Novel <i>Salmonella</i> allelic profile and assigned ST.

Salmonella enterica and Escherichia coli are well-known bacteria commonly associated with foodborne illnesses in humans and animals. Genomic characterization of these pathogens provides valuable insights into their evolution, virulence factors and resistance determinants. This study aimed to characterized previously isolated Salmonella (n = 14) and E. coli (n = 19) from milk, meat and its associated utensils in Ghana using whole-genome sequencing. Most of the Salmonella serovars (Fresno, Plymouth, Infantis, Give and Orleans) identified in this study are yet to be reported in Ghana. Most Salmonella isolates were pan-sensitive, but genes conferring resistance to fosfomycin (fosA7.2) and tetracycline (tet(A)) were detected in one and three isolates, respectively. Seven of the Salmonella isolates carried the IncI1-I(Gamma) plasmid replicon. Although antimicrobial resistance was not common among Salmonella strains, most (11/19) of the E. coli strains had at least one resistance gene, with nearly half (8/19) being multidrug resistant and carried plasmids. Three of the 19 E. coli strains belonged to serovars commonly associated with enteroaggregative E. coli (EAEC) pathotype. While strains belonging to virulence-associated lineages lacked key plasmid-encoded virulence plasmids, several plasmid replicons were detected in most of the E. coli (14/19) strains. Food contaminated with these pathogens can serve as a vehicle for disease transmission, posing a significant public health risk and necessitating stringent food safety and hygiene practices to prevent outbreaks. Hence, there is need for continuous surveillance and preventive measures to stop the spread of foodborne pathogens and reduce the risk of associated illnesses in Ghana.肠炎沙门氏菌（Salmonella enterica）与大肠埃希氏菌（Escherichia coli）是广为人知的病原菌，常与人类及动物的食源性疾病（foodborne illnesses）相关。对这类病原菌开展基因组特征解析（genomic characterization），可为其进化过程、毒力因子（virulence factors）及耐药决定因子（resistance determinants）的研究提供宝贵见解。本研究旨在利用全基因组测序（whole-genome sequencing）技术，对此前从加纳乳制品、肉类及其相关器具中分离得到的14株沙门氏菌及19株大肠埃希氏菌进行分析。本研究中鉴定出的多数沙门氏菌血清型（Salmonella serovars）（Fresno、Plymouth、Infantis、Give及Orleans）在加纳尚未见报道。大部分沙门氏菌分离株呈现全敏感表型（pan-sensitive），但分别有1株和3株分离株携带赋予磷霉素（fosfomycin）耐药的fosA7.2基因以及四环素（tetracycline）耐药的tet(A)基因。7株沙门氏菌分离株携带IncI1-I(Gamma)型质粒复制子（plasmid replicon）。尽管沙门氏菌菌株的抗菌药物耐药性（antimicrobial resistance）并不常见，但19株大肠埃希氏菌中的多数（11/19）至少携带1种耐药基因，其中近半数（8/19）为多重耐药（multidrug resistant）菌株且携带质粒。19株大肠埃希氏菌中有3株属于与肠聚集性大肠埃希氏菌（enteroaggregative E. coli，EAEC）致病型（pathotype）相关的常见血清型。尽管携带毒力相关谱系的菌株缺乏关键的质粒编码毒力质粒，但多数大肠埃希氏菌菌株（14/19）中检测到多种质粒复制子。被这些病原菌污染的食物可作为疾病传播媒介，构成显著的公共健康风险（public health risk），因此需实施严格的食品安全与卫生操作以防范暴发疫情。故此，加纳需要开展持续监测（continuous surveillance）与预防措施，阻断食源性病原菌的传播，降低相关疾病的发病风险。