Human Gastroenteritis Outbreak Associated with Escherichia albertii, Japan

Tadasuke Ooka, Eisuke Tokuoka, Masato Furukawa, Tetsuya Nagamura, Yoshitoshi Ogura, Kokichi Arisawa, Seiya Harada, and Tetsuya Hayashi

Author affiliations: Author affiliations: University of Miyazaki, Miyazaki, Japan (T. Ooka, Y. Ogura, T. Hayashi); Kumamoto Prefectural Institute of Public Health and Environmental Science, Kumamoto, Japan (E. Tokuoka, M. Furukawa, T. Nagamura, S. Harada); University of Tokushima, Tokushima, Japan (K. Arisawa)

Abstract

Although Escherichia albertii is an emerging intestinal pathogen, it has been associated only with sporadic human infections. In this study, we determined that a human gastroenteritis outbreak at a restaurant in Japan had E. albertii as the major causative agent.

Escherichia albertii is an emerging human and bird pathogen that belongs to the attaching and effacing group of pathogens. This group of pathogens forms lesions on intestinal epithelial cell surfaces by the combined action of intimin, an eae gene–encoded outer membrane protein, and type III secretion system effectors (1–4).
Recently, we found that E. albertii represents a substantial proportion of the strains that had previously been identified as eae-positive Escherichia coli, enteropathogenic E. coli or enterohemorrhagic E. coli; 26 of the 179 eae-positive strains analyzed were found to be E. albertii (5). Furthermore, E. albertii is also a potential Shiga toxin 2f (Stx2f)–producing bacterial species (5). However, no E. albertii–associated gastroenteritis outbreak has been reported, which generates doubts regarding the clinical role of this microorganism. In this study, we revisited an outbreak of gastroenteritis that was presumed to have been caused by eae-positive atypical E. coli OUT:HNM (6) to determine if it was actually caused by E. albertii.