Rickettsioses can be divided into a
spotted fever group (SPG) and
typhus group (TG). In the past, rickettsioses were considered to be caused by species of
Rickettsia. However,
scrub typhus is still considered a rickettsiosis, even though the causative organism has been reclassified from
Rickettsia tsutsugamushi to
Orientia tsutsugamushi. Examples of rickettsioses include
typhus, both endemic and epidemic,
Rocky Mountain spotted fever, and
Rickettsialpox. Organisms involved include
Rickettsia parkeri. Many new causative organisms have been identified in the last few decades. Most are in the genus
Rickettsia, but
scrub typhus is in the genus
Orientia. ==Diagnosis==