SUPPLEMENTARY INFORMATION TABLE S1. Description of sampling sites within the apple packinghouse. Site ID Site description Inside of small PVC by chemical barrels. N of site #'s 301 and 302 - - - - - - - - - - TABLE S2. Univariablea logistic regression model results explaining the relationship between Listeria isolation in the packinghouse and date of sampling and intervention status (i.e., if the sample was collected before or after increasing the frequency of cleaning and sanitation to twice a weekb) in the current study. Model Variable Log-odds (95% CId) P-value P TABLE S3. Final logistic regression model results explaining the relationship between Listeria positive isolation in the packinghouse and date of sampling when combining historical dataa from the packinghouse with the data collected as part of the current study. Variable Log-odds (95% CIb) P-value 568 Food Protection Trends November/December