Microbial dynamics and the prevalence of foodborne pathogenic bacteria in sediments of Conococheague creek, Pennsylvania

Authors: BOOMER, ASHLEY - US Department Of Agriculture (USDA); YIN, HSINBAI - US Department Of Agriculture (USDA); CHEN, CHI-HUNG - US Department Of Agriculture (USDA); HARRIGER, DANA - Wilson College; Patel, Jitu

Submitted to: Institute of Food Technology
Publication Type: Abstract Only
Publication Acceptance Date: 3/26/2021
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Introduction: Bed sediments may contain bacterial pathogens and these microbial contaminants could be resuspended into water body. Investigation of microbial contamination in sediments represent valuable inputs in predicting the microbial quality of water. Methods: The objective of this study was to determine the populations of fecal indicator bacteria and the prevalence of pathogenic bacteria including Salmonella, E. coli O157:H7, and Listeria monocytogenes in sediments of Conococheague creek, PA. Sediment samples (n=378) were collected every week from 3 different sites along the Conococheague creek, PA during July 2019-December-2020. The samples (10g) were mixed with 30-ml buffer peptone water, .hand-massaged for 1 min and then sonicated for 2 min, followed by plating on VRB, mFC, and TBX agar plates for enumerations of total coliforms, fecal coliforms, and generic E. coli, respectively, or enriched to detect the presence Salmonella, E. coli O157:H7, and L. monocytogenes by real-time quantitative PCR. Moisture content of each sediment sample was measured, and the bacterial populations were expressed as log CFU/g dry weight. Results: An average of 3.4-3.6 log, 2.4-2.8 log, and 1.3-2.0 log CFU/g of total coliforms, fecal coliforms, and generic E. coli was recovered from the sediment samples collected during this period. Populations of total coliforms and fecal coliforms were stable throughout the entire collection period; however, generic E. coli populations were affected by the season. E. coli populations were lower during winter (1.3 log CFU/g);) as compared to summer season (2.0 log CFU/g). There was no co-relation between the populations of indicator bacteria and the presence of bacterial pathogens. The prevalence of Salmonella, E. coli O157:H7, and L. monocytogenes was at 4.2%, 4.2%, and 17.4%, respectively. Significance: The information about the microbial dynamics in the sediments of Conococheague creek, PA and is helpful to farmers using the creek water for irrigation. The data can be used in modelling to predict microbial quality of creek water.