title: Effects of transparent exopolymer particles and suspended particles on the survival of Salmonella enterica serovar Typhimurium in seawater.
abstract: The bacterium Salmonella enterica can infect marine mammals and has been increasingly implicated in seafood-borne disease outbreaks in humans. Despite the risk this zoonotic agent poses to animals and people, little is known regarding the environmental factors that affect its persistence in the sea. The goal of this study was to evaluate the impact of two constituents on the survival of Salmonella in the marine environment: transparent exopolymer particles (TEP) and suspended particles. A decay experiment was conducted by spiking Salmonella into bottles containing seawater, seawater with alginic acid as a source of TEP, filtered seawater or filtered seawater with alginic acid. Survival of Salmonella was monitored using culture followed by enrichment assays to evaluate if the bacteria entered a viable but non-cultivable (VBNC) state. Salmonella cell counts dropped significantly faster (P ≤ 0.05) in the unfiltered seawater samples with and without TEP. The slowest decay occurred in filtered seawater containing alginic acid, with VBNC Salmonella persisting for 17 months. These findings suggest that TEP may favor Salmonella survival while suspended particles facilitate its decay. Insight on the survival of allochthonous, zoonotic pathogens in seawater can guide monitoring, management and policy decisions relevant to wildlife and human public health.
authors.affiliation: Ecole nationale vétérinaire d'Alfort, 7 Avenue du Général de Gaulle, 94704 Maisons-Alfort Cedex, France.
authors.forename: Marion C F
authors.initials: MC
authors.lastname: Davidson
authors.affiliation: Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California Davis, One Shields Ave. Davis, CA 95616, USA.
authors.forename: Terra
authors.initials: T
authors.lastname: Berardi
authors.affiliation: Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California Davis, One Shields Ave. Davis, CA 95616, USA.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Aguilar
authors.affiliation: Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California Davis, One Shields Ave. Davis, CA 95616, USA.
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Byrne
authors.affiliation: Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California Davis, One Shields Ave. Davis, CA 95616, USA kshapiro@ucdavis.edu.
authors.forename: Karen
authors.initials: K
authors.lastname: Shapiro
mesh_terms: D000464:Alginates / Q000494:pharmacology; D000818:Animals; D020723:Glucuronic Acid / Q000494:pharmacology; D006603:Hexuronic Acids / Q000494:pharmacology; D009792:Oceans and Seas; D011108:Polymers / Q000494:pharmacology; D012486:Salmonella typhimurium / Q000187:drug effects / Q000254:growth & development*; D012623:Seawater / Q000382:microbiology*; D013535:Suspensions
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D011108:Polymers; D013535:Suspensions; D020723:Glucuronic Acid
keywords: Escherichia coli; Salmonella enterica; detection; fecal indicator bacteria; ocean; persistence