The Institute of Statistical Mathematics, 10-3 Midoricho, Tachikawa, Tokyo 190-8562, Japan.
Math Biosci. 2013 Nov;246(1):47-54. doi: 10.1016/j.mbs.2013.08.009. Epub 2013 Sep 4.
In order to understand the evolution of the 2009 influenza A (H1N1) pandemic within local regions of Japan, we studied the significance of regional migration between these regions. For this purpose, we have employed an extended SEIR model to describe the immigration of infected people and the stochastic variation of the infectious efficiency. We then applied a data assimilation technique in order to study how the agreement of the simulation results with the observed data depends on the presence/absence of immigration and the degree of variation of the infectious efficiency. Reproducibility is evaluated by log-likelihood values. The log-likelihood does not indicate the significance of immigration. Although there are multiple waves in the time course of the number of reported infected individuals, these waves could be explained by the stochastic nature of infectious events.
为了了解 2009 年甲型 H1N1 流感在日本局部地区的演变情况，我们研究了这些地区之间区域迁移的意义。为此，我们采用了扩展的 SEIR 模型来描述感染人群的输入和传染性效率的随机变化。然后，我们应用了数据同化技术来研究模拟结果与观测数据的一致性如何取决于移民的存在/不存在以及传染性效率的变化程度。通过对数似然值来评估可重复性。对数似然值并不能表明移民的重要性。虽然报告的感染人数在时间上有多个波峰，但这些波峰可以用传染性事件的随机性来解释。
