A relatively mild disease in humans transmitted from rats to humans by a rat flea, where the disease organism enters the bloodstream when flea feces are scratched into a flea-bite wound, causes fever, severe headache, and rash. Which disease is this?

A relatively mild disease in humans transmitted from rats to humans by a rat flea, where the disease organism enters the bloodstream when flea feces are scratched into a flea-bite wound, causes fever, severe headache, and rash. Which disease is this?

• A. Plague
• B. Murine typhus fever
• C. Leptospirosis
• D. Ringworm

Answer: (B)

This disease is characterized by a rat-flea transmission cycle where the bacteria are carried in the flea’s feces and enter the person’s bloodstream when those feces are scratched into a bite wound. That mechanism, along with fever, severe headache, and a spreading rash, points to murine typhus caused by Rickettsia typhi. It’s described as relatively mild compared to other flea-borne illnesses like plague, which can cause severe illness with buboes and more dramatic symptoms. Leptospirosis involves contact with urine-contaminated water and isn’t transmitted by flea feces, and ringworm is a fungal skin infection, not a systemic febrile disease.

This disease is characterized by a rat-flea transmission cycle where the bacteria are carried in the flea’s feces and enter the person’s bloodstream when those feces are scratched into a bite wound. That mechanism, along with fever, severe headache, and a spreading rash, points to murine typhus caused by Rickettsia typhi. It’s described as relatively mild compared to other flea-borne illnesses like plague, which can cause severe illness with buboes and more dramatic symptoms. Leptospirosis involves contact with urine-contaminated water and isn’t transmitted by flea feces, and ringworm is a fungal skin infection, not a systemic febrile disease.