and symptoms.
Surgery. If a lymph node becomes large, painful, or badly infected, surgery may be done to drain the node or remove it.
If your child gets bitten or scratched by a cat, make sure to wash the area thoroughly with soap and water. If you see any signs or symptoms of cat scratch disease after contact with a cat, always let your doctor know. If your child is diagnosed with cat scratch disease, let your doctor know if symptoms get worse or don't improve.