Which of the following illnesses is caused by Rickettsia typhi?

Rickettsia typhi is the bacterial agent responsible for murine typhus, which is primarily transmitted through flea bites, specifically from the fleas that infest rats. This illness typically presents with symptoms like fever, headaches, and rash, aligning with the characteristics associated with murine typhus.

In contrast, the other options represent different diseases caused by other pathogens. Plague is caused by Yersinia pestis, Lyme disease is caused by Borrelia burgdorferi, and Rocky Mountain spotted fever is caused by Rickettsia rickettsii. Therefore, recognizing the specific bacteria responsible for murine typhus and understanding its transmission dynamics is crucial for identifying the correct answer. This contextual knowledge is vital for effective vector control and public health interventions.