Abstract
(1) Background: Murine typhus, caused by Rickettsia typhi, is a neglected rickettsial disease and an underdiagnosed cause of acute febrile illness (AFI), particularly in endemic regions such as Indonesia. (2) Case description: We report a case series of four patients presenting with AFI of less than seven days in duration. Three patients were admitted with moderate disease, while one presented with septic shock with the macrophage activation-like syndrome (MALS) phenotype. Common clinical features included myalgia and headache; additional symptoms included cough, sore throat, and abdominal pain. Laboratory findings revealed bicytopenia, elevated transaminases, and raised inflammatory and bacterial infection markers. Common tropical infections-dengue, typhoid fever, and leptospirosis-and other potential sources of infection were excluded early during hospitalization. Diagnosis was confirmed by nucleic acid amplification testing (NAAT), which detected R. typhi in all patients. Doxycycline was initiated following confirmation, leading to defervescence within 36-48 h. (3) Conclusions: Murine typhus remains an underrecognized cause of febrile illness in Indonesia. In the near future, the inclusion of rickettsial testing in the diagnostic protocol of AFI will be crucial, as it enables timely administration of effective, low-cost treatment.