目的 了解2014—2024年度信阳市流感样病例(ILI)流行特征和流行毒株变化规律,为流感防控提供科学依据。方法 通过中国流感监测信息系统收集信阳市2014—2024监测年度ILI监测数据和实验室检测数据,采用描述流行病学方法分析流行特征。结果 2014—2024监测年度,累计报告ILI 87 642例,占就诊病例总数比例(ILI%)为1.79%,不同年度ILI%波动在0.50%~6.40%。ILI占比最大的年龄组为0~4岁组(33.99%),最小的是60岁及以上年龄组(9.80%)。7 705份ILI标本,1 489份标本流感病毒核酸阳性,核酸阳性率为19.33%(1 489/7 705),其中甲型、乙型和混合型流感病毒核酸阳性率分别为11.97%(922/7 705)、7.31%(563/7 705)和0.05%(4/7 705)。流感核酸阳性率居前3位的监测年度分别是2017—2018年(30.48%)、2021—2022年(29.67%)和2023—2024年(26.49%)。不同监测年度,流感核酸阳性率不同(χ²=405.465,P<0.001),甲乙型流感病毒分型不同(χ²=720.477,P<0.001)。不同年龄组间流感核酸阳性率不同(χ²=212.207,P<0.001),其中5~14岁组最高(27.39%),0~4岁组最低(11.45%);不同年龄组间流感病毒分型差异有统计学意义(χ²=17.322,P=0.002),各年龄组均以甲型流感病毒为主。不同监测年度流感优势株不同,以甲型为主,流行高峰多出现在当年的第48周至次年的第4周。结论 2014—2024监测年度信阳市流感在冬春季节高发,不同流感病毒亚型交替混合流行,甲型流感毒株为流行优势株,5~14岁人群是重点防控人群。

Objective To understand the epidemiological characteristics of influenza-like illness (ILI) and the patterns of prevalent strains in Xinyang from 2014 to 2024,in order to provide scientific basis for the prevention and control of influenza.Methods The data of ILI surveillance and laboratory test in the surveillance years from 2014 to 2024 in Xinyang were collected from the National Influenza Surveillance Network,and descriptive epidemiological method was used to analyze the epidemic characteristics.Results A total of 87 642 ILI cases were reported from 2014 to 2024,accounting for 1.79% of all visiting patients,proportions of ILI cases among all patients (ILI%) ranged from 0.50% to 6.40% in different years.The proportion of all ILI cases was highest in age group 0-4 years (33.99%),and was lowest in the people aged 60 years old and above (9.80%).Among 7 705 ILI samples,1 489 samples were positive for influenza nucleic acid,the positive rate was 19.33%(1 489/7 705),with the positive rates of type A,type B and mixed types of influenza virus were 11.97%(922/7 705),7.31%(563/7 705),0.05%(4/7 705),respectively.The top three surveillance years with the highest influenza nucleic acid positive rates were 2017-2018 (30.48%),2021-2022 (29.67%) and 2023-2024 (26.49%),respectively.In different surveillance years,the positive rate of influenza nucleic acid was different (χ²=405.465,P<0.001),and the influenza A and B virus typing was different (χ²=720.477,P<0.001).The positive rate of influenza nucleic acid was different among different age groups (χ²=212.207,P<0.001),and the positive rate was highest in the 5-14 years old group (27.39%),while was lowest in the 0-4 years old group (11.45%).The difference in influenza virus typing among different age groups was statistically significant (χ²=17.322,P=0.002),and influenza A virus was the dominant strain in all age groups.The dominant strains of influenza were different in different surveillance years,with influenza A virus was the dominant strain,and the peak of the pandemic occurred from the 48th week of the current year to the 4th week of the following year.Conclusion Influenza was prevalent mainly in winter and spring from 2014 to 2024 in Xinyang,with alternating mixed prevalence of different influenza virus types.Influenza A strain is the epidemic dominant strain.The age group of 5-14 years is the key population for prevention and control.