GASTROINTESTINAL INFECTIONS: Edited by James A. Platts-MillsUpdates on defining and detecting diarrheagenic Escherichia coli pathotypesJesser, Kelsey J.; Levy, KarenAuthor Information Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington, USA Correspondence to Karen Levy, 4225 Roosevelt Way NE, Seattle, WA 98105, USA. Tel: +1 206 543 6991; e-mail: email@example.com Current Opinion in Infectious Diseases: October 2020 - Volume 33 - Issue 5 - p 372-380 doi: 10.1097/QCO.0000000000000665 Buy Metrics Abstract Purpose of review Several types of Escherichia coli cause acute diarrhea in humans and are responsible for a large burden of disease globally. The purpose of this review is to summarize diarrheagenic Escherichia coli (DEC) pathotype definitions and discuss existing and emerging molecular, genomic, and gut microbiome methods to detect, define, and study DEC pathotypes. Recent findings DEC pathotypes are currently diagnosed by molecular detection of unique virulence genes. However, some pathotypes have defied coherent molecular definitions because of imperfect gene targets, and pathotype categories are complicated by hybrid strains and isolation of pathotypes from asymptomatic individuals. Recent progress toward more efficient, sensitive, and multiplex DEC pathotype detection has been made using emerging PCR-based technologies. Genomics and gut microbiome detection methods continue to advance rapidly and are contributing to a better understanding of DEC pathotype diversity and functional potential. Summary DEC pathotype categorizations and detection methods are useful but imperfect. The implementation of molecular and sequence-based methods and well designed epidemiological studies will continue to advance understanding of DEC pathotypes. Additional emphasis is needed on sequencing DEC genomes from regions of the world where they cause the most disease and from the pathotypes that cause the greatest burden of disease globally. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.