A Big Step Forward in Tracing Foodborne Illness Back to Its Source

Where pulsed-field gel electrophoresis failed to distinguish a strain of Salmonella enterica responsible for a major salmonellosis 2009-2010 outbreak from a strain isolated in a prior separate outbreak so-called next-gen DNA sequencing (NGS) has allowed researchers to pinpoint the source of the recent outbreak to a specific spice used on salami. SeeIdentification of a Salmonellosis Outbreak by Means of Molecular Sequencing. Note however that traditional epidemiologic traceback techniques had lead investigators to the source of the outbreak. NGS confirmed the outbreak and further demonstrated that endemic contamination of food facilities by pathogens can lead to the production of new strains thereby making more precise sequencing "essential to the traceback of bacterial pathogens as they emerge in the food supply."