Unit 11 Flashcards
illness
subjective state of the person who feels aware of not being well
disease
physiological or psychological dysfunction
sickness
state of social dysfunction
cause of disease
a factor that influences the occurrence of disease
etiology
cause or origin; all of the causes of disease or abnormal condition
What is the Germ Theory?
The idea posed by Pasteur and Koch that specific diseases are caused by specific organisms.
What are Henle-Koch’s postulates?
An explanation of the causative involvement of a microorganism in the pathogenesis of an infectious disease.
Describe the epidemiological triad.
It’s the traditional model of infectious disease, which includes: an agent, a susceptible host, and the environment. The environment influences the route of transmission of the agent from a source to the host.
Name a few types of agents.
In reference to an infectious microorganism: bacteria, viruses, fungi, parasites, prions. (Necessary, but not always sufficient)
In reference to noninfectious diseases: physical (noise), chemical (solids, liquids, gases), psychological (stress), social (school), and economical (job).
What are host factors?
Includes intrinsic and extrinsic factors which influence exposure to agent.
Also includes intrinsic factors affecting susceptibility to an agent.
What is the purpose of epidemiological model?
It helps to find practical and effective prevention and control measures to fighting disease.
What was the first recorded epidemic?
Smallpox in 1350 B.C.
Name some emerging infectious diseases in the USA
E. coli, the flu, and pneumonia
Name some emerging infectious diseases around the world.
Cholera, Yellow Fever, E. coli, Dengue, Shingles
Why do diseases reemerge?
societal events (war, population growth); health care (transplants); food production (changes in food processing); human behavior (sex, drugs, travel); environmental changes (deforestation, floods); pubic health infrastructure (reduction in prevention programs); microbial adaptation (development of drug resistance)
When does transmission occur?
1) when agent leaves its reservoir or host
2) through a portal of exit
3) enters through a portal of entry to infect susceptible host
What is a reservoir?
A habitat in which an infectious agent normally lives, grows, and multiplies; can be humans, animals, and environment
What are a few types of transmission?
Direct: person-to-person; droplet
Indirect: airborne, common vehicle, vector-borne
Name a few portals of entry.
Skin, mucous membranes, and systemic
(agent needs host, such as a tissue, on which to grow and multiply
Define herd immunity.
The resistance of a group or population to the spread of a disease due to the fact that a high proportion of the group or population is immune to the disease
What are the three levels of usual prevalence?
1) endemic level
2) hyperendemic level
3) sporadic level
What is an outbreak of disease?
An epidemic limited to a localized increase in the incidence of a disease
Why do outbreaks occur?
1) Increase in amount of agent
2) Recent introduction of agent into a new setting
3) Enhanced mode of transmission
4) Factors that increase host exposure
What is the purpose of a disease outbreak investigation?
To identify the cause of the disease as to prevent spread of the disease
