Geographic distribution, genetic diversity, and virulence determinants of Shiga toxin-producing Escherichia coli: a descriptive review of the retrieved literature

Abstract Shiga toxin-producing Escherichia coli (STEC) is an important foodborne pathogen associated with a wide range of clinical manifestations, from mild gastroenteritis to severe disease. This study aimed to synthesize the evidence retrieved on the reported occurrence and geographic distribution of STEC across different matrices, as well as their genetic diversity, virulence determinants, clinical manifestations, and antimicrobial resistance profiles. A descriptive, non-exhaustive review was conducted based on studies published between 2010 and 2025, resulting in the inclusion of 55 articles after application of the eligibility criteria. The included studies originated from different geographic regions, although the evidence was markedly concentrated in the Americas, particularly Brazil. STEC was investigated across human, animal, food, and environmental sources. Within the retrieved literature, stx2 and stx1 were widely reported, and stx2a , stx2c , and stx2d were among the recurrently reported stx2 subtypes. O157 and non-O157 STEC were both represented across the included studies. These findings describe reporting patterns within the retrieved literature and should not be interpreted as frequencies of occurrence among studies specifically testing each characteristic or as prevalence among STEC isolates. The included studies also reported diverse sequence types and additional virulence determinants, including eae and ehxA . Clinical information was available in only a subset of studies and included manifestations ranging from diarrhea and bloody diarrhea to hemolytic uremic syndrome (HUS). Antimicrobial resistance was investigated in a subset of the included studies using phenotypic and/or genotypic approaches. Resistance phenotypes and resistance-associated genetic determinants were reported among STEC isolates in different study populations; however, heterogeneity in analytical populations, antimicrobial panels, testing methods, and reporting approaches precluded overall or pooled estimates of antimicrobial resistance. Overall, the findings highlight the diversity of STEC reported across different sources and geographic settings and reinforce the importance of integrated molecular and epidemiological approaches within a One Health framework.