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

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.

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.

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

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

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.

Syndromic Surveillance Process

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

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

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

Electronic ED Data - Hospital A, August 8, 2004 -- CK s. x3 -- NG ER VA Date Time Sex Age Birth date Chief Complaint ---------------------------------------------------------- 08/08/2004 00:28 Female 13 01/31/1991 MIGRAINE NAUSEA 08/08/2004 00:38 Female 29 08/23/1974 COUGH,FEVER 08/08/2004 00:50 Male 48 09/01/1955 HUMAN BITE TO CHEST 08/08/2004 01:44 Male 53 07/29/1951 ABD PAIN, GENERAL 08/08/2004 09:00 Male 6 02/16/1998 N & VOMITING X 3 08/08/2004 09:21 Male 50 07/21/1954 SPRAIN ANKLE 08/08/2004 09:29 Female 1 03/21/2004 CRYING & FUSSINESS 08/08/2004 09:42 - Hospital A, August 8, 2004

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 

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

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

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

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

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

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.

Challenges and Limitations

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.

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.

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.

Policy Issues Example: The Boston City Health Commission

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

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

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…

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).

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

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

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

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

Final Thoughts

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.

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. www.cste.org - position statements

For more information: Websites: www.syndromic.org http://www.cdc.gov/epo/dphsi/syndromic http://www.bt.cdc.gov/surveillance/ears

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.