Bartonella henselae is a proteobacterium that is the causative agent of cat-scratch fever (Bartonellosis). As the name suggests, it occurs after a cat bite or scratch. The disease is characterized by lymphadenopathy (swelling of the lymph glands ) and fever.
Bartonella henselae is a member of the class of the Bartonella genus, one of the most common type of bacteria in the world.