The Bartonella henselae bacterium is responsible for the signs and symptoms of Cat Scratch Fever, also known as Cat Scratch Disease (CSD). Carried by otherwise-healthy cats, a bite or a scratch can transmit the disease to a human. Cat scratch fever commonly spreads from one cat to another through fleabites although the Centers for Disease Control (CDC) report that there is no evidence of a fleabite transmitting the disease directly to a human.
The first symptom of cat scratch fever, appearing as soon as three days after the bite or scratch, may include a crusty papule that forms at the site of the wound. The patient's lymph nodes may become swollen and sore to the touch approximately two weeks after the incident. Other symptoms include a low-grade fever, a headache and lethargy.
Some patients may develop complications, especially if they have an immune deficiency, such as HIV and AIDS. These symptoms may include an irreversible inflammation of the eye retina (retinitis) or an inflammation of the brain (encephalitis). In rare cases, the patient may experience convulsions.
Children are more likely than adults to develop cat scratch fever, especially if the child plays roughly with a cat or kitten. Cats that go outdoors are at an increased risk of being bitten by a flea that carries the Bartonella henselae bacteria. Children should not play with stray cats and all scratches or bites should be promptly washed with soap and water.
Along with observation of the symptoms, a doctor may order a test to confirm the presence of anti-bodies to the disease in the patient's blood. The doctor may drain fluid from swollen lymph nodes to alleviate severe pain but a heating pad may offer welcome relief for most cases of lymph node tenderness.
In most cases, the symptoms of cat scratch fever will disappear without medical treatment within three weeks. Swollen lymph nodes may take up to six months to return to normal size. In the rare patient who develops an eye disorder, some damage may be permanent.