Application of the moving epidemic method in the estimation of influenza epidemic thresholds and intensity classification in Anhui province during winter and spring seasons
10.19405/j.cnki.issn1000–1492.2026.07.010
- VernacularTitle:移动流行区间法在安徽省冬春季流感流行阈值估计与强度分级中的应用
- Author:
Biao ZHU
1
;
Meng ZHU
1
;
Lei GONG
1
;
Shuwen LI
1
;
Jiabing WU
1
;
Qingqing ZHU
1
Author Information
1. Institute for Infectious Disease Control and Prevention， Anhui Provincial Center for Disease Control and Prevention， Hefei 230601
- Publication Type:Journal Article
- Keywords:
influenza;
moving epidemic method;
threshold;
early warning;
intensity grading;
winter and spring
- From:
Acta Universitatis Medicinalis Anhui
2026;61(7):1231-1236
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo develop an early - warning approach for influenza in Anhui province using the moving epidemic method （MEM）， offering a scientific basis for influenza prevention and control in the province. MethodsBased on the surveillance data reported weekly by influenza sentinel hospitals and network laboratories in the “China Influenza Surveillance Information System”， the weekly influenza virus detection positive rate （positive rate， PR） across the province was analyzed. The MEM was used to estimate the epidemic threshold and classification intensity threshold of influenza in Anhui province before and after the COVID-19 pandemic， respectively. The early warning effect of the MEM was evaluated using cross-validation. ResultsEpidemic and graded intensity thresholds of influenza were derived using PR and MEM. Prior to the COVID-19 pandemic， the starting， medium-intensity， high-intensity， extremely-high-intensity， and ending thresholds of influenza epidemics were 17.08%， 38.47%， 53.20%， 59.71%， and 12.34% respectively. At this point， the model exhibited sensitivity of 0.98， specificity of 0.86， Matthews correlation coefficient of 0.84， and Youden index of 0.84. After the COVID-19 pandemic， these thresholds were 25.61%， 43.81%， 63.29%， 74.46%， and 17.82% respectively. At this point， the model demonstrates sensitivity of 0.86， specificity of 0.92， Matthews correlation coefficient of 0.78， and Youden index of 0.77. ConclusionMEM shows good applicability in estimating the epidemic and graded intensity thresholds of influenza during the winter and spring in Anhui province. Both the influenza epidemic threshold and graded intensity thresholds after the COVID-19 pandemic are higher than those before the pandemic.
