Genomic Epidemiology Ofsalmonellainfantis In Ecuador: From Poultry Farms To Human Infections

Salmonella entericais one of the most important foodborne pathogens around the world. In the last years,S.entericaserovar Infantis has become an important emerging pathogen in many countries, often as multidrug resistant clones. To understand the importance ofS. entericain the broiler industry in Ecuador, we performed a study based on phenotypic and WGS data of isolates from poultry farms, chicken carcasses and humans. We showed a high prevalence ofS. entericain poultry farms (41.4%) and chicken carcasses (55.5%), but a low prevalence (1.98%) in human samples.S. Infantis was shown to be the most prevalent serovar with a 98.2, 97.8, and 50% in farms, foods, and humans, respectively, presenting multidrug resistant patterns. All sequencedS. Infantis isolates belonged to ST32. For the first time, a pESI-related megaplasmid was identified in Ecuadorian samples. This plasmid contains genes of antimicrobial resistance, virulence factors, and environmental stress tolerance. Genomic analysis showed a low divergence ofS. Infantis strains in the three analyzed components. The results from this study provide important information about genetic elements that may help understand the molecular epidemiology ofS. Infantis in Ecuador.