Lectures 3-7 Flashcards
Surveillance systems
- Passive Surveillance - relies on healthcare system to follow regulations on required reportable disease/conditions (passively wait for reports to come in) - Active Surveillance - public health officials go into communities to search for new disease/condition cases - Syndromic Surveillance (acute and severe) - a system that looks for pre-defined signs/symptoms of patients related to trackable-but-rare diseases/conditions
Induction
Time between exposure and onset of disease
Latency
Time between onset of disease and disease detection (symptoms or diagnosis)
Case definition
- A set of uniform criteria used to define disease/condition for public health surveillance - Enable public health to classify and count cases consistently by reporting across jurisdictions
Epidemic
- Occurrence of disease clearly in excess of normal expectancy - community/period clearly defined - goal is to capture disease as early as possible
Outbreak (cluster)
- An epidemic limited to a localized increase in the occurrence of disease
Endemic
- Constance presence of a disease within a given area or population in excess of normal levels in other areas
Emergency of international concern
- An epidemic that alerts the world to the need for high vigilance (pre-pandemic)
Pandemic
- An epidemic spread world-wide (global health) - multinational/multi-continent
Epidemic curve
- A visual time-based description created during an outbreak/epidemic # of cases by date of reporting (Look at slides)
3 key factors in comparing measures of disease freq. between groups
- # of people affected/impacted (frequency/count) - Size of the source population or those at risk - Length of time the population is followed (pop. size and time period of evaluation must be equal to adequately and appropriately compare between groups)
Incidence
of new cases of illness/# of people at RISK for illness
Incidence rate
of new cases of illness/person-time at risk for disease
Incidence density
of new cases/total person-time of pop. at risk
Prevalence
of existing cases of a disease/# of persons in pop.
Point prevalence
- Prevalence at a given point in time (ex. Dec 31st)
Period prevalence
- Prevalence over a given period of time (during 2012)
Infectivity
- Ability to invade host # infected/# at risk (exposed)
Pathogenicity
- Ability to cause clinical disease # clinical disease/# infected
Virulence
- Ability to cause death # of dead/# of infected
What type of Outbreak does this Graph show?
Intermittent Outbreak/Common/Point Source
What type of Outbreak does this graph show?
Common/Point Source
What type of Outbreak Does this Graph Show?
Propagated (Person-to-Person Transmission)
