Objective: To analyze the spatial and temporal distribution characteristics of seasonal A(H3N2) influenza [influenza A(H3N2)] in China and to provide a reference for scientific prevention and control. Methods: The influenza A(H3N2) surveillance data in 2014-2019 was derived from China Influenza Surveillance Information System. A line chart described the epidemic trend analyzed and plotted. Spatial autocorrelation analysis was conducted using ArcGIS 10.7, and spatiotemporal scanning analysis was conducted using SaTScan 10.1. Results: A total of 2 603 209 influenza-like case sample specimens were detected from March 31, 2014, to March 31, 2019, and the influenza A(H3N2) positive rate was 5.96%(155 259/2 603 209). The positive rate of influenza A(H3N2) was statistically significant in the north and southern provinces in each surveillance year (all P<0.05). The high incidence seasons of influenza A (H3N2) were in winter in northern provinces and summer or winter in southern provinces. Influenza A (H3N2) clustered in 31 provinces in 2014-2015 and 2016-2017. High-high clusters were distributed in eight provinces, including Beijing, Tianjin, Hebei, Shandong, Shanxi, Henan, Shaanxi, and Ningxia Hui Autonomous Region in 2014-2015, and high-high clusters were distributed in five provinces including Shanxi, Shandong, Henan, Anhui, and Shanghai in 2016-2017. Spatiotemporal scanning analysis from 2014 to 2019 showed that Shandong and its surrounding twelve provinces clustered from November 2016 to February 2017 (RR=3.59, LLR=9 875.74, P<0.001). Conclusion: Influenza A (H3N2) has high incidence seasons with northern provinces in winter and southern provinces in summer or winter and obvious spatial and temporal clustering characteristics in China from 2014-2019.
目的： 分析我国季节性A（H3N2）［A（H3N2）］亚型流感的时空分布特征，为流感的科学防控提供参考。 方法： 2014-2019年A（H3N2）流感监测数据来源于中国流感监测信息系统，分析和绘制折线图描述流行趋势，采用ArcGIS 10.7软件进行空间自相关分析，采用SaTScan 10.1软件进行时空扫描分析。 结果： 2014年3月31日至2019年3月31日共检测2 603 209例流感样病例标本，A（H3N2）流感检测阳性率为5.96%（155 259/2 603 209）。每个监测年度A（H3N2）流感阳性率在南、北方省份差异均有统计学意义（均P<0.05）。A（H3N2）流感在北方省份冬季高发，在南方省份夏季或冬季高发。2014-2015年和2016-2017年A（H3N2）流感在31个省份存在空间聚集性。2014-2015年高-高聚集区分布在8个省份（北京市、天津市、河北省、山东省、山西省、河南省、陕西省和宁夏回族自治区）；2016-2017年高-高聚集区分布在5个省份（山西省、山东省、河南省、安徽省和上海市）。2014-2019年时空扫描分析结果显示，2016年11月至2017年2月山东省及其周边12个省份为一类聚集区（RR=3.59，LLR=9 875.74，P<0.001）。 结论： 我国2014-2019年A（H3N2）流感具有在北方省份冬季流行、南方省份夏季或冬季流行的季节性分布特征且存在明显的时空聚集性。.