Interval between primary and secondary case is called as:-: (A) Serial interval, (B) Generation time, (C) Incubation period, (D) Lead time
Answer is A. The gap in time between the onset of the primary case and the secondary case is called "serial interval". Incubation period: The time interval between invasion by an infectious agent and appearance of the first sign or symptom of the disease in question. Generation time: interval of time between the receipt of infection by a host and maximal infectivity of that host Lead time: it is the advantage gained by screening, i.e. the period between diagnosis by early detection and diagnosis by other means.