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The European Food Safety Authority (EFSA) identified extended-spectrum β-lactamase/AmpC β-lactamase (ESBL/AmpC)-producing E. coli as one of the main priority hazards for poultry. Different studies detected ESBL-producing E. coli at broiler fattening farms and in abattoirs, concluding that poultry meat is a potential source of human infection. Broiler breast skin samples taken in three abattoirs with different scalding techniques were examined for ESBL-producing Escherichia (E.) coli and their phylogenetic groups. A total of 307 ESBL-producing E. coli isolates were found, and the abattoir with conventional immersion scalding with thermal treatment of the water had the lowest incidence. Phylogroups D/E and B1 were mostly detected, while phylogroups C, D, and E were not detected. Phylogroup B2 was detected in low proportions. The phylogroups B2 and D are important as they have been associated with urinary tract infections in humans, but were only detected in low proportions at different processing stages in this study. Since the risk for the consumer of being infected via chicken meat with ESBL-producing E. coli and E. coli of highly pathogenic phylogroups cannot be excluded, good kitchen hygiene is of great importance. [ABSTRACT FROM AUTHOR]

Food is often contaminated with Escherichia coli (E. coli) bacteria strains, which have been associated with different diseases, including urinary tract infections. The consumption of meat by humans is a potential route of transmission of antimicrobial resistance, and food-producing animals have been associated as a major reservoir of resistant bacterial strains. The aim of this study was to determine the presence of the E. coli strains producing the CNF-1 toxin in pig kidneys. Pig kidneys were collected from a Mexican slaughterhouse and classified according to their coloration into reddish kidneys (RK) and yellowish kidneys (YK). A tissue sample from each kidney was processed for histological analysis, the presence of E. coli was determined by conventional PCR assay, and the CNF-1 toxin was detected by both conventional PCR and Western blotting. Herein, an inflammatory cell infiltrate was found in all collected kidneys, regardless of macroscopic differences. Surprisingly, E. coli and the CNF-1 toxin were detected in all kidney samples. We clearly demonstrate contamination by CNF-1 toxin-producing E. coli in pork kidneys from a slaughterhouse, even in those without apparent damage. This suggests that pork may serve as a reservoir for pathogens, representing an important risk to human health. [ABSTRACT FROM AUTHOR]

Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) is one of the most important foodborne pathogens that infect humans globally. The gastrointestinal tracts of animals like pigs, poultry or cattle are the main reservoirs of Salmonella serotypes. Guinea pig meat is an important protein source for Andean countries, but this animal is commonly infected by S. Typhimurium, producing high mortality rates and generating economic losses. Despite its impact on human health, food security, and economy, there is no genomic information about the S. Typhimurium responsible for the guinea pig infections in Peru. Here, we sequence and characterize 11 S. Typhimurium genomes isolated from guinea pigs from four farms in Lima-Peru. We were able to identify two genetic clusters (HC100_9460 and HC100_9757) distinguishable at the H100 level of the Hierarchical Clustering of Core Genome Multi-Locus Sequence Typing (HierCC-cgMLST) scheme with an average of 608 SNPs of distance. All sequences belonged to sequence type 19 (ST19) and HC100_9460 isolates were typed in silico as monophasic variants (1,4,[5],12:i:-) lacking the fljA and fljB genes. Phylogenomic analysis showed that human isolates from Peru were located within the same genetic clusters as guinea pig isolates, suggesting that these lineages can infect both hosts. We identified a genetic antimicrobial resistance cassette carrying the ant(3)-Ia, dfrA15, qacE, and sul1 genes associated with transposons TnAs3 and IS21 within an IncI1 plasmid in one guinea pig isolate, while antimicrobial resistance genes (ARGs) for β-lactam (blaCTX-M-65) and colistin (mcr-1) resistance were detected in Peruvian human-derived isolates. The presence of a virulence plasmid highly similar to the pSLT plasmid (LT2 reference strain) containing the spvRABCD operon was found in all guinea pig isolates. Finally, seven phage sequences (STGP_Φ1 to STGP_Φ7) were identified in guinea pig isolates, distributed according to the genetic lineage (H50 clusters level) and forming part of the specific gene content of each cluster. This study presents, for the first time, the genomic characteristics of S. Typhimurium isolated from guinea pigs in South America, showing particular diversity and genetic elements (plasmids and prophages) that require special attention and also broader studies in different periods of time and locations to determine their impact on human health. [ABSTRACT FROM AUTHOR]

Livestock animals, especially poultry, are a known reservoir for extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (E. coli). They may enter the pen either via positive day-old chicks or via the environment. We developed a mathematical model to illustrate the entry and dissemination of resistant bacteria in a broiler pen during one fattening period in order to investigate the effectiveness of intervention measures on this infection process. Different management measures, such as varying amounts of litter, a slow-growing breed or lower stocking densities, were tested for their effects on broiler colonization. We also calculated the impact of products that may influence the microbiota in the chicks' digestive tract, such as pre- or probiotics, feed supplements or competitive exclusion products. Our model outcomes show that a contaminated pen or positive chicks at the beginning of the fattening period can infect the entire flock. Increasing the amount of litter and decreasing the stocking density were shown to be effective in our model. Differences in the route of entry were found: if the chicks are already positive, the litter quantity must be increased to at least six times the standard of 1000 g/m2, whereas, if the pen is contaminated on the first day, three times the litter quantity is sufficient. A reduced stocking density of 20 kg/m2 had a significant effect on the incidence of infection only in a previously contaminated pen. Combinations of two or three measures were effective in both scenarios; similarly, feed additives may be beneficial in reducing the growth rate of ESBL-producing E. coli. This model is a valuable tool for evaluating interventions to reduce the transmission and spread of resistant bacteria in broiler houses. However, data are still needed to optimize the model, such as growth rates or survival data of ESBL-producing E. coli in different environments. [ABSTRACT FROM AUTHOR]