print   Print full article

What are Rickettsial diseases?

Rickettsial diseases are caused by bacteria called Rickettsia or Orientia. These are small bacteria that reside inside infected cells. A host insect, such as a tick or flea, is where the bacteria reside for much of their lifespan. A bite from this insect is required to spread the Rickettsia bacteria to a human. In Southern and Eastern Australia, the most important Rickettsial infections include Queensland tick typhus and Flinders Island spotted fever, which are spread by ticks. In Northern Australia, the rickettsial infections scrub typhus and murine typhus are spread by rodent fleas. Other types of Rickettsial infections can be acquired from overseas travel, but the bite of the carrier insect is required. For this reason it is important to tell your doctor where you have travelled and if you remember being bitten by an insect if you have signs and symptoms of a Rickettsial infection. Overall, Rickettsial infections are uncommon in Australia so this diagnosis is often overlooked, as the signs and symptoms overlap with many other types of illnesses.


Last Review Date: August 8, 2017