Cat scratch disease is an infectious illness caused by the bacteria bartonella (Bartonella henselae). It is believed to be transmitted by cat scratches, bites, or exposure to cat saliva. This self-limiting infectious diseaseis characterized by a bump or blister at the site of the bite or scratch and swelling and pain in the lymph nodes. Other features may include fatigue, headache, achiness, and fever. Although cat-scratch disease usually subsides without treatment, antibiotic and/or antimicrobial therapy may help speed recovery.