Serological Variety and Antimicrobial Resistance in Salmonella Isolated from Reptiles

Abstract

Salmonella enterica is one of the best adapted bacterial pathogens causing infections in a wide variety of vertebrate species. The aim of this study was to investigate the prevalence of Salmonella in different reptile species and to evaluate their serological variety and patterns of antimicrobial resistance. In total, 97 samples from 25 wild and domesticated reptile species were investigated in Lithuania. Serological variety, as well as phenotypical and genotypical resistance to antimicrobials, were investigated. Fifty isolates of Salmonella were obtained from the ninety-seven tested samples (51.5%; 95% CI 41.2–61.2). A significantly higher prevalence of Salmonella was detected in domesticated individuals (61.3%; 95% CI 50.0–71.5) compared with wild ones (18.2%; 95% CI 7.3–38.5). All isolates belonged to a single species, Salmonella enterica. Results demonstrated that reptiles carry a large variety of Salmonella serovars. Thirty-four isolates (68%) of Salmonella were resistant to at least one antimicrobial drug. The most frequent resistance of the isolates was to streptomycin (26%), cefoxitin, gentamicin, tetracycline and chloramphenicol (16%). Genes encoding resistance to tetracyclines, aminoglycosides, sulphonamides and trimethoprim were detected. No integrons that are associated with horizontal gene transfer were found. Data obtained provided knowledge about the adaptation of Salmonella in reptiles. Healthy individuals, irrespective of their origin, often carry Salmonella, including multi-resistant strains. Due to its large serological diversity, zoonotic potential and antimicrobial resistance, Salmonella in reptiles poses a risk to other animals and humans.

Surveys on Pet-Reptile-Associated Multi-Drug-Resistant Salmonella spp. in the Timișoara Metropolitan Region—Western Romania

“…The antibiotic resistance of bacteria to antimicrobials is currently a primary concern in both human and veterinary medicine. For this reason, epidemiological studies in domestic and wild animals should be performed on a regular basis [25]. Resistant pathogens, including Salmonella enterica, should be paid particular attention, as these bacteria are very well adapted to different hosts, carry different genes encoding for both virulence and antimicrobial resistance, and are currently among the most common infectious agents isolated from humans with food-borne infections.…”

Molecular Characterization of Salmonella spp. Isolates from Wild Colombian Babilla (Caiman crocodilus fuscus) Isolated In Situ

“…Moreover, in Chile, no reptiles presented the gene [ 43 ]. In reptiles of Poland, Salmonella strains present a frequent resistance to streptomycin (25%; n = 134/533) [ 33 ] as well as reptiles in Lithuania (26%; n = 13/50) [ 24 ]. Nevertheless, in Lithuania the phenotypic resistance is mediated by other genes, such as armA and aadA , that were not evaluated in this study [ 24 ].…”

“…In reptiles of Poland, Salmonella strains present a frequent resistance to streptomycin (25%; n = 134/533) [ 33 ] as well as reptiles in Lithuania (26%; n = 13/50) [ 24 ]. Nevertheless, in Lithuania the phenotypic resistance is mediated by other genes, such as armA and aadA , that were not evaluated in this study [ 24 ]. Likewise, the sul1 gene encoding dihydropteroate synthases, which confer sulfamethoxazole resistance [ 47 ], was detected in the totality of the strains, which differs from reports in the United States, where this gene was not present in wild reptiles [ 46 ].…”

“…Salmonella is considered a public health concern due to different animals that carry the bacteria and have a function as vehicles of transmission, as well as its resistance to multiple antibiotics (MDR) that hinders its treatment [ 4 , 23 ]. Previously, the resistance genes aadA (aminoglycosides), sul2 (sulphonamides), dfr1 , dfr7 (trimethoprim), and tet (A) and tet (B) (tetracyclines), which confer resistance to antibiotics used in humans, have been reported in Salmonella isolated from different species of reptiles [ 24 ]. In waterbodies where wildlife animals live, it has been revealed the antibiotic pollution accumulated in the sediments caused by wastewater from animal farming and hospitals is a problem due to the development of bacteria’s resistance to multiple antibiotics and horizontal gene transfer [ 25 ].…”

Resistance in Enteric Shigella and nontyphoidal Salmonella: emerging concepts

“…It has been confirmed that Salmonella drug resistance is largely driven by the use of antibiotics in food-producing animals in developed countries [6,7]. Additionally, the spread of resistance can occur through direct contact with animals or environmental pathways, such as water or wildlife [8,9].…”