ABSTRACT
This chapter provides state-of-the-art overviews on foodborne diseases caused by plesiomonads in relation to their etiology, biology, epidemiology, clinical presentation, pathogenesis, diagnosis, treatment, and prevention. Plesiomonads are rod-shaped, gram-negative, facultative anaerobic, oxidase- and catalase-positive, flagellated bacteria emerging as important effectors in foodborne diseases. Plesiomonas taxonomy remains a matter of debate, as it exhibits striking differential characteristics from other enterobacteria. The plesiomonad lipopolysaccharide structure is unique in its family. Due to their perceived low infection rate in industrialized countries, high percentage of coinfections, and specific isolation protocols, plesiomonads have been historically overlooked when searching for gastroenteric disease sources until several reports in recent years highlighted Plesiomonas as disease-causing microorganisms in both gastrointestinal and extraintestinal complications. Hopefully, the establishment of standardized protocols to test for pathogenicity mechanisms and potential virulence factors, together with the easier detection of plesiomonads without the need to specifically search for them using modern technologies such as polymerase chain reaction (PCR), will help advance our knowledge on pathogen.
