UNASSIGNED: Samples were obtained from 27 patients of 96 cases, as well as samples of contaminated food in Macau. The collected samples were subjected to serological identification, drug sensitivity analysis, drug resistance gene identification, virulence factor analysis, and tracing.
UNASSIGNED: Twenty-six isolates and the salad isolate were S. enteritidis ST11. Isolates from patients were exhibited significant resistance to Penicillin AMP (Ampicillin) and quinolones NAL (Nalidixic acid). Among these isolates, 21 strains were resistant to two or more antibiotics, indicating the multi-drug resistance (MDR). Genomic characteristics and phylogenetic analysis were performed on 9 of the isolates using whole genome sequencing (WGS). The analysis revealed that the resistance to AMP and NAL was primarily caused by a gryA mutation D87Y (9/9, 100%), and the presence of beta-lactam resistance genes blaOXA-1 (1/9, 11.11%), blaTEM-141 (1/9, 11.11%), and blaTEM-1B (8/9, 88.89%). It was also found a strains isolated from patients had two resistance genes to quinolones or beta-lactam drugs (1/8, 12.5%), respectively. The strains were found to possess 165 virulence genes, one adherence class virulence factor, one invasion class virulence factor and various pathogenicity islands, including SPI-1, SPI-2, SPI-3, SPI-4, SPI-5, SPI-9, SPI-10, SPI-13, SPI-14, SPI-15, SGI 1, CS54_island, and C63PI-1. Additionally, the virulence plasmids were detected, including IncFIB(s)-IncFII(s)-IncX1 (55.56%), IncFIB(s)-IncFII(s) (33.33%), and IncFIB(s)-IncFII(s)-IncHI2-IncHI2A (11.11%). PFGE (Pulsed Field Gel Electrophoresis) and phylogenetic tree analysis revealed a high degree of similarity between Salmonella isolates from patients and food samples from Macao.
UNASSIGNED: This study identified Salmonella enterica ST11 as the cause of the food poisoning outbreak. The findings highlight the importance of phenotypic characterization and next-generation sequencing (NGS) tools in epidemiological studies and emphasize the potential risk of a new emerging multi-antibiotic ST11 clone for S. enteritidis.
■样本来自96例患者中的27例,以及澳门受污染食品的样本。对采集的样品进行血清学鉴定,药物敏感性分析,耐药基因鉴定,毒力因子分析,和追踪。
■26个分离株和沙拉分离株是肠炎沙门氏菌ST11。患者的分离株对青霉素AMP(氨苄西林)和喹诺酮NAL(萘啶酸)表现出明显的耐药性。在这些分离物中,21株对两种或两种以上抗生素耐药,表明多药耐药(MDR)。使用全基因组测序(WGS)对9个分离株进行了基因组特征和系统发育分析。分析表明,对AMP和NAL的抗性主要是由GryA突变D87Y(9/9,100%)引起的,β-内酰胺抗性基因blaOXA-1的存在(1/9,11.11%),blaTEM-141(1/9,11.11%),和blaTEM-1B(8/9,88.89%)。还发现从患者中分离出的菌株对喹诺酮类药物或β-内酰胺类药物有两个耐药基因(1/8,12.5%),分别。发现这些菌株具有165个毒力基因,一种粘附类毒力因子,一种入侵类毒力因子和各种致病性岛,包括SPI-1、SPI-2、SPI-3、SPI-4、SPI-5、SPI-9、SPI-10、SPI-13、SPI-14、SPI-15、SGI1、CS54_island、和C63PI-1。此外,检测到毒力质粒,包括IncFIB(s)-IncFII(s)-IncX1(55.56%),IncFIB(s)-IncFII(s)(33.33%),和IncFIB(s)-IncFII(s)-IncHI2-IncHI2A(11.11%)。PFGE(脉冲场凝胶电泳)和系统发育树分析显示,患者的沙门氏菌分离株与澳门的食物样品之间存在高度相似性。
■这项研究确定了肠道沙门氏菌ST11是食物中毒爆发的原因。研究结果强调了表型表征和下一代测序(NGS)工具在流行病学研究中的重要性,并强调了新出现的多抗生素ST11克隆对肠炎沙门氏菌的潜在风险。