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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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All are true about Antigen drift except -
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The correct answer is  Antigenic drift the gradual sequential change in antigenic structure occuring regularly at frequent intervals. Antigenic drift is due to mutation and selection .It accounts for the periodic epidemics of influenza. REF:ANANTHANARAYAN AND PANIKER'S TEXTBOOK OF MICROBIOLOGY 9TH EDITION PAGE NO-499