Cat scratch disease
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
- Poor appetite
Most people do not require treatment for the disease; however, for people with weak immune systems, CSD may cause more serious problems and might require antibiotics. The best way to avoid CSD is to avoid rough play with cats that could lead to scratches or bites.