【摘要】 目的 分析呼和浩特市腹泻病例沙门菌的全基因组特征，为沙门菌感染防控和临床合理用药提供依据。方法从2021—2023年呼和浩特市国家食源性疾病监测哨点医院门诊的急性腹泻病例粪便标本中分离并鉴定沙门菌，提取DNA进行全基因组测序。基于Microobench病原微生物基因组分析系统，采用生物信息学方法分析沙门菌的血清型、多位点序列分型、耐药基因和毒力基因；通过NCBI Genome数据库下载60株来自我国各地的沙门菌序列，基于核心基因组多位点序列分型构建系统发育树，分析呼和浩特市与全国菌株的系统发育关系。结果 2021—2023年呼和浩特市42株沙门菌涵盖12种血清型，ST11型肠炎沙门菌、ST34型沙门菌I 4,[5],12:i:-和ST19型鼠伤寒沙门菌是优势菌株，分别为13、10和6株，占30.95%、23.81%和14.29%。检测到12类77种耐药基因，17株沙门菌氟喹诺酮类耐药基因决定区存在gyrA和parC位点突变导致的氨基酸替换。毒力基因覆盖沙门菌致病性全过程，与附着相关的毒力基因较多。系统发育树分析结果显示，呼和浩特市42株沙门菌分散在A、B、C、D和F进化分支中，与全国60株沙门菌聚类，存在跨地区传播的可能。结论 呼和浩特市沙门菌血清型多样，携带多种耐药基因和毒力基因，具有高度的遗传多样性，存在跨区域传播风险，需加大监测与防控力度。更多还原

【Abstract】 Objective To analyze the whole genome characteristics of Salmonella in diarrhea cases in Hohhot City, so as to provide the evidence for the prevention and control of Salmonella infection and rational clinical use of antibiotics.Methods Salmonellastrains were isolated and identified from fecal specimens of acute diarrhea cases at sentinel hospitals for national foodborne disease surveillance in Hohhot City from 2021 to 2023. DNA was extracted for whole genome sequencing. Bioinformatics analysis based on the Microobench Pathogen Genome Analysis System was conducted to determine serotypes, multi-locus sequence typing(MLST), drug resistance genes, and virulence genes. Additionally,60 Salmonella genomic sequences from different regions across China were downloaded from the NCBI Genome database. A phylogenetic tree was constructed based on core-genome MLST(cgMLST) to analyze the phylogenetic relationship between strains from Hohhot City and those from other regions of China.ResultsFrom 2021 to 2023, a total of42 Salmonella strains isolated in Hohhot City were classified into 12 serotypes. Salmonella Enteritidis ST11, Salmonella I 4,[5],12:i:-ST34, and Salmonella Typhimurium ST19 were identified as the dominant strains, represented by 13, 10,and 6 isolates, which accounted for 30.95%, 23.81%, and 14.29%, respectively. Seventy-seven drug resistance genes belonging to 12 classes were detected. Among them, 17 Salmonella strains carried amino acid substitutions in the fluoroquinolone resistance-determining region caused by mutations at the gyrA and parC loci. Virulence genes covered all stages of Salmonella pathogenesis, with a predominance of genes associated with adhesion. Phylogenetic tree analysis results revealed that the 42 Salmonella strains from Hohhot City were distributed across evolutionary branches A, B, C,D, and F. They clustered with 60 strains from other regions of China, suggesting potential cross-regional transmission.Conclusions Salmonellastrains isolated in Hohhot City exhibited diverse serotypes, carried multiple drug resistance genes and virulence genes, and displayed high genetic diversity. These findings indicate a potential risk of cross-regional transmission, highlighting the need for enhanced surveillance and prevention measures.更多还原