Molecular Epidemiological Characteristics of Noroviruses in Outbreaks of Acute Gastroenteritis in Dalian,China,2020-2023
We analyzed the genotype characteristics of noroviruses in 16 outbreaks of acute gastroenteritis(AG)in Dalian,China from 2020 to 2023.A total of 154 fecal specimens from patients with AG in Dalian,China from 2020 to 2023 were collected.Real-time reverse transcription-quantitative polymerase chain reaction(RT-qPCR)was used to detect norovirus GⅠ/GⅡ genogroups.Regions coding for RNA-dependent RNA polymerase and capsid protein VP1 of noroviruses were amplified and sequenced by RT-PCR on positive samples.Norovirus typing was determined through the Norovirus Genotyping Tool and Human Calicivirus Typing Tool,and a phylogenetic tree was constructed using MEGA software.Among all 154 samples,106 were positive for noroviruses.The positive rate for the norovirus GⅠ genogroup was 3.77％(4/106),whereas that of the GⅡgenogroup was 96.23％(102/106).Fifteen of the 16 outbreaks were caused by the GⅡ genogroup,one by the GⅠ genogroup,and mixed infection of GⅠGⅡ was not documented.Outbreaks were dominated by the GⅡgenogroup.The main epidemic strain in 2020/2021 and 2022/2023 was GⅡ.2[P16],and there was little variation of this genotype in different years.Multiple genotypes of noroviruses were coexisting in the 2021/2022 epidemic season,with no dominant epidemic strains.The AG outbreaks due to noroviruses in Dalian,China from 2020 to 2023 occurred primarily from November to April,mainly in kindergartens,primary schools and middle schools.
万方数据
维普
