community-based measures for mitigating the 2009 h1n1 pandemic in china以社区为基础的措施缓解2009年甲型h1n1流感大流行在中国.pdf

Community-Based Measures for Mitigating the 2009 H1N1 Pandemic in China 1 2 2 2 3 2 Sanyi Tang , Yanni Xiao , Youping Yang , Yicang Zhou , Jianhong Wu , Zhien Ma * 1 College of Mathematics and Information Science, Shaanxi Normal University, Xi’an, People’s Republic of China, 2 Department of Applied Mathematics, Xi’an Jiaotong University, Xi’an, People’s Republic of China, 3 Centre for Disease Modeling, York University, Toronto, Ontario, Canada Abstract Since the emergence of influenza A/H1N1 pandemic virus in March–April 2009, very stringent interventions including Fengxiao were implemented to prevent importation of infected cases and decelerate the disease spread in mainland China. The extent to which these measures have been effective remains elusive. We sought to investigate the effectiveness of Fengxiao that may inform policy decisions on improving community-based interventions for management of on-going outbreaks in China, in particular during the Spring Festival in mid-February 2010 when nationwide traveling will be substantially increased. We obtained data on initial laboratory-confirmed cases of H1N1 in the province of Shaanxi and used Markov-chain Monte-Carlo (MCMC) simulations to estimate the reproduction number. Given the estimates for the exposed and infectious periods of the novel H1N1 virus, we estimated a mean reproduction number of 1.68 (95% CI 1.45–1.92) and other A/H1N1 epidemiological parameters. Our results based on a spatially stratified population dynamical model show that the early implementation of Fengxiao can delay the epidemic peak significantly and prevent the disease spread to the general population but may also, if not implemented appropriately, cause