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ARS Home » Midwest Area » Bowling Green, Kentucky » Food Animal Environmental Systems Research » Research » Publications at this Location » Publication #391198

Research Project: Developing Agronomically and Environmentally Beneficial Management Practices to Increase the Sustainability and Safety of Animal Manure Utilization

Location: Food Animal Environmental Systems Research

Title: Dynamics, serotypes, and antimicrobial resistance of salmonella in a karst ground water system

item Agga, Getahun
item KAISER, RACHEL - Western Kentucky University
item POLK, JASON - Western Kentucky University
item ALLARD, MARC - Food And Drug Administration(FDA)

Submitted to: International Association for Food Protection
Publication Type: Abstract Only
Publication Acceptance Date: 3/21/2022
Publication Date: 8/1/2022
Citation: Agga, G.E., Kaiser, R., Polk, J., Allard, M. 2022. Dynamics, serotypes, and antimicrobial resistance of salmonella in a karst ground water system. International Association for Food Protection. P1-178.

Interpretive Summary: -

Technical Abstract: Salmonella is the leading cause of bacterial foodborne infections, hospitalizations, and deaths. While over two-thirds of human infections are foodborne, a quarter of cases are acquired from other sources including water. Although most infections are self-limiting, it causes severe infections in certain populations including children, requiring antibiotic treatment. Thus, antimicrobial resistant Salmonella is considered as a serious public health threat by CDC. The purpose of this study was to monitor the dynamics of Salmonella ground water contamination, serotype distribution, and antimicrobial resistance. Ten sites in the city of Bowling Green, Kentucky, were monitored by weekly water sampling over 46 weeks. Water samples were filtered and cultured for the isolation of Salmonella following standard methods. PCR confirmed isolates were whole genome sequenced for serotyping and genotypic resistance. Effects of sampling site, sampling week, month, and season on the prevalence and serotype distribution were analyzed using likelihood ratio test or exact chi-square test, and binary logistic regression. Overall Salmonella prevalence in the ground water samples (n=443) was 14.4%. The prevalence significantly varied by tier category (higher in the top tier sites), sampling sites (range: 3.5-26%), sampling weeks (range: 0-90%), month (range: 0-33%), and by season (range: 1.8-20%). Positive water samples (n=64) resulted in 176 isolates that belonged to 18 serotypes. Prevalence of genotypic resistance was 12.5% (n=176). Majority of the resistant isolates (82%; n=22) were multidrug resistant. Nine antimicrobial resistance genes belonging to aminoglycosides, phosphonic acids, sulfonamides, tetracyclines, and quaternary ammonium compounds were detected. Weekly ground water sampling is important for Salmonella monitoring. Salmonella was widespread among the monitored sites across months and seasons. Antimicrobial resistance was low and limited to few serotypes. The highest prevalence in surface water, main source of drinking water for the city, requires special attention to protect the drinking water supply.