Lecture 34: Surveillance Flashcards
What is 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
- Ongoing descriptive epidemiology
- Where appropriate monitor “Process” and “outcome”
What is surveillance used for?
- Characterising patterns of disease
- Detecting epidemics
- Further investigation
- Research
- Disease control programmes
- Setting priorities
- Evaluation
Give 6 examples that surveillance can be used for:
- Infectious diseases
- Chronic diseases
- Injury
- Health service uptake
- Vector distribution (mosquitos)
- Environmental hazards
What are the elements of surveillance?
Health event
-> data collection
-> analysis
-> interpretation
-> dissemination
-> action
“Information for action”
Note for anderdingus: diagram on slide 5
What are the two main types of surveillance?
- Indicator-based
Specific selected “indicators” under surveillance.
- Generally specific infectious diseases or cancers.
- Most commonly passive notification by clinician/laboratory.
- Report on rates of disease by demographic characteristics of affected individuals: time, person and place - Event-based
Organised monitoring of reports, media stories, rumours, and other information about health events that could be a serious risk to public health
- Rumour surveillance = media, social media, medical reports, blogs
Name the 3 different types of surveillance within indicator-based surveillance:
Passive surveillance
Active surveillance
Sentinel surveillance
What is passive surveillance and why is it useful?
Routine reporting of health data
- Notifiable diseases e.g. measles, monkeypox: clinicians are required to notify the public health unit
- Disease registries e.g. cancer, chronic diseases
- Hospital data
Useful for:
- Baseline data
- Monitor trends
- Monitor impact
What are the advantages and limitations of passive surveillance?
Advantages:
- Low cost
- Wide area
- Data linkage
Limitations:
- Under-reporting of true prevalence within a population e.g. TB: 50% of cases are not notified to the National TB programme therefore, need to strengthen public-private partnership for TB case detection
What are the 2 types of active surveillance?
- Serosurveillance: The monitoring of the presence or absence of specific substances in the blood serum of a population
- Health survey: Example: Active case finding of TB in Indonesia
What is sentinel surveillance?
Collecting data from a selected institution or group
- Monitor diseases or trends
- Detect outbreaks
e.g. unlinked anonymous HIV prevalence - everyone who comes into sexual health clinic is tested, not just those who come forward to be tested which removes bias
What are the characteristics of a good surveillance system (data collection)?
- Clear case definition (strong predictive value)
- Organised
- Workable/practical/simple
- Uniform
- Continuous
- Timely
- Sensitive
- Acceptable (to the public & key stakeholders)
What is included in an analysis?
- Number of cases
- Descriptive epidemiology in more detail:
Person: Age, sex, ethnicity etc.
Place: Within NZ, comparison to other countries
Time: Change over time
Rates (when possible)
What is included in dissemination?
Spreading information
- To those who need to know: Ministry of Health, District Health Boards/Public Health Units, affected population/ key stakeholder groups
- Periodic reports
- Newsletter
- Special alerts/Media
- Annual report
- Presentations
What is included in “Action”? Use HIV as an example:
A series of goals/action plan towards the issue
e.g. HIV
Goal 1: Reduced number of new locally acquired HIV infections
Goal 2: Improved Māori health and wellbeing in relation to HIV by delivering on our Tiriti o Waitangi obligations
Goal 3: Decreased mortality and the negative consequences of HIV on health and wellbeing
Goal 4: Decreased experiences of stigma and discrimination for people living with HIV
Goal 5: Increased equity in relation to all HIV goals and objectives
