Analysis on spatial and temporal clustering of dengue fever epidemic in Zhejiang, 2004−2016

Objective To investigate the spatial and temporal distribution of dengue fever in Zhejiang province from 2004 to 2016 and provide scientific evidence for dengue fever prevention and control.

Methods The information of dengue fever cases of Zhejiang province from 2004 to 2016 was collected from Chinese Center for Disease Control and Prevention. Software SaTScan was used to analyze the spatial and temporal clustering of dengue fever cases, and software ArcGIS was used for the result visualization.

Results Spatial and temporal scan statistics detected 2 clusters (P＜0.05) of dengue cases in Zhejiang during 2004–2016. The class Ⅰ cluster was in Yiwu (1 August 2009 to 30 September 2009) and the class Ⅱ cluster was in Cixi (1 September 2004 to 31 October 2004). Sporadic outbreaks had one class I cluster in Yiwu and Pujiang (1 August 2012 to 31 December 2016), and two class Ⅱ clusters in the urban areas of Ningbo (1 July 2013 to 31 October 2016) and Hangzhou (1 July 2013–30 November 2016).

Conclusion The distribution pattern of dengue fever in Zhejiang from 2004 to 2016 showed clustering trend. Yiwu and the urban areas of Ningbo and Hangzhou were at high risk for dengue fever importation. It is necessary to develop effective dengue fever prevention and control strategy in Zhejiang