Rickettsialpox is an uncommon, mite-borne rickettsial disease caused by the agent Rickettsia akari. R. akari was first isolated in 1946 from a patient, mites, and a naturally infected house mouse in Queens, New York [1]. The disease was named rickettsialpox because of its resemblance to chickenpox. The etiologic agent was named Rickettsia akari because the causative agent belonged to the genus Rickettsia and because akari is Greek for "mite." R. akari is a member of the spotted fever group of rickettsiae of which R. rickettsii is the prototype. (See "Biology of Rickettsia rickettsii infection".)