Lecture 32: Epidemiological Surveillance Flashcards
Define epidemiological surveillance
Ongoing systematic collection, analysis, interpretation and dissemination of data regarding a health event for use in public health action to reduce morbidity and mortality and to improve health
Epidemiology is the ongoing _______ epidemiology which means
ongoing
understanding the ongoing story and how to influence it
Surveillance is relevant to what six things?
- infectious diseases
- chronic diseases
- injury
- health service uptake
- vector distribution
- environmental hazards
What are the six elements of surveillance?
- health event occurs
- data collection
- analysis
- interpretation
- dissemination
- action
Define disemmination
the action or fact of spreading something, especially information, widely.
What is surveillance used for? (7)
- characterising patterns of disease
- detecting epidemics
- further investigation
- research
- disease control programmes
- setting priorities
- evaluation
What are some patterns of disease, and what do these patterns mean?
time: when is the disease occurring (eg. what month or time of year)
place: where is it (eg. in a particular geographic location)
population: who are the main people effected (eg. any particular ethnic groups)
What are the two types of surveillance?
indicator based and event based
Indicator based surveillance is usually based around what diseases?
infectious diseases of cancers
What is being looked at in indicator-based surveillance?
specific selected indicators
What is event based surveillance?
organised monitoring of reports, media stories, rumours, and other information about health events that could be a serious risk to public health
What does indicator based surveillance involve?
Indicator-based surveillance involves reports of specific diseases from health care providers to public health officials.
What are the three types of indicator based surveillance?
passive
active
sentinel
What is passive surveillance? Give two examples
Routine reporting of health data of notifiable diseases as they present.
Examples include disease registries (eg. cancer and chronic diseases) and hospital data
What does passive surveillance useful for?
it is a useful source of health information that means we have baseline data, we can monitor trends and we can monitor impact.
What are three advantages to passive surveillance?
low cost
they span a wide area
they link data
What is a limitation of passive surveillance?
there is risk of under reporting the presentation of diseases
What is active surveillance? Give two examples
When you are actively seeking out diseases within a population
examples are serosurveillance (monitoring the presence of absence of specific substances in the blood serum of a population) and a health survey
What is sentinel surveillance? What does this allow us to do?
Selected institutions of groups are given a signal about what might be happening in a certain population which allows us to monitor diseases or trends and detect outbreaks
What are 8 characteristics of a good surveillance system within the data collection aspect?
- clear case definition
- organised
- workable/practical/simple
- uniform
- continuous
- timely
- sensitive
- acceptable to the public and key stakeholders
What does the analysis need to tell us?
- number of cases
- descriptive epidemiology in more detail:
- person (age, sex, ethnicity)
- place (within NZ, comparison to other countries)
- time (change over time)
- rates (when possible)
What is the question asked in the interpretation?
What is going on?
What is involved in dissemination? Who needs to know?
- People need to know: Ministry of Health, DHB, the affected population
- periodic reports
- newsletters
- media
- annual reports
- presentations
What is a big problem with global surveillance?
There is always more cases than what is reported
