Non-O1/Non-O139 Vibrio cholerae-An Underestimated Foodborne Pathogen? An Overview of Its Virulence Genes and Regulatory Systems Involved in Pathogenesis

Abstract

In recent years, the number of foodborne infections with non-O1 and non-O139 Vibrio cholerae (NOVC) has increased worldwide. These have ranged from sporadic infection cases to localized outbreaks. The majority of case reports describe self-limiting gastroenteritis. However, severe gastroenteritis and even cholera-like symptoms have also been described. All reported diarrheal cases can be traced back to the consumption of contaminated seafood. As climate change alters the habitats and distribution patterns of aquatic bacteria, there is a possibility that the number of infections and outbreaks caused by Vibrio spp. will further increase, especially in countries where raw or undercooked seafood is consumed or clean drinking water is lacking. Against this background, this review article focuses on a possible infection pathway and how NOVC can survive in the human host after oral ingestion, colonize intestinal epithelial cells, express virulence factors causing diarrhea, and is excreted by the human host to return to the environment.

Keywords: diarrheal disease; infection pathway; non-O1/non-O139 Vibrio cholerae; regulatory systems; virulence genes.

Figure 1

The map of virulence-associated genes and regulatory systems in NOVC: positive relationships are labeled with red arrows and negative relationships are labeled with blue arrows. The whole infection procedure is separated into five stages. Stage 1: survival in host gastrointestinal tract (in orange); stage 2: localization and penetration of the mucus layer in the small intestine (in purple); stage 3: intestinal epithelial cell colonization (in green); stage 4: virulence gene expression (in red); stage 5: detachment from the epithelial cells to return in the environment (in blue). The detailed information is shown in Table S1 in the Supplementary Files.