杭州市2016—2020监测年流行性感冒累积和控制图法预警效果分析

Early warning effect of influenza CUSUM control chart method of 2016—2020 monitoring year in Hangzhou

目的了解杭州市2016—2020监测年的流感流行特征,用累积和控制图法进行预警分析,并对预警效果进行评价。方法以累积和控制图法对杭州市2016年第14周至2020年第13周流感样病例监测数据进行预警分析,结合敏感度、特异度、阳性预测值、约登指数等指标,比较不同参数模型下的预警效果。结果2016—2020年全市哨点医院共报告门急诊接诊ILI病例百分比为2.22%,流感病毒核酸阳性率为21.03%。当预警值H=2σ时,累积和控制图模型在5个流感病毒阳性率高峰期皆产生预警信号,按照产生预警信号的周数来看,预警敏感度为67.65%,特异度为85.89%,阳性预测值为50.00%,阴性预测值为92.72%,约登指数为0.5354。结论累积和控制图法在杭州市流感预警中有较好的应用价值。

Objective To understand the influenza epidemic characteristics of the 2016-2020 monitoring year in Hangzhou,use the CUSUM control chart method to perform early warning analysis,and evaluate the early warning effect.Methods Early warning analysis of influenza-like case surveillance data in Hangzhou from week 14 of 2016 to week 13 of 2020 was conducted using CUSUM control chart method.The CUSUM control chart combined with indicators such as sensitivity,specificity,positive predictive value,and Yoden index,were used to compare the early warning effects of different parameter models.Results From 2016 to 2020,sentinel hospitals in Hangzhou reported a total of 2.22%of ILI cases received in outpatient and emergency departments.The positive rate of influenza virus nucleic acid was 21.03%.When the early warning value H=2σ,the CUSUM control chart model generated early warning signals during the 5 peak periods of influenza virus positive rate.According to the number of weeks in which the early warning signals were generated,the early warning sensitivity was 67.65%and specificity was 85.89%.The positive predictive value was 50.00%,negative predictive value was 92.72%,and Youden index was 0.5354.Conclusion The CUSUM control chart method has good application value in the early warning of influenza in Hangzhou.