Telehealth Ontario detection of gastrointestinal illness outbreaks

Objective: Prompt detection of infectious disease outbreaks and rapid introduction of mitigation strategies is a primary concern for public health, emergency and security management organizations. Traditional surveillance methods rely on astute clinical detection and reporting of disease or laboratory confirmation. Although effective, these methods are slow, dependent on physician compliance and delay timely, effective intervention. To address these issues, syndromic surveillance programs have been integrated into the health care system at the earliest points of access; in Ontario, these points are primary care providers, emergency departments (ED), and Telehealth Ontario. This study explores the role of Telehealth Ontario, a telephone helpline, as an early warning system for detection of gastrointestinal (GI) illness. Methods: Retrospective time-series analysis of the National Ambulatory Care Reporting System (NACRS) ED discharges and Telehealth Ontario data for GI illness from June 1, 2004 to March 31, 2006. Results: Telehealth Ontario recorded 184,904 calls and the NACRS registered 34,499 ED visits for GI illness. The Spearman rank correlation coefficient was calculated to be 0.90 (p<0.0001). Time-series analysis resulted in significant correlation at lag (weekly) 0 indicating that increases in Telehealth Ontario call volume correlate with increases in NACRS data for GI illness. Conclusion: Telehealth Ontario call volume fluctuation reflects directly on ED GI visit data on a provincial basis. Telehealth Ontario GI call complaints are a timely, novel and representative data stream that shows promise for integration into a real-time syndromic surveillance system for detection of unexpected events.