Distribution of phylogroups and antibiotic resistance patterns of ESBL-producing Escherichia coli strains isolated from chicken meat in Tamaulipas, Mexico.

In the food industry, one of the main challenges is providing products free from pathogens that cause high morbidity and mortality in consumers. This situation has been further aggravated by the emergence of antibiotic-resistant strains, with some notable examples such as extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC), due to their impact on the healthcare sector, causing difficult-to-treat infections. Therefore, the objective of this study was to evaluate the prevalence of ESBL-EC and their antibiotic resistance patterns in chicken meat sold in Tamaulipas, Mexico. A total of 130 chicken meat samples from 17 municipalities in Tamaulipas were analyzed during 2024. An average prevalence of 20.7% of ESBL-EC was detected. Thirty-eight different antibiotic resistance patterns were identified, and 85.1% were multidrug-resistant (MDR). When classifying the strains into phylogroups, 63.8% were considered commensal (groups A and B1) and 36.1% pathogenic (groups B2 and D). The results of this study demonstrate the presence of pathogenic MDR ESBL-EC strains in chicken meat sold in Tamaulipas, suggesting possible improper handling of this meat, which may pose a risk to consumers. These results also emphasize the need to monitor the presence of antibiotic resistant strains in chicken meat and other foods sold in Mexico.