An eschar (; Greek: eschara) is a slough or piece of dead tissue that is cast off from the surface of the skin, particularly after a burn injury, but also seen in gangrene, ulcer, fungal infections, necrotizing spider bite wounds, spotted fevers and exposure to cutaneous anthrax. The term "eschar" is not interchangeable with "scab." An eschar contains necrotic tissue, whereas a scab is composed of dried blood and exudate. Black eschars are most commonly attributed to anthrax, which may be contracted through herd animal exposure, but can also be obtained from Pasteurella multocida exposure in cats and rabbits. A newly identified human rickettsial infection, R. parkeri rickettsiosis, can be differentiated from Rocky Mountain spotted fever by the presence of an eschar at the site of inoculation. Eschar is sometimes called a black wound because the wound is covered with thick, dry, black necrotic tissue.