Whole genome sequencing (WGS) analyses have revealed pervasive Listeria monocytogenes strains to be an issue throughout the Norwegian food system, and researchers hypothesize that genetics may factor into which strains survive and spread in food production environments. 

The U.S. Department of Agriculture’s Food Safety and Inspection Service (USDA’s FSIS) has reviewed its investigation of a 2018–2019 foodborne illness outbreak involving chicken contaminated by a multi-drug resistant Salmonella Infantis strain, which was the first time that FSIS identified a strain as “persistent.”