Diverse Reservoirs of Third-Generation Cephalosporin-Resistant Escherichia coli in Guatemala

In Guatemala, there is a significant gap in our understanding of the prevalence of antibiotic resistance across different reservoirs likely to affect human exposures. We conducted a One Health study of produce, poultry, water, and humans within peri-urban and urban Guatemalan markets to characterize the prevalence of third-generation cephalosporin-resistant Escherichia coli (3GCR-EC). We screened a total of 132 samples for 3GCR-EC using selective media. Samples were collected across three markets in Guatemala and included produce (n = 32), public tap water (n = 30), commercial and non-commercial poultry (n = 40), and human fecal matter (n = 30). We measured phenotypic and genotypic resistance using culture-based methods and whole-genome sequencing. Among the 132 samples, 87.1% (n = 115) were positive for E. coli, and 67.4% (n = 43) were positive for 3GCR-EC. After removing duplicates, a total of 40 3GCR-EC isolates were sequenced from commercial chicken carcasses (n = 8), non-commercial chicken carcasses (n = 16), water (n = 4), and human feces (n = 12). Out of 11 unique extended-spectrum beta-lactamase genes, the most prevalent gene was bla_CTX-M-55. There was high clonal diversity, with 32 distinct sequence types (ST) detected. Clinically important pandemic lineages of E. coli were identified: ST10, ST648, and ST410. This study identified a high prevalence of antibiotic resistance across diverse samples within public Guatemalan markets. The frequent detection of 3GCR-EC, their resistance genes, and epidemiologically important lineages of E. coli identified from humans, produce, water, and poultry samples highlight the importance of implementing more extensive surveillance using a One Health approach to develop coordinated strategies to mitigate the spread of antibiotic resistance.