Unit 1 Principles of Epidemiology Flashcards
A primary, or definitive, host is one in which a disease organism
attains its maturity and goes through its sexual or reproductive stage
A secondary, or intermediate, host is one in which a disease organism
enters the larval stage
A person or other living animal, including birds and arthropods, which are harboring a disease agent
host
The person or animal that harbors a disease agent, but has no clinical signs of the disease is
carrier
Are organisms that live on or in the body of a host and can produce disease or illness
Agent
In a host-agent relationship, the ability of an agent to produce clinical disease in a host is its
pathogenicity
In a host-agent relationship, the ability of an agent to invade and multiply, or to produce infection, in a host is its
infectivity
The proportion of clinical cases resulting in severe clinical manifestations
virulence
In a host-agent relationship, all of the following are types of agents except
a. fungi.
b. metazoa.
c. virulence.
d. rickettsia.
c. virulence
Are multicellular organisms, often referred to as parasites
Metazoa
Are single-celled, animal-like organisms. Most are free-living and found in soil and water
Protozoa
Are microscopic, single-celled organisms
Bacteria
What different shapes can bacteria appear in
bacillus (rod)
coccus (sphere)
spirillum (spiral)
Are small bacteria. Most are obligate, intracellular parasites; that is, they must live within living cells
Rickettsia
Are particles of nucleic acid
surrounded by a protein sheath; they are highly infectious
Viruses
How can agents enter the body?
Ingestion
Inhalation
Penetration
Diseases such as rabies are spread using this type of direct transmission mode
Direct contact
Identify the three-link chain
Source
Mode
Host
This is not a general health status factor for determining disease occurrence
a. Preexisting disease.
b. Physiological state.
c. Behavioral factors.
d. Nutritional status.
c. Behavioral factors
In countries where pork is eaten, individuals may be at risk of trichinosis infection when the
pork is undercooked. Which intrinsic disease occurrence factor is this an example of?
Diet
Using what is called night soil as a fertilizer allows the transmission of such diseases as typhoid, dysentery, amebiasis, and hepatitis. Preventing the transmission of these diseases
involves
proper human waste disposal
Is one of the most important factors in the control of communicable disease
personal hygiene
This environmental factor has the greatest effect on hay fever sufferers
Climate
Which environmental factor is a medicinal source, such as Quinine that comes from tree bark and is used to treat malaria?
Biological
Which factor contributes to the emergence of new infectious disease or the reemergence of old diseases?
Societal disruptions
Which term is used to define numeric facts or data that have been assembled, classified, and
tabulated to present significant information about a given subject?
Statistics
Which statistical term is most commonly used as a measurement of central tendency?
Mean
Which statistical term is characterized by the number occurring most often in a group or set of numbers
Mode
Using statistics, the mode for numbers 6, 18, 26, 14, 12, 19, 20, and 26 is
26
Which statistical term is characterized by arranging the data from the smallest number to the largest number
Median
Using statistics, the median of the numbers 3, 3, 5, 7, 8, 9, and 12 is
7
Public health uses rates as one of its most important statistical tools. What does the noneffectiveness rate tell you about individuals’ illnesses or injuries?
Temporary loss from duty
This statistical rate is used to determine the probability of new disease cases affecting
healthy people during a given time
Incidence rate
If 30 out of 90 people who ate at a base picnic became ill, the attack rate per 100 persons is
33.30
A method that is used to study two similar groups by administering a vaccine, special diet, or some other factor to one group while withholding it from the other group is called
experimental
This method is used to study different groups under natural conditions
Observational
Which disease study method traces the source of a food poisoning outbreak or examines sexually transmitted infection (STI) incidence and prevalence?
Uncontrolled observation.
This is simply observing, questioning, and studying a population at one point in time in order to detect cases of a disease
Cross-sectional survey
In this design, you study persons who already have the disease; you also study people who are free of the
disease
Retrospective
This is a plan of study in which a group under observation is divided into two groups; one having a
factor believed to contribute to a disease and the other without the factor
Prospective
In this step of an outbreak investigation, it is important for you to know what disease to look for and you must separate cases from noncases
Establish or verify the diagnosis
In this step of an outbreak investigation, compare the current incidence and the usual, or expected,
incidence
Establish existence of an outbreak
