A Comprehensive Review of the Role of Virulence Factors in Enteropathogenic Escherichia coli-Induced Intestinal Injury.

is a rod-shaped gram-negative bacterium that includes the diarrheagenic strains, an identical group of intestinal pathogens. diarrhea is transmitted through the feco-oral route, through contaminated food and water. (EPEC)is one of the leading causes of diarrhea in the pediatric age group in developing and developed countries. Depending on the absence or presence of adherence factor plasmids, they are classified as typical or atypical isolates. The distinguishing feature of EPEC's pathology is the attaching and effacing lesions, which facilitate localized damage by tightly adhering to intestinal epithelial cells, disarranging their surfaces, and effacing microvilli. Typical EPEC possess the locus of enterocyte effacement (LEE), a pathogenicity island, encoding adherence factors, including the Type III Secretion System (T3SS), a needle-like structure injecting effector proteins into host cells. EPEC also have other effector genes like or encoded by non-LEE pathogenicity islands, which enable destruction of tight junctions in the host cell. Another key virulence factor is bundle-forming pili (BFP), which aids in the first attachment to enterocytes. Methods like quantitative PCR exist to diagnose EPEC accurately. As of today, no licensed vaccine exists to prevent EPEC infections. Virulence factors for attachment, such as bfpA and intimin, and immunogenic carriers can be potential candidates for vaccine development. Moreover, studies are required to better understand the interaction of EPECwith the intestinal microbiome and immune evasion strategies. This article is aimed at providing a comprehensive review of the epidemiology, transmission, virulence factors, challenges in studying EPEC virulence factors, pathogenesis, host-pathogen interaction, mechanism of intestinal injury, diagnosis, treatment, antibiotic resistance, and vaccination strategy for EPEC, and future research implications. We conducted a comprehensive literature search using credible sources such as PubMed, Google Scholar, and Scopus. We refined our keywords, applied database filters, and assessed citations in the included studies. No meta-analysis, statistical aggregation, or formal evaluation of risk bias was carried out as this review consolidates the literature narratively. High-quality English articles published in reputable peer-reviewed journals from 2010 to 2025 were analyzed, and their findings have been summarized in this comprehensive review.