| Congresso Brasileiro de Microbiologia 2023 | Resumo: 454-1 | ||||
Resumo:The production of broilers in Brazil has increased in recent years, leading to health challenges in the poultry industry. Chicken meat and its derivatives are the main foods associated with salmonellosis outbreaks, among the most important causes of foodborne illness worldwide. One of the most common serotypes of Salmonella enterica subsp. enterica isolated in poultry is the serotype Heidelberg (Salmonella Heidelberg), which is also associated with human disease. Constant surveillance systems and assessment of risks associated with environmental sources and antimicrobial resistance dissemination routes are essential to adopt appropriate control measures. This study characterized 13 S. Heidelberg strains isolated from the production chain of pre-slaughter broiler chickens (between 2019 and 2020 in eight Brazilian cities) by whole genome sequencing. The genomes belonged to ST15 and carried a high rate of genes encoding resistance to aminoglycoside (13/13; 100%), fosfomycin (13/13; 100%), sulfonamide (12/13; 92.3%), and tetracycline (12/13; 92.3%). The gene blaCMY-2, encoding resistance to betalactams, was found in 7/13 (54%) genomes. Additionally, the gene qacH associated with resistance to quaternary ammonium compounds, was identified in all genomes. In contrast, the gene sugE, also associated with this type of resistance, was found in 7/13 (54%) genomes. Six Salmonella Pathogenicity Islands and over 100 genes encoding virulence factors were identified associated with the bacteria’s cell adhesion, invasion, and intracellular survival. Mobile genetic elements were also identified, including plasmids carrying antimicrobial- and sanitizer-resistance genes and genes encoding virulence factors, suggesting a risk of dissemination to other bacteria. The analysis of Single Nucleotide Polymorphisms in the core genomes suggests a proximal phylogenetic relationship among some isolates, which can be used to study outbreaks. The next phase of the study aims to perform microbiological risk assessment since genomic analysis revealed the presence of resistance and virulence genes with potential for dissemination. This study adds to our understanding of the Salmonella strains associated with antimicrobial and sanitizer resistance and instigates future regulatory discussions on pathogenic Salmonella in poultry. Palavras-chave: antimicrobial resistance, chicken production chain, food pathogen, food safety, one health Agência de fomento:Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) | |||||