Julie Dagenais Brian A. Stacy Jason T. Ladner Jeffrey M. Lorch George H. Balazs Elias Barquero-Calvo Brenda M. Berlowski-Zier Renee Breeden Natalia Corrales-Gomez Rocio Gonzalez-Barrientos Heather Harris Gabriela Hernandez-Mora Angel Herrera-Ulloa Shoreh Hesami T. Todd Jones Juan Alberto Morales Terry M. Norton Robert Rameyer Daniel Taylor Thomas B. Waltzek Thierry M. Work 2019 <p><i>Salmonella</i> spp. are frequently shed by wildlife including turtles, but <i>S. enterica</i> subsp. <i>enterica</i> serovar Typhimurium or lesions associated with <i>Salmonella</i> are rare in turtles. Between 1996 and 2016, we necropsied 127 apparently healthy pelagic olive ridley turtles (<i>Lepidochelys olivacea</i>) that died from drowning bycatch in fisheries and 44 live or freshly dead stranded turtles from the west coast of North and Central America and Hawaii. Seven % (9/127) of pelagic and 47% (21/44) of stranded turtles had renal granulomas associated with S. Typhimurium. Stranded animals were 12 times more likely than pelagic animals to have <i>Salmonella</i>-induced nephritis suggesting that <i>Salmonella</i> may have been a contributing cause of stranding. S. Typhimurium was the only <i>Salmonella</i> serovar detected in <i>L. olivacea</i>, and phylogenetic analysis from whole genome sequencing showed that the isolates from <i>L. olivacea</i> formed a single clade distinct from other S. Typhimurium. Molecular clock analysis revealed that this novel clade may have originated as recently as a few decades ago. The phylogenetic lineage leading to this group is enriched for non-synonymous changes within the genomic area of Salmonella pathogenicity island 1 suggesting that these genes are important for host adaptation.</p> application/pdf 10.1038/s41598-019-45752-5 en Springer Nature A novel host-adapted strain of Salmonella Typhimurium causes disease in olive ridley turtles (Lepidochelys olivacea) in the Pacific. article