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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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The usual incubation period of peusis is ?
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The correct answer is  Ans. is 'a' i.e., 7-14 days Whooping cough (peussis) After an incubation period of about 1-2 weeks, the disease takes a protracted course comprising three stages-- the catarrhal, paroxysmal and convalescent - each lasting approximately two weeks.