Recent progress on enterotoxigenic E. coli (ETEC) and antibiotic resistance in pathogenic E. coli

Enterotoxigenic Escherichia coli (ETEC) is one of the leading bacterial causes of diarrhea, particularly among children in low-resource settings, travelers, and military personnel from high-income countries. Due to the lack of safe water and sanitation in low-and middle-income countries (LMICs) in Latin America, ETEC is endemic in the region and has a wider range of reservoirs that include One Health-defined settings such as the environment, farm animals, and crops. In the last 10 years, the significant advance in next generation sequencing (NGS) technologies has allowed the study of hundreds of ETEC genomes and revealed that part of the success of ETEC is the large gene and genomic diversity, but also conserved combinations of virulence genes packed in conjugable plasmids and the bacterial chromosome. Advances in knowledge of new virulent genes, microbial pathogenesis, host-pathogen, and microbiome interactions have contributed to the understanding of the various aspects of ETEC infections, as well as in identifying alternative targets for treatment development. Currently, several vaccines are being developed, and the search for targets in ETEC pangenomes will benefit the development of future vaccines with broad coverage, particularly when antibiotic resistance in E. coli and ETEC strains is on the rise.