N R I G B.C
Chapter 02: The Dynamics of Disease Transmission
Celentano: Gordis Epidemiology, 6th Edition
Test Bank
MULTIPLE CHOICE
1. Which term most
... [Show More] accurately describes the following definition? “The occurrence in a
community or region of cases of an illness, specific health-related behavior, or other health
related events clearly in excess of normal expectancy.” [Porta M, ed. A Dictionary of
Epidemiology. New York: Oxford University Press; 2014.]
a. Endemic
b. Epidemic
c. Pandemic
d. Attack rate
e. Incubation period
ANS: B
An epidemic is the occurrence of health-related events in a community or region, in clear
excess of normal expectation. Endemic is not true because it is defined as the constant
occurrence of a disease, disorder, or noxious infectious agent in a geographic area or
population group. Pandemic is not true because it is defined as an epidemic occurring over a
very wide area, crossing internationUal bSounNdarTies, andOusually affecting a large number of
people. Attack rate is not true because it is defined as number of people at risk in whom a
certain illness develops over total number of people at risk. Incubation period is not true
because it is the interval from receipt of infection to the time of onset of clinical illness (the
onset of recognizable symptoms).
2. What is the most accurate definition of the incubation period (of an infectious disease)?
a. The time of onset of clinical illness or the onset of recognizable symptoms
b. The interval from receipt of infection to the time of onset of clinical illness (the onset of
recognizable symptoms)
c. The time of invasion by an infectious agent
d. The time between initiation of infection and first shedding or excretion of the agent
e. The period between exposure and the onset of infectiousness
ANS: B
The incubation period is defined as the interval from receipt of infection to the time of onset
of clinical illness (the onset of recognizable symptoms); in other words, the time between the
moment of developing symptoms and the moment of invasion by an infectious agent. “The
time of onset of clinical illness or the onset of recognizable symptoms” is not true as it
corresponds to “time of onset.” “The time of invasion by an infectious agent” is not true as it
corresponds to “time of infection.” “The time between initiation of infection and first
shedding or excretion of the agent” and “The period between exposure and the onset of
infectiousness” are not true as they correspond to the latent period. (The latent period is [Show Less]