Epidemiology of Infectious Diseases Flashcards
Differentiate between infection and infectious disease
Infection is the invasion of a host by a pathogen
Infectious disease is the illness as a result of the infection
This term describes the ability of an agent to infect and multiply —> disease
Pathogenicity
This term refers to the pathophysiological reaction of the host to the infection
Severity
Can a person be a case and a contact at the same time?
No
A contact is someone who has been exposed but hasn’t been confirmed to have the infectious disease. They must quarantine until they are confirmed to have the disease
A case is someone who is confirmed to have an infectious disease
This is the time between exposure and the appearance of S&S
Incubation period
During what time is a person able to transmit a disease?
The infectious period/period of communicability
Is it necessary for a person to have S&S to be in the infectious period?
No
People are able to transmit a disease even when they aren’t showing any S&S
Malaria is endemic to tropical and subtropical regions, particularly those with the anopheles mosquito. What kind of occurrence does malaria demonstrate?
Endemic
Occurs constantly at a maintained rate within a region — continuous high prevalence
What is the term for a disease demonstrating temporarily high prevalence in a population over a specific time?
Epidemic
This is the spread of an epidemic to global proportions
Pandemic
What are the 3 components of the epidemiological triangle?
Agent
Host
Environment
What part of the epidemiological triangle do pathogens fall into?
Agent: the thing causing the infectious disease
What host factors impact susceptibility of a host to an agent?
Genetics
Age
Health status
Living conditions
What is herd immunity?
Resistance of a population to a particular disease
What determines the herd immunity a population has to a disease?
The amount of pre-existing immunity in a high proportion of ppl r/t previous infection or vaccination
What is a factor that determines the amount of immunity needed in a group of ppl to gain herd immunity?
The pathogen
What are the 2 requirements for herd immunity?
High and variable immunity within a group
Uniform distribution of immunity within a group
What environmental factors can make a host susceptible to an infectious disease?
living conditions
Water/food
Climate
Pollution
Migration
What are the 6 components of the chain of infection?
Agent
Reservoir
Portals of exit
Mode of transmission
Portals of entry
Host
A term used for the habitat in which an infectious agent normally thrives and multiplies
Reservoir
What are the direct modes of transmission?
Direct transmission is the immediate transfer to a portal of entry
Ex droplet, touching, biting, kissing, etc.
What are indirect modes of transmission?
An intermediate is contaminated, interacted with by the host and then leads to infection of the host
airborne
Waterborne
Food borne
Vector borne (carried by another living thing)
Fomites (inanimate materials/objects)
