Early detection of influenza outbreaks using the DC Department of Health's syndromic surveillance system

<p>Abstract</p> <p>Background</p> <p>Since 2001, the District of Columbia Department of Health has been using an emergency room syndromic surveillance system to identify possible disease outbreaks. Data are received from a number of local hospital emergency rooms and analyzed daily using a variety of statistical detection algorithms. The aims of this paper are to characterize the performance of these statistical detection algorithms in rigorous yet practical terms in order to identify the optimal parameters for each and to compare the ability of two syndrome definition criteria and data from a children's hospital versus vs. other hospitals to determine the onset of seasonal influenza.</p> <p>Methods</p> <p>We first used a fine-tuning approach to improve the sensitivity of each algorithm to detecting simulated outbreaks and to identifying previously known outbreaks. Subsequently, using the fine-tuned algorithms, we examined (i) the ability of unspecified infection and respiratory syndrome categories to detect the start of the flu season and (ii) how well data from Children's National Medical Center (CNMC) did versus all the other hospitals when using unspecified infection, respiratory, and both categories together.</p> <p>Results</p> <p>Simulation studies using the data showed that over a range of situations, the multivariate CUSUM algorithm performed more effectively than the other algorithms tested. In addition, the parameters that yielded optimal performance varied for each algorithm, especially with the number of cases in the data stream. In terms of detecting the onset of seasonal influenza, only "unspecified infection," especially the counts from CNMC, clearly delineated influenza outbreaks out of the eight available syndromic classifications. In three of five years, CNMC consistently flags earlier (from 2 days up to 2 weeks earlier) than a multivariate analysis of all other DC hospitals.</p> <p>Conclusions</p> <p>When practitioners apply statistical detection algorithms to their own data, fine tuning of parameters is necessary to improve overall sensitivity. With fined tuned algorithms, our results suggest that emergency room based syndromic surveillance focusing on unspecified infection cases in children is an effective way to determine the beginning of the influenza outbreak and could serve as a trigger for more intensive surveillance efforts and initiate infection control measures in the community.</p

Evaluating Statistical Methods for Syndromic Surveillance

Statistical Methods in Counterterrorism: Game Theory, Modeling, Syndromic Surveillance, and Biometric Authentication, chapter

Distribution of blood lead levels for the target group (children 6 years of age, pregnant women, and nursing women) tested during the 8-month period in 2004 (as of 12 July 2004)

<p><b>Copyright information:</b></p><p>Taken from "Elevated Lead in Drinking Water in Washington, DC, 2003–2004: The Public Health Response"</p><p></p><p>Environmental Health Perspectives 2007;115(5):695-701.</p><p>Published online 17 Jan 2007</p><p>PMCID:PMC1868000.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI</p

Distribution of blood lead levels among children 6 years of age who were residents of the District of Columbia and were tested in the screening program during the 8-month period in 2004 (as of 12 July 2004)

<p><b>Copyright information:</b></p><p>Taken from "Elevated Lead in Drinking Water in Washington, DC, 2003–2004: The Public Health Response"</p><p></p><p>Environmental Health Perspectives 2007;115(5):695-701.</p><p>Published online 17 Jan 2007</p><p>PMCID:PMC1868000.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI</p