1. Implementing a Syndromic Surveillance System: Objectives, Policy and Cost
Aaron Fleischauer, PhD, MPH
Bioterrorism Preparedness and Response Program
National Center for Infectious Diseases

2. Objectives What is Syndromic Surveillance?
Where syndromic surveillance fits in?
How it works?
Challenges and limitations
Policy issues with implementing a system
Cost and burden
This presentation will provide of overview of several public health preparedness and surveillance initiatives in the United States. I will describe the evolving field of syndromic surveillance, and the application of post-event surveillance. I will then briefly discuss the methods involved with aberration detection. The latter part of this talk will focus on the Laboratory Response Network, and the BioWatch program.

3. Definition
“The collection and analysis of health-related data that precede diagnosis and signal a sufficient probability of case or an outbreak to warrant further public health response.”
Syndromic surveillance, like most public health surveillance systems involves the collection of data at the local level. It’s definition covers a broad spectrum of very different pieces of information and employs the use of multiple types and sources of data. Generally these data sources precede clinical or laboratory diagnosis, and often involve the use of specific clinical signs, symptoms and syndromes identified as potential predictors of infectious disease of interest.

4. Rationale PRODROME SEVERE ILLNESS Number of Cases RELEASE
The rationale for using syndromic surveillance can be simplified in this graph. Following a hypothetical release or point source exposure most category A disease will present, after their incubation period, with an early prodrome usually marked by fever and often characteristic signs and symptoms, but usually non-specific signs and symptoms. Following the prodrome, severe illness occurs. Patients with common and consistent severe illness reach a case threshold that initiates public health response. Likewise, patients with a common syndrome reach a threshold potentially days earlier and can initiate a public health investigation more timely, thereby reducing the impact of the outbreak or event.
Notifiable Disease Reporting
Syndromic Surveillance

5. Rationale PRODROME SEVERE ILLNESS Number of Cases EXPOSURE
The rationale for using syndromic surveillance can be simplified in this graph. Following a hypothetical release or point source exposure most category A disease will present, after their incubation period, with an early prodrome usually marked by fever and often characteristic signs and symptoms, but usually non-specific signs and symptoms. Following the prodrome, severe illness occurs. Patients with common and consistent severe illness reach a case threshold that initiates public health response. Likewise, patients with a common syndrome reach a threshold potentially days earlier and can initiate a public health investigation more timely, thereby reducing the impact of the outbreak or event.
Notifiable Disease Reporting
Syndromic Surveillance

6. Increase sensitivity & timeliness of outbreak detection
Strategies
Make outbreaks of any kind & individual cases of unusual disease officially reportable 24/7
Routine use of PFGE fingerprinting (PulseNet) and the Laboratory Response Network (LRN) with sharing of information across states to identify clusters/ cases.
Automated analysis of reportable disease/lab data
Implement syndromic surveillance
Environmental monitoring (e.g., Biowatch, BDS)
NOTES:
In the case of a bioterrorist (BT) event, the state would still invite CDC to participate in the epidemiologic investigation, but the FBI would also bring CDC in as a Federal resource.

7. Syndromic Surveillance Process

8. Syndromic Surveillance Data Sources
Laboratory Tests
EMS
Nursing Hotlines
Emergency Departments
Syndromic Surveillance Data Sources
Poison Control
Veterinarian Clinics
Prescription Drugs
School Absentee
Over-the-counter

9. Syndromic Surveillance Process
ED collects data on each patient
Step 1
Syndromic Surveillance Process

10. Syndromic Surveillance Process
Send data (e.g., 24 hours) via secure server to Health Department
ED collects data on each patient
Step 2
Syndromic Surveillance Process

11. Electronic ED Data - Hospital A, August 8, 2004-- CK s. x3 -- NG ER VA
Date Time Sex Age Birth date Chief Complaint
08/08/ :28 Female /31/1991 MIGRAINE NAUSEA
08/08/ :38 Female /23/1974 COUGH,FEVER
08/08/ :50 Male /01/1955 HUMAN BITE TO CHEST
08/08/ :44 Male /29/1951 ABD PAIN, GENERAL
08/08/ :00 Male /16/1998 N & VOMITING X 3
08/08/ :21 Male /21/1954 SPRAIN ANKLE
08/08/ :29 Female /21/2004 CRYING & FUSSINESS
08/08/ :42
- Hospital A, August 8, 2004

