Massachusetts General Hospital

Cat Scratch Disease

What is cat scratch disease?

Cat scratches and bites can cause cat scratch disease, a bacterial infection carried in cat saliva. The bacteria are passed from a cat to a human after the cat licks its paws then scratches human skin. Rubbing the eyes after petting a cat's fur can also spread cat scratch disease. Young kittens younger than one year of age are more likely to scratch, increasing the likelihood of infection.

What are the symptoms of cat scratch disease?

The following are the most common symptoms of cat scratch disease. However, each individual may experience symptoms differently. Symptoms may include:

• A cat bite or scratch that becomes reddened or swollen within a few days and does not heal or worsens over time

• Painful or swollen glands, especially under the arms (if scratched on the arm or hand), or in the groin (if scratched on the foot or leg) 

• Flu-like symptoms including headache, lethargy, decreased appetite, fatigue, joint pain, or fever

• Body rash

The symptoms of cat scratch disease may resemble other conditions or medical problems. Always consult your doctor for a diagnosis.

Treatment for cat scratch disease

Specific treatment for cat scratch disease will be determined by your doctor based on the following:

• Your age, overall health, and medical history

• Extent of the injury

• Location of the injury

• Your tolerance for specific medications, procedures, or therapies

• Expectations for the course of the injury

• Your opinion or preference

Treatment may include:

• Antibiotics (to treat the infection)

• Supportive care (to treat the symptoms that result from the infection). In many cases, no antibiotics are needed, and the infection will clear on its own.