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Genomic characterisation of Salmonella enterica serovar Wangata isolates obtained from different sources reveals low genomic diversity.

ABSTRACT: Salmonella enterica serovar Wangata is an important pathogen in New South Wales (NSW), Australia. The incidence of S. Wangata is increasing and transmission is suspected to be via a non-food source. A recent outbreak investigation of sources of S. Wangata recovered isolates from humans, domestic animals, wildlife and the environment. Here, we extend that investigation by characterising and describing the genomic determinates of these isolates. We found that Australian S. Wangata isolates from different sources exhibited similar virulence and antimicrobial resistance gene profiles. There were no major genomic differences between isolates obtained from different geographical regions within Australia or from different host species. In addition, we found evidence (low number of SNPs and identical virulence gene profiles) suggestive of an international transmission event between Australia and the United Kingdom. This study supports the hypothesis that S. Wangata is shared between different hosts in NSW, Australia and provides strong justification for the continued use of genomic surveillance of Salmonella.

SUBMITTER: Simpson KMJ

PROVIDER: S-EPMC7048276 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Genomic characterisation of Salmonella enterica serovar Wangata isolates obtained from different sources reveals low genomic diversity.

Simpson Kelly M J KMJ Mor Siobhan M SM Ward Michael P MP Collins Julie J Flint James J Hill-Cawthorne Grant A GA Abd El Ghany Moataz M

PloS one 20200228 2

Salmonella enterica serovar Wangata is an important pathogen in New South Wales (NSW), Australia. The incidence of S. Wangata is increasing and transmission is suspected to be via a non-food source. A recent outbreak investigation of sources of S. Wangata recovered isolates from humans, domestic animals, wildlife and the environment. Here, we extend that investigation by characterising and describing the genomic determinates of these isolates. We found that Australian S. Wangata isolates from di ...[more]

PMID: 32109266

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Project description:Salmonella enterica serovar Panama, a causative agent of non-typhoidal salmonellosis (NTS), is one of several serovars that causes invasive NTS disease (iNTS) in humans. S. Panama is an understudied pathogen, with its pathobiology poorly understood. It is a predominant iNTS serovar in Australia, a high-income country with high rates of salmonellosis, where S. Panama has been documented to have a high odds ratio (13.9-15.26) for causing iNTS. This study investigates the genomic epidemiology and antimicrobial resistance profiles of all S. Panama isolates recovered in Victoria, Australia, between 2000 and 2021. We examined the infection dynamics of S. Panama in seven isolates, representing the genetic diversity of the study population. Two sub-lineages, encompassed within a previously described Asian lineage, were identified. Multi-drug resistance (resistance to ≥3 drug classes) was detected in 46 (51.7%) Australian isolates. The plasmid-mediated colistin resistance gene, mcr1.1, was detected in one Australian S. Panama isolate, carried by an IncI plasmid previously reported in Salmonella and Escherichia coli isolates collected from poultry in South-East Asia. Examination of the intracellular replication dynamics of S. Panama isolates demonstrated diverse phenotypes. In THP-1 derived macrophages, despite low host cell uptake, S. Panama showed higher replication rates over time compared to S. enterica serovar Typhimurium. However, a causative genotype could not be identified to explain this observed phenotype. This study provides insights into the S. Panama isolates circulating in Australia over two-decades, finding that 78% were linked to international travel suggesting importation in Australia. It shows MDR was common in this iNTS serovar, and colistin resistance reported for the first time. It provides the first data on the host-pathogen interactions of S. Panama in Australia, which will aid our collective understanding of the pathobiology of S. Panama and iNTS serovars more broadly.

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Dataset Information

Genomic characterisation of Salmonella enterica serovar Wangata isolates obtained from different sources reveals low genomic diversity.

Publications

Genomic characterisation of Salmonella enterica serovar Wangata isolates obtained from different sources reveals low genomic diversity.

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