12. Syndromes  [ ] Upper or lower respiratory tract infection with fever
[ ]
Upper or lower respiratory tract infection with fever
Diarrhea/ gastroenteritis
Rash with fever
Sepsis or non-traumatic shock
Meningitis or encephalitis
Botulism-like syndrome
Unexplained death with history of fever
Lymphadenitis with fever
Localized cutaneous lesion
Myalgia with fever/ rigors and malaise 

13. Syndromic Surveillance Process
Send data (e.g., 24 hours) via secure server to HD
Hospital can receive reports or view data
ED collects data on each patient
Step 3
Syndromic Surveillance Process
HD performs aberration detection and analyses

14. Early Aberration Reporting System (EARS)
Washington County
ALL HOSPITALS
Respiratory with Fever/ ILI
Signal
Moving 7-day baseline

15. Syndromic Surveillance Process
Send data (e.g., 24 hours) via secure server to HD
Hospital can receive reports or view data
ED collects data on each patient
Step 4
Syndromic Surveillance Process
HD performs aberration detection and analyses
Signals require further analysis and interpretation

16. Total GI (Last 24 Hrs): 2
Total GI (Last 24 Hrs): 0
Total GI (Last 24 Hrs): 0
Total GI (Last 24 Hrs): 1
Total GI (Last 24 Hrs): 0
Total GI (Last 24 Hrs): 3
Total GI (Last 24 Hrs): 2
Total GI (Last 24 Hrs): 4
Total GI (Last 24 Hrs): 1
Total GI (Last 24 Hrs): 1

17. Syndromic Surveillance Process
Send data (e.g., 24 hours) via secure server to HD
Hospital can receive reports or view data
ED collects data on each patient
Step 5
Syndromic Surveillance Process
HD performs aberration detection and analyses
Epidemiologists investigate Signals
Signals require further analysis and interpretation

18. Phased Response Strengths and limitations of statistical algorithms
Phase I
System attributes
Strengths and limitations of statistical algorithms
Sensitivity and specificity of data types (e.g., over-the-counter pharmaceuticals, chief complaint, diagnoses)
Consideration of data source (e.g., Target population)
Phase II
Descriptive analysis
Performing stratified analyses (by age, gender, time, geography)
Consistency of patient-specific reports
Phase III
Comparisons
Comparisons with alternate data sources
Interpreting of data within context (e.g. OTC drug sales)
Phase IV
Investigation
Field investigation, (Phone call, Visit, Review of records)
Syndromic surveillance, like most public health surveillance systems involves the collection of data at the local level. It’s definition covers a broad spectrum of very different pieces of information and employs the use of multiple types and sources of data. Generally these data sources precede clinical or laboratory diagnosis, and often involve the use of specific clinical signs, symptoms and syndromes identified as potential predictors of infectious disease of interest.

19. Challenges and Limitations

20. Signal What questions are being asked of these data? Limitations
Specific questions to non-specific data
Limitations
Signal to noise (false positives)
Signal desensitization
Cost and resources
Syndromic surveillance, like most public health surveillance systems involves the collection of data at the local level. It’s definition covers a broad spectrum of very different pieces of information and employs the use of multiple types and sources of data. Generally these data sources precede clinical or laboratory diagnosis, and often involve the use of specific clinical signs, symptoms and syndromes identified as potential predictors of infectious disease of interest.

21. Sufficient Probability
Assessed by performing validations
Validate syndrome case definitions
Validate system to detect outbreaks
Sensitivity and specificity
Improving sensitivity
Increase false positive rate
Syndromic surveillance, like most public health surveillance systems involves the collection of data at the local level. It’s definition covers a broad spectrum of very different pieces of information and employs the use of multiple types and sources of data. Generally these data sources precede clinical or laboratory diagnosis, and often involve the use of specific clinical signs, symptoms and syndromes identified as potential predictors of infectious disease of interest.

