Volume 11, Number 9—September 2005
Genus of gram-negative, rod-shaped or coccoid bacteria that are transmitted by lice, fleas, ticks and mites. Named after American pathologist Howard Taylor Ricketts; despite the similar name, Rickettsia spp. do not cause rickets (from the Greek rhakhis, “spine”), a disorder of bone development caused by vitamin deficiency.
Source: Dorland’s illustrated medical dictionary.30th ed. Philadelphia: Saunders, 2003.