Secondary attack rate is a measure of-: (A) communicability, (B) Lethality, (C) Strength of association, (D) None
Answer is A. Secondary attack rate is defined as the number of exposed persons developing the disease within the range of incubation period. It was initially developed to measure the spread of an infection within a family, household or any closed aggregate of persons who have had contact with a case of disease (refer pgno:100 park 23 rd edition)