22. Response What signals warrant further public health response?
Thresholds
Sufficient size of the event
Among Syndromes
Do all data sources have a response?
Emergency Departments
Over-the-counter Pharmaceuticals
Syndromic surveillance, like most public health surveillance systems involves the collection of data at the local level. It’s definition covers a broad spectrum of very different pieces of information and employs the use of multiple types and sources of data. Generally these data sources precede clinical or laboratory diagnosis, and often involve the use of specific clinical signs, symptoms and syndromes identified as potential predictors of infectious disease of interest.

23. Policy Issues Example: The Boston City Health Commission

24. Background Previous outbreak detection systems
Reportable Disease Surveillance
Volume-based ED surveillance
Both mandated by City Regulation
Democratic National Convention
Pressure to implement electronic
ED-based syndromic surveillance

25. Stakeholders
All Hospitals and Urgent Care Centers operating an Emergency Department in Boston
HIPAA
Privacy rule expressly permits use of protected health information for:
Reportable disease reporting
Public health surveillance
Epidemiologic investigation
Includes patient identifiable information
Limited Data Set Rule

26. Public Health Regulation
DISEASE SURVEILLANCE AND REPORTING
REGULATION
PREAMBLE
WHEREAS, The Boston Public Health Commission is charged with protecting, preserving and promoting the health and well-being of all Boston residents, particularly those who are most vulnerable.
WHEREAS, The Boston Public Health Commission is charged with…

27. Disease Surveillance Regulation
All health care facilities in the City of Boston that operate or maintain an
emergency department and/or an urgent care facility, shall report for each visit during a twenty-four (24) hour period, to such emergency department or urgent care facility, the following information about each patient:
a. Age;
b. Gender;
c. Race/Ethnicity;
d. Residential zip code;
e. Chief complaint; and
f. Diagnostic code (if available).

30. CSTE concerns
Cost implications of monitoring syndromic surveillance systems and following up aberrations
With BT funding decreasing, evaluation of cost and effectiveness relative to other strategies for early detection of diseases of concern is badly needed

31. Estimating Cost Difficult to measure Parameters requiring estimates
Software packages
Data transfer mechanisms
Person-time and dedicated staff
R&D and Maintenance
Investigation of aberrations

32. Estimated Costs: NYC Start-up costs Electronic system
Developed from post-9/11 drop-in system
Paper-based with deployed staff to area hospitals
Electronic system
Direct annual costs estimated at $150,000/ year
Not including cost associated with:
Research and development
Surveillance for non-infectious outcomes
Data transmission costs incurred by hospitals

33. Aberration Detection Software
EARS (Early Aberration Reporting System)
Developed by CDC (Lori Hutwagner)
Shareware, available free of cost
RODS (Real-time Outbreak Detection Software)
Shareware, with ~$350/hour support/consult fees
Other packages from private vendors
May average ~$50,000

34. Final Thoughts

35. CSTE Recommendation
Need evaluation of syndromic surveillance and a critical determination made as to whether it should be used routinely for aberration detection – or only in special circumstances (public health events)?
We should not be expanding it without evaluation.

36. CSTE Position on Syndromic/ Bioterrorism Surveillance
Recommendations:
CDC form an advisory group to review all efforts at improving BT surveillance and advise re: which are worth keeping and funding, which should be encouraged of all states, and which should be scrapped.
NOTES:
In the case of a bioterrorist (BT) event, the state would still invite CDC to participate in the epidemiologic investigation, but the FBI would also bring CDC in as a Federal resource.
- position statements

37. For more information: Websites: www.syndromic.org

38. Signal Detection scenario Stoto et al. Chance 2004; 17(1): 19-24
Excess of 9 cases over two days
3X daily average
50% probability of alarm
Excess of 18 cases over 9 days
Not until 9th day
Syndromic surveillance, like most public health surveillance systems involves the collection of data at the local level. It’s definition covers a broad spectrum of very different pieces of information and employs the use of multiple types and sources of data. Generally these data sources precede clinical or laboratory diagnosis, and often involve the use of specific clinical signs, symptoms and syndromes identified as potential predictors of infectious disease of interest.