Cat Scratch Disease
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
Cat scratch disease (CSD) is an illness caused by the bacterium Bartonella henselae. Almost half of all cats carry the infection at some point. The infection does not make cats sick. However, the scratch or bite of an infected cat can cause symptoms in people, including :
- Swollen lymph nodes, especially around the head, neck, and upper limbs
- Fever
- Headache
- Fatigue
- Poor appetite
For people with weak immune systems, CSD may cause more serious problems. The best way to avoid CSD is to avoid rough play with cats that could lead to scratches or bites. If you do get a scratch or bite, wash it well with soap and water. If the bite or scratch gets infected or if you have symptoms of CSD, call your doctor.
Centers for Disease Control and Prevention
Questions for your care team
General prompts to help prepare for your appointment.
- How does this information apply to my situation?
- Which symptoms or results need evaluation?
- Which tests are useful, and what can they tell us?
- What care options, benefits, and risks should we discuss?
- When should I seek urgent help, and whom should I call?
- When is follow-up, and how will we know whether the plan is working?
For a life-threatening emergency, call 911 in the U.S. or your local emergency number.
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