introduction

1. Surveillance
Public health

2. Public Health Surveillance
“ The ongoing systematic collection, analysis, and interpretation of health data
essential to the planning, implementation, and evaluation of public health
practice, closely integrated with the timely dissemination of these data to
those who need to know.” -CDC
Action
-Planning,
- Implementation &
-Evaluation
Information
-Collection
-Analysis
-Interpretation
- Dissemination

3. Methodology of Surveillance
2. Active
Surveillance
1. Passive
surveillance
Integrated
surveillance
Data is collected by
Existing rules
Integrated into
Routine HC delivery
Formalized
Activated passive
surveillance- Special
efforts made to
maximize reporting
-Reminders, Visits
Actively contacting &
collecting data.
Informalized
Sentinel
Surveillance
Choosing a key
location to monitor
For a condition of
interest
Using a single infrastructure
Gathering about multiple
diseases or behaviors
To several intervention
programs

4. 1. Monitoring disease trends
2. Describing natural history of diseases
3. Identifying epidemics or new syndromes
4. Monitoring changes in infectious agents
5. Identifying areas for research
6. Evaluating hypotheses
7. Planning public health policy
8. Evaluating public health policy/interventions
9. Projecting future needs
10. Monitoring risk factors
Uses

5. Steps in Surveillance
1. Establish objectives
2. Develop case definition
3. Develop data collection source
4. Develop data collection instrument
5. Field test methods
6. Develop Analytic approach
7. Determine Information dissemination mechanism
8. Determine evaluation method

6. The dynamic vision
Reporting
Feedback
Telephone, Mail,
Web site, Epid bulletin
Evaluation
Results of action
Results of surveillance
Analysis
Data validation
Data Reliability
Descriptive analysis
Hypothesis generation
Interpretation
Disease trends
Identifying epidemics
Evaluating public policy
Future projects
Paper, Telephone, Fax
E-mail, Web based
Data
Action
Control
Preventive
Policy
Information
Organizing data
Decision
How to control
How to prevent
Policy decisions?
Active
Passive
Health care system
Public health authority

7. Methodologies
Active
Actively contacting &
collecting data.
Informalized
More consistent data
Useful for disease of importance
Motivated staff
Fast process
Expensive
Only detect targeted diseases
May not representative
Passive
Data is collected by
Existing rules
Formalized
Inexpensive
Standardized
Identifying Epidemics
Detecting emerging diseases
Under reporting
Incomplete data
Slow process
Concept
Advantages
Disadvantages
Screening