Flashcards in IDT231 Deck (44):
is the study of the distribution and determinants of health-related states or events in specified population, and the application of this study to control of health problems.
describes the distribution of diseases and health conditions – person, place, time
finds out ‘causes’ or determinants – the three most common types of analytic study are: cohort studies, case-controlled studies and cross-sectional or prevalence studies.
is concerned with the prevention and control of health problems. The investigator controls an exposure of individuals in a population to a suspected factor, exposure randomly allocated to comparable groups, minimize confounding factors and outcome monitored, i.e. antibiotic clinical trial
Experimental (interventional) epidemiology
is the number of new infections divided by the number of those exposed – also known as incidence rate and case rate
the difference between the true value and that established in the study – three types: selection, information, confounding
an individual who harbors a microorganism (agent) without clinical evidence of disease. Carriers may shed organisms into environment intermittently or continuously and shedding may lead to transmission
an individual who is recognized as having the condition of interest based upon the “case definition”.
a grouping of relatively uncommon events or diseases in time and/or space in numbers that are believed to be greater than those numbers expected by chance alone.
the multiplication of a microorganism at a body site or sites without evidence of infection. Colonization may or may not be a precursor for infection. Colonization may be a form of carriage and is a potential source of transmission
the time in the natural history of an infection during which transmission may occur.
an exposed individual who might have been infected through transmission of an infectious agent from another colonized or infected individual.
having the potential for transmission
the presence of an agent on a surface or in a fluid, therefore, a potential source of transmission.
the usual level or presence of an agent/disease in a defined population during a given period
an unusual, higher-than-expected level of disease by an agent in a defined population in a given period – an increase over baseline rates
a graphic representation of the distribution of defined cases by the time of onset of their disease
the time period over which the excess number of cases occurred
the level of an agent or disease which is consistently present at a high incidence and/or prevalence rate
All new cases
resistance of an individual to a specific agent, characterized by measurable and protective antibody or by cell-mediated immune response. Immunity may result from specific previous exposure with the agent. Immunity to some agents remains lifelong whereas for others it is short-lived.
ratio of number of new infections or disease in a defined population to the number of individuals at risk in the population, in a given period of time.
the period between exposure to an agent and the first appearance of evidence of disease in a susceptible person
the first case to be recognized in the series of transmissions of an agent in a susceptible population
the successful transmission of a microorganism to a susceptible person with subsequent colonization, multiplication, and invasion. Infection may be clinically apparent or subclinical (no identifiable disease or symptoms
the physical separation of an infected or colonized individual (including contaminated body fluids and environmental materials) from the remainder of the at-risk population in an attempt to prevent transmission of a specific agent within the at-risk population
all cases of disease including new (incident) and established cases
An animate or inanimate niche in the environment in which an infectious agent may survive and multiply to become the source of transmission to a susceptible individual
changes in measurable events over an extended period of time, also known as temporal trend.
Occurring irregularly or usually infrequently over a period of time
the ongoing systematic collection, analysis and interpretation of health care data essential to the planning, implementation and evaluation of health care practice.
routine reporting of special health events (notifiable diseases) to health authorities by health institutions and practitioners as mandated by law.
resource-intensive, more complete. Involves searching out various sources to solicit information on a regular basis
– A condition of the person that indicates absence of protection against infection by an agent; often absence of specific antibodies.
The method by which any potentially infecting/infectious agent is spread to another person.
touching between people, projection of large droplets in coughing and sneezing before they fall to the ground (usually considered to be within one metre of the mouth).
vehicle-borne, airborne or vector-borne:
water, food, syringes, which may act as an intermediate source of the infectious agent from a reservoir
aerosols containing small (1-5 microns) particles may be suspended in air for long periods and inhaled into the lower respiratory tract.
arthropods or other invertebrates may carry or transmit microorganisms usually through inoculation by biting
If observation period begins as present time and continues into the future or until the appearance of disease