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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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Prozone phenomenon is due to -
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The correct answer is  In an agglutination or precipitation reaction, the zone of relatively high antibody concentrations within which no reaction occurs. As the antibody concentration is lowered below the prozone, the reaction occurs. This phenomenon may be due simply to antibody excess or it may be due to blocking antibody or to nonspecific inhibitors in serum. Ref: Ananthanarayan & Parker's textbook of microbiology 9th edition pg:105