Cat scratch fever or cat scratch disease is a relatively rare illness caused by bacteria that cats may carry. The bacteria, Bartonella henselae, is carried by about 40% of cats at some point in their lifetimes, and is transmitted to humans through the scratch or bite of an infected cat, hence its name. It is not known whether a fleabite from an infected cat could transmit the disease, but it is known that kittens are more likely to transmit the disease than are adult cats.
Most people who get cat scratch fever will have an uncomplicated illness that resolves on its own in a few weeks. Symptoms include swelling of the lymph nodes, redness or swelling at the site of the scratch or bite, fever, general achiness, and feeling tired. Generally, an uncomplicated case is not treated because often it is not reported and may be mistaken for the flu.
However, some people run a higher risk of complications from cat scratch fever. Very young children and those with compromised immune systems from autoimmune diseases like HIV or lupus may have complications. These include significant and persistent swelling of the lymph nodes, very high fever, encephalitis, and swollen lymph nodes near an eye, which causes pinkeye-like symptoms. In rare cases the complications — especially from encephalitis — may lead to convulsions.
One should always wash a bite or scratch from a cat with warm soapy water as this may prevent getting any animal borne illnesses. Further, one should watch the scratch or bite over the next few days. If it becomes swollen, turns red or has pus, a medical professional should examine it. If you note the symptoms listed above, you should also contact a doctor.
It has until recently been quite difficult to test for cat scratch fever. Naturally if a person remembers being scratched and can show an infected scratch, this diagnosis is often deduced. Since physicians now have identified the bacteria that causes the disease, blood tests, or in severe cases, a small tissue extraction from a swollen lymph node can correctly identify the presence of Bartonella henselae.
Patients who begin to show more significant reactions to the bacteria may be treated with antibiotics. People with suppressed immune systems are generally routinely given antibiotics to prevent severe complications. Many recover from the illness with no need for treatment beyond a few days rest.
An interesting new theory regarding cat scratch fever is that it may be responsible for many of the cases of chronic swollen lymph nodes in children. Long after a child has fought off the bacteria, he or she may still have swollen lymph nodes, which can be painful. Often antibiotics help to reduce this swelling.