title: Monitoring epidemic alert levels by analyzing Internet search volume.
abstract: The prevention of infectious diseases is a global health priority area. The early detection of possible epidemics is the first and important defense line against infectious diseases. However, conventional surveillance systems, e.g., the Centers for Disease Control and Prevention (CDC), rely on clinical data. The CDC publishes the surveillance results weeks after epidemic outbreaks. To improve the early detection of epidemic outbreaks, we designed a syndromic surveillance system to predict the epidemic trends based on disease-related Google search volume. Specifically, we first represented the epidemic trend with multiple alert levels to reduce the noise level. Then, we predicted the epidemic alert levels using a continuous density HMM, which incorporated the intrinsic characteristic of the disease transmission for alert level estimation. Respective models are built to monitor both national and regional epidemic alert levels of the U.S. The proposed system can provide real-time surveillance results, which are weeks before the CDC's reports. This paper focusses on monitoring the infectious disease in the U.S., however, we believe similar approach may be used to monitor epidemics for the developing countries as well.
authors.affiliation: College of Communications Engineering, Chongqing University, Chongqing 400044, China. zxc@cqu.edu.cn
authors.forename: Xichuan
authors.initials: X
authors.lastname: Zhou
authors.forename: Qin
authors.initials: Q
authors.lastname: Li
authors.forename: Zhenglin
authors.initials: Z
authors.lastname: Zhu
authors.forename: Han
authors.initials: H
authors.lastname: Zhao
authors.forename: Hao
authors.initials: H
authors.lastname: Tang
authors.forename: Yujie
authors.initials: Y
authors.lastname: Feng
mesh_terms: D002487:Centers for Disease Control and Prevention, U.S.; D058872:Epidemics / Q000706:statistics & numerical data*; D006505:Hepatitis; D006801:Humans; D020407:Internet / Q000706:statistics & numerical data*; D008390:Markov Chains; D008962:Models, Theoretical; D062486:Public Health Surveillance / Q000379:methods*; D057386:Search Engine / Q000706:statistics & numerical data*; D009626:Terminology as Topic; D014481:United States / Q000453:epidemiology