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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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Commonest age group for diptheria is -
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The correct answer is  Diphtheria paicularly affects children aged 1 to 5 yrs. In countries where widespread immunization practised, a shift in age incidence has been observed from preschool to school age. Ref:PARK&;S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICINE 23rd edition , Page :160