Yu H Y, Sun C K, Deng F, Dai Q G
Department of Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing 210009, China.
Department of Remote Sensing, Jiangsu Provincial Geomatics Center, Nanjing 210013, China.
Zhonghua Yu Fang Yi Xue Za Zhi. 2023 Dec 6;57(12):2129-2133. doi: 10.3760/cma.j.cn112150-20230414-00289.
By analyzing the epidemic characteristics of influenza during the COVID-19 epidemic in Jiangsu Province from 2020 to 2022, it found that 90 721 influenza-like case samples were collected in Jiangsu Province from 2020 to 2022, of which 6 732 were nucleic acid-positive samples, with an average positive detection rate of 7.4% in three years. The annual positive detection rate presented a U-shaped distribution, with positive detection rates of 4.4%, 3.2% and 14.7%, respectively, with statistically significant differences (=12 126.00, <0.001). During the seasonal peak period of influenza from 2020 to 2022, there was a significant decrease in the intensity of the two influenza activity peaks that occurred before the virus became fully prevalent in the population. The first peak occurred from January to February 2020, and the positive detection rate of influenza nucleic acid decreased from 54.4% (317/583) in the third week to 2.1% (12/584) in the eighth week, with a statistically significant difference (χ=394.49<0.001) The second occurred in December 2022, and the positive detection rate of influenza nucleic acid decreased from 14.9% (90/605) at the 49th week to 1.9% (11/572) at the 52nd week, with a statistically significant difference (χ=62.88, <0.001). The influenza epidemic in Jiangsu Province from 2020 to 2022 had obvious seasonal characteristics, and the distribution differences of influenza virus-positive cases in each month were statistically significant (χ=858.00, <0.001), with two epidemic peaks each year: winter, spring (December to March of the following year), and summer, and autumn (July to November). The epidemic strains were the B-V strain and seasonal H3 strain, respectively. There was a statistically significant difference in the positive detection rate of influenza cases detected in different age groups (χ=60.00, <0.001). The age group between 5 and 14 years old had the highest influenza-positive detection rate (10.4%), while the age group≥60 years old had a relatively low influenza-positive detection rate (5.1%). The positive detection rate decreased with the increase in the age group (=12.82, <0.001).
通过分析2020年至2022年江苏省新冠肺炎疫情期间流感的流行特征，发现2020年至2022年江苏省共采集90721份流感样病例样本，其中核酸阳性样本6732份，三年平均阳性检出率为7.4%。年度阳性检出率呈U型分布，分别为4.4%、3.2%和14.7%，差异有统计学意义（=12126.00，<0.001）。在2020年至2022年流感季节性高峰期，在病毒在人群中完全流行之前出现的两个流感活动高峰强度显著下降。第一个高峰出现在2020年1月至2月，流感核酸阳性检出率从第三周的54.4%（317/583）降至第八周的2.1%（12/584），差异有统计学意义（χ=394.49<0.001）；第二个高峰出现在2022年12月，流感核酸阳性检出率从第49周的14.9%（90/605）降至第52周的1.9%（11/572），差异有统计学意义（χ=62.88，<0.001）。2020年至2022年江苏省流感疫情具有明显的季节性特征，各月流感病毒阳性病例分布差异有统计学意义（χ=858.00，<0.001），每年有两个流行高峰：冬春季（12月至次年3月）和夏秋季（7月至11月），流行毒株分别为B-V系和季节性H3毒株。不同年龄组流感病例阳性检出率差异有统计学意义（χ=60.00，<0.001），5至14岁年龄组流感阳性检出率最高（10.4%），≥60岁年龄组流感阳性检出率相对较低（5.1%），阳性检出率随年龄组增加而降低（=12.82，<0.001）。
