Dynamics of Disease Transmission MCQs

Explanation: A single exposure point source epidemic occurs when a group of people are exposed to an infectious agent simultaneously (e.g., contaminated food, water). The outbreak shows a sudden, explosive rise in cases, followed by a rapid decline once the exposure ends. (Option D ruled out) The epidemic curve typically displays a sharp single peak , corresponding to a single incubation period. (Options A & B ruled out)

An area is declared free of epidemic till no new cases are reported for twice the Incubation period of disease from last case Reference: Park's Preventive and social medicine, 27th edition, Chapter Principles of Epidemiology & Epidemiology methods.

Migration studies is the academic study of human migration. Its a method of understanding the relative importance of inherited genetics and environmental factor in medical conditions whose incidence varies around the world Reference: Park's Preventive and social medicine, 27th edition, Chapter Principles of Epidemiology & Epidemiology methods.

Incubation periodis defined as "the time interval between invasion by an infectious agent and appearance of the first sign or symptom of the disease in question" Generation time It is defined as "the interval of time between receipt of infection by a host and maximal infectivity of that host" The gap in time between the onset of the primary case and the secondary case is called the "serial interval SECONDARY ATTACK RATE - No: of exposed susceptible persons developing the disease within range of IP following exposure to primary case Reference: Park's Preventive and social medicine, 27th edition, Chapter Principles of Epidemiology & Epidemiology methods.