There are two families of bacteria that cause rickettsioses: Rickettsiaceae (Rickettsia and Orientia) and Anaplasmataceae (Anaplasma, Neorickettsia, and Ehrlichia).
Ehrlichioses and Anaplasmoses are tick-borne diseases caused by small, intracellular bacteria belonging to the Rickettsiaceae family and originally belonging to the Ehrlichia genus.
Scrub typhus, a widely endemic disease in Asian Pacific regions, is caused by Orientia tsutsugamushi, a gram-negative obligate intracellular bacterium in the family Rickettsiaceae
family comprises obligate intracellular bacteria and contains 2 genera: Rickettsia (typhus group and spotted fever group[SFG]) and Orientia.
quintana was classified in the genus Rochalimaea, tribe Rickettsiae, family Rickettsiaceae
The fallout from the reclassification of these organisms is the proposal for a complete revision of the families Rickettsiaceae
Other known pathogenic bacteria transmitted by ticks are intracellular alpha proteobacteria, which includes the families Anaplasmataceae, Bartonellaceae, and Rickettsiaceae