are spiral-shaped bacteria that are closely related to bacteria that cause tick-borne relapsing fever (TBRF). They are more distantly related to the bacteria that cause Lyme Disease. First identified in 1995 in ticks from Japan, the bacteria have since been detected in two species of North American ticks, the black-legged or “deer” tick (Ixodes scapularis) and the western black-legged tick (Ixodes pacificus). These ticks are already known to transmit several diseases, including Lyme disease, anaplasmosis, and babesiosis.