This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable diseases, Subject name: Social & Preventive Medicine
[{'content': 'Endemic typhus cause and vector is \nSelect and explain. \nA. R. prowazki and louse, B. R. typhi and Rats, C. R. conori and tick, D. R. akari and mite', 'role': 'user'}, {'content': "Answer: B \nExplanation: Endemic Typhus Is also known as 'Flea borne typhus' or 'Murine Typhus' Causative agent : Rickettsia typhi (R.mooseri) Reservoir: Rats Mode of Transmission : Rat Flea (Xenopsylla cheopsis) - But not Through bite, rather through feces innoculation on skin or inhalation of dried infective faeces Incubation period : 1-2 weeks Weil-Felix reaction: Becomes positive with proteus OX-19 in 2nd week Drug of choice : Tetracycline Ref: Park 25th edition Pgno : 316", 'role': 'assistant'}]