Sequence Types and Antimicrobial Resistance Profiles of <i>Salmonella</i> Typhimurium in the Food Chain in Singapore

Abstract

Salmonella remains a significant foodborne pathogen globally with S. Typhimurium presenting as a frequently occurring serovar. This study aimed to characterize 67 S. Typhimurium isolates from humans, food, farms, and slaughterhouses collected in Singapore from 2016 to 2017. Using whole-genome sequencing analysis, the isolates were found to belong to either ST19 (n = 33) or ST36 (n = 34). ST36 predominated in human intestinal and chicken isolates, while human extra-intestinal and non-chicken food isolates belonged to ST19. Plasmids were predicted in 88.1% (n = 59) of the isolates with the most common incompatibility group profiles being IncFIB(S), IncFII(S) and IncQ1. IncFIB(S) (adjusted p-value p-value p-value S. Typhimurium isolates in Singapore, informing strategies for future public health and food safety surveillance.

Keywords

• <i>Salmonella</i> Typhimurium
• antimicrobial resistance
• salmonellosis
• surveillance
• food
• human