[Analysis of pathogenic characteristics in cases of hepangina in sentinel hospitals in Yancheng City from 2023 to 2024].

To understand the composition, prevalence, and evolutionary characteristics of enterovirus pathogens in hepangina cases from sentinel hospitals in Yancheng City from 2023 to 2024, and to analyze the characteristics of the VP1 genes of the identified enteroviruses, molecular typing was performed using real-time fluorescence RT-PCR and nested PCR combined with Sanger sequencing. Bioinformatics software was used to analyze the nucleotide sequences, amino acid sites, and phylogenetic trees of the VP1 genes of the typed enteroviruses. From 2023 to 2024, a total of 86 out of 288 hepangina cases in Yancheng City tested positive for enterovirus nucleic acid, yielding a positive detection rate of 29.86%. This study identified five enterovirus types: CVA4, CVA6, CVA10, CVA5, and CVA16. Their respective positive detection rates were 12.50% (36/288), 9.38% (27/288), 3.82% (11/288), 2.08% (6/288), and 2.08% (6/288). Phylogenetic analysis showed that the Yancheng strains of CVA4, CVA6, CVA10, CVA5, and CVA16 belonged to the C2, D3a, C2, C1, and B1b/B1a gene subtype evolutionary branches, respectively.In 2023, the predominant enterovirus types were CVA6, CVA10, and CVA16, with positive detection rates of 18.75% (27/144), 4.17% (6/144), and 4.17% (6/144), respectively. In 2024, the predominant types shifted to CVA4, CVA5, and CVA10, with positive detection rates of 23.61% (34/144), 3.47% (5/144), and 3.47% (5/144), respectively.