Bioterrorism Syndromic Surveillance: A Dual-Use Approach with Direct Application to the Detection of Infectious Disease Outbreaks

The threat of bioterrorism forces the public health infrastructure to focus attention on overall issues related to challenges posed by emerging and re-emerging infectious diseases. There is a crucial need to strengthen existing surveillance systems and to validate real-time approaches to surveillance that can provide timely alerts of epidemics whether they occur naturally or through a bioterrorism attack. The purpose of this study is to implement and evaluate a bioterrorism syndromic surveillance system called BioDefend™, to determine if the system could detect a potential epidemic/bioterrorism attack within 24-36 hours, more rapidly than it would be identified by routine health surveillance. This sentinel surveillance study was conducted in theme parks, theme park referral hospitals and clinics, and a military hospital and clinics in the Central Florida area. A six-month period of baseline data collection was completed at all surveillance sites for the purposes of serving as the comparison for the test period. The test period comsisted of five months and served to validate the system. The baseline was also used to identify normal illness trends and seasonality patterns so that thresholds could be established on which to determine significant syndromic aberrations. The web-based reporting system enabled near real-time data entry. The syndromic and demographic information then was processed in an automated analysis system to provide a mechanism for alerting surveillance sites when significant rises in reported syndromes and/or clinic/hospital daily visits exceeded the established thresholds. A pocket PC/phone device enabled staff to receive notification of alerts 24/7. The surveillance system was evaluated by comparing regional, state, and national surveillance data to equivalent syndromic data reported from BioDefend™. After comparing these data, it was determined that the BioDefend™ system detected two epidemics of public health importance more than one month before they were identified through routine regional and state, regional, and national surveillance methods. The specific syndromes identified earlier than the State of Florida surveillance were “gastroenteritis” and “influenza-like illness.” This study has examined whether or not the BioDefend™ surveillance system is useful in the context of the above referenced surveillance sites, and whether it could serve as a national model for syndromic surveillance