关键词: 流行性感冒, 流感样病例, 实时荧光反转录聚合酶链反应, 病原学监测, 多病原监测

Abstract:

Objective To analyze the epidemiological characteristics and monitoring changes of influenza in Jinnan District of Tianjin City from 2018 to 2023，and scientifically prevent and control influenza. Methods The influenza-like-illness（ILI） cases were monitored at influenza surveillance sentinel hospital of Jinnan District of Tianjin（Tianjin Jinnan Hospital） from 2018 to 2023，the real-time fluorescent reverse transcription polymerase chain reaction（RT-PCR） pathogen detection was performed，and the data were analyzed. Results From 2018 to 2023，a total of 57 161 ILI cases were monitored，accounting for 4.23%（57 161/1 350 682） of outpatient and emergency treatment cases. The proportion of ILI cases in 2023 was the highest（7.92%，23 144/292 322），and that in 2021 was the lowest（2.23%，5 414/242 285）. There was statistically significant difference in the proportion of ILI cases among different years（P<0.05）. The pathogenic detection of influenza virus nucleic acid was carried out in 4 109 cases of ILI，and the positive detection rate was 25.33%（1 041/4 109），with statistical difference in annual positive detection rate（P<0.05），and the highest positive detection rate was 42.44%（320/754） in 2019. From 2018 to 2023，the difference of positive detection rate among different age groups was statistically significant（P<0.05），and the highest positive detection rate was 38.37%（432/1 126） in the age group of 7-<15 years old. The positive detection rate was high in the first quarter and the fourth quarter of each year，which accords with the epidemic law of influenza in winter and spring in northern China. The influenza virus was a cross epidemic of H1N1，seasonal H3N2，Victoria（B-V） and Yamagata（B-Y），with different dominant types in different periods. Conclusions The decrease in the detection rate of influenza virus in Jinnan District of Tianjin City from 2020 to 2022 indicates that public health prevention and control measures have also played a role in blocking the spread of influenza virus. It is necessary to continue to enhance the immunity of preschool children and primary and secondary school students，vigorously promote vaccination，pay attention to the monitoring of multiple pathogens in respiratory syndrome，be wary of mixed infections，and scientifically prevent and control respiratory infectious disease outbreaks.

Key words: Influenza, Influenza-like-illness, Real-time fluorescent reverse transcription polymerase chain reaction, Pathogenic monitoring, Multi pathogen monitoring