The Applicability and Usefulness of Emergency Department Syndromic Surveillance Using a Computed Data Source for Epidemic Keratoconjunctivitis and Meningitis

Abstract

Purpose: This study was designed to evaluate the applicability and usefulness of emergency department (ED) syndromic surveillance using a computerized data source for highly contagious, public health related diseases such as conjunctivitis and meningitis. Methods: Between Jan 1 2007 and Dec 31 2008 we conducted a retrospective, observational study through consecutive enroll ment of individuals at a university hospital with an ED census of about 156,000. ED patient data were obtained from a computerized data system, the National Emergency Department Information System (NEDIS). Predefined symptoms including red eye, eye injection / discharge / itching, headache, nausea, vomiting and predefined signs such as fever comparable with conjunctivitis and meningitis and ED discharge diagnosis were used as data for syndromic surveillance. Data about spinal tapping were used for agreement analysis. Results: We enrolled 714 patients for ED syndromic conjunctivitis and 1,889 for ED syndromic meningitis during the study period. A positive correlation was demonstrated between ED syndromic conjunctivitis data and national ophthalmologic sentinel survey data (Pearson correlation = 0.696; p<0.001). The agreement (kapha value) between ED syndromic meningitis using chief complaints and ED discharge diagnosis and ED syndromic meningitis using chief complaints and spinal tapping order was 0.665 (p<0.001). Real outbreaks were recognized 2 to 4 weeks early by both ED syndromic surveillance of conjunctivitis and meningitis. Conclusion: ED syndromic surveillance methods are applicable and useful for surveillance of conjunctivitis and meningitis. Further study is needed to clarify the effectiveness of ED syndromic surveillance and the likelihood of early recognition in highly contagious public health related diseases.