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What is Communicability of disease is assessed by? and explain in detail?
Secondary attack is defined as the number of exposed persons developing the disease within the range of incubation period following exposure to primary case. It is useful in detecting whether a disease of unknown etiology is communicable or not and in evaluating the effectiveness of control measures such as isolation and immunization. Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 108