Approach to Epidemiological Mechanism of Infection or Colonization of Egg-Laying Chicken Farms by Salmonella enterica Serovar Enteritidis (SE) Becoming the Main Source of Contamination in Food Poisoning (Review)

Abstract

Salmonella enterica serovar Enteritidis (SE)-induced diarrhea in humans is the typical non-typhoid diarrhea. It develops acutely or subacutely and may be fatal. In this study, the authors focused on difference of molecular expression for farm-isolated SEs. That is because recent studies have demonstrated that O-antigen enlargement may be related to pathogenicity in mice as well as 22-kDa polypeptide-expression (SEp22). They have discovered that many SE strains isolated from chicken farms do not express SEp22, and a deficiency or decreased level of cellular antigen 0 - 12 in SE strains isolated from chicken farms was clarified in a report. Additionally, SEp22 was deficient in SE strains passaged through chickens, whereas, SEp22 was expressed at a high level in SE strains passaged through mice. These findings suggest that SE infection and retention more effectively occur in layer farms than in other animal maintenance environments, which may be a basis of the epidemiological hypothesis to explain the high-level production of SE-contaminated eggs.