17th June 2024

Rickettsial infection

Rickettsial disease refers to infection caused by intracellular bacteria of the family Rickettsiaceae. All these diseases present with a typical triad of fever, arthralgia, and rash. Louse-borne – epidemic – typhus occurs when Rickettsia prowazekii is transmitted through the infected faeces of the human body louse via the skin. It is associated with areas of poor hygiene, such as refugee camps, and can cause multi-organ inflammation and failure, with a high mortality rate if left untreated. Tick typhus, including Rocky Mountain spotted fever and African tick typhus, have varying clinical courses. There is usually an eschar present with African tick typhus, and it is generally less severe than Rocky Mountain spotted fever. Finally, scrub typhus, caused by Orientia tsutsugamushi, is transmitted via biting mites from Eastern Asia and Oceania. A small eschar can be found at the site of the bite, with hepatosplenomegaly and multi-organ dysfunction possible sequalae. Rickettsial disease is generally susceptible to tetracycline antibiotics.