Multidrug‐Resistant Outbreak‐Associated Salmonella Strains in Irrigation Water from the Metropolitan Region, Chile

Abstract

Salmonella enterica (S. enterica) is the main cause of foodborne diseases in the Chilean population. With the aim of characterizing the presence of S. enterica in bodies of water, samples from 40 sources were obtained, including rivers and irrigation canals used by agricultural farms in the most populated regions of Chile. As result, 35 S. enterica isolates belonging to several serotypes were detected, with the highest frequency represented by Typhimurium and Enteritidis. All strains showed phenotypic antimicrobial resistance, and most of them were multiresistant to critically important antimicrobials. In addition, the pulse-field gel electrophoresis analysis using XbaI and BlnI endonucleases showed that seven Salmonella isolates belonging to serotypes Typhimurium, Enteritidis and Infantis had identical pulsotypes to outbreak-associated clinical isolates detected in the Chilean population, suggesting a public health risk of water pollution in this region. Among sampling sites, the higher detection rates were observed in rural than urban and peri-urban areas, suggesting that the animal husbandry might contribute for environmental dispersion of this pathogen. Future efforts should address the characterization of cause-and-effect relationship between water contamination and foodborne disease, including the implementation of surveillance programmes to tackle potential risks for both human and animal populations.

First detection and characterization ofSalmonellaspp. in poultry and swine raised in backyard production systems in central Chile

“…These three serovars have been isolated from Chilean watercourse from Metropolitana region, and have been linked to human outbreak-associated clinical isolates, mainly detected from rural areas. This indicates that animal husbandry and particularly BPS might contribute to the dissemination and distribution of this pathogen [15], and has been identified as the most historically important serovars, causing over the 60% of the human clinical cases of foodborne-illnesses in Chile [16]. Less common serovars, S. Hadar, S. Tenessee and S. Kentucky, are similar to the major serovars and have been linked to animals or animal products and associated with human clinical outbreaks [55][56][57].…”

“…Factors such as wide distribution of Salmonella enterica in the environment, its prevalence in the global food chain production and pathogen virulence and adaptability; mean that Salmonella have had major economic impact on public health, estimated at $11·6 billion [11]. Over the last decade, disease outbreaks have increased in Chile, and the rest of the world, [12, 13] along with increased detection of antibiotic-resistant serovars [10, 14, 15], highlighting the impact of Salmonella infections on global public health.…”

Investigation of a Salmonellosis Outbreak Caused by Multidrug Resistant Salmonella Typhimurium in China

“…Outbreaks of S. Typhimurium have occurred throughout the world, and most of them were caused by multidrug resistant S. Typhimurium (Alt et al, 2015;Folster et al, 2017;Martínez et al, 2017). However, there have been only a few studies on outbreaks caused by multidrug resistant S. Typhimurium in China.…”

Screening the Presence of Non-Typhoidal Salmonella in Different Animal Systems and the Assessment of Antimicrobial Resistance

“…Besides, the role of closed production systems—especially in meat production, which is affected by Campylobacter jejuni resistance [ 34 ], and marine-farmed salmon, which are affected by Piscirickettsia salmonis resistance [ 35 ]—should also be considered to control the dissemination of AMR and MDR strains in the environment. Examples of contamination may include the use of watercourses risking vegetable uptake and animal consumption [ 14 ].…”

“…In Chile, the presence of Salmonella strains has been reported in different sources including water used for irrigation [ 14 ], backyard flocks [ 15 ], wild animals [ 16 , 17 , 18 , 19 ] and chicken eggs [ 18 ]. One study depicted a prevalence of MDR Salmonella of 13% in 35 strains obtained from irrigation water [ 14 ]. Additionally, a recent article reported one strain of S. Infantis in a wild owl at a Chilean rehabilitation center, which was not only MDR Salmonella but also an extended-spectrum ß-lactamase producer [ 16 ].…”