Tracing the Origins of Salmonella Outbreaks

Abstract

Salmonellosis is a serious illness transmitted by various serotypes of the Salmonella bacteria that are present as contaminants in chicken carcasses, eggs, and egg products. In a Perspective, Bäumler and colleagues put forward the hypothesis that the increased incidence of food-borne Salmonella since the late 1960s is due to the emergence of one particular serotype, S. enteritidis, as a major poultry-associated pathogen. Through retrospective analysis of epidemiological data on the prevalence of Salmonella pathogens in humans and poultry, the authors propose that the culling of poultry infected with two related Salmonella serotypes (that carry a common antigen, O9) depleted flock immunity, enabling S. enteritidis to fill the niche left behind by the elimination of the avian pathogens.