Steps to Evaluate a Surveillance System.

1. Describe the PUBLIC HEALTH IMPORTANCE of health event under surveillance.
2. Describe the SURVEILLANCE SYSTEM to be evaluated.
   • List its objectives
   • Describe the health event - case definition / population definition
   • Draw a flowchart of system
   • Describe the systems components - ie. cover each 'principle of surveillance'
3. Indicate the level of USEFULNESS.
4. COST
5. Evaluate QUALITY by assessing attributes:
   • Simplicity
   • Flexibility
   • Acceptability
   • Sensitivity
   • Representative
   • Timeliness
6. List CONCLUSIONS AND RECOMMENDATIONS.

Outbreak Investigation

Method 1: Use -mnemonic 'CCDC's HATE IT' (in addition to other 'STEPS')

Method 2:

1. Define an outbreak
2. Define the objectives of outbreak investigation
3. State the steps taken in an outbreak investigation

1. Outbreak = A localised epidemic of two or more cases of disease related in time and or place in excess of normal expectancy.
2. Objectives
   1. Identify source and mode of spread
   2. Interrupt further transmission
   3. Prevent secondary spread
   4. Educate
   5. Introduce future preventative measures
   6. (prosecute)
3. Steps of outbreak investigation:
   

   1.	Preliminary assessment is it an outbreak? confirm numbers Is further investigation needed? Literature review Form Outbreak control team (OCT) Initiate immediate control measures
   2.	Case definition and case findings - Time/Place/Person/Clinical symptoms/ laboratory results
   3.	Descriptive study - data collection and analysis --> epidemic curve --> generation of hypothesis
   4.	Analytical study - cohort or case control - to test hypothesis
   5.	Verify hypothesis - microbiological or environmental tests
   6.	Initiate control measures : - Remove source - isolate/ treat case, destroy food, close shop - protect those at risk - hygiene, handwashing, water boiling and prophylaxis eg. hepatitis B injections. - prevent recurrence - recommendations, guidelines
   7.	Communication - media, reports, guidelines