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Patchanee, P.

Publications and source records attributed to Patchanee, P..

6 recordsLinked to original sources

Investigation of swine caecal microbiomes in the northern region of Thailand

IntroductionThe northern region of Thailand serves as a crucial area for swine production, contributing to the global food supply. Previous studies have highlighted the presence of foodborne pathogens originating from swine farms in this region, posing a threat to both human and animal health. Gap statementMultiple swine pathogens have been studied at a species level, but the distribution and co-occurrence of pathogens in agricultural swine has not been well established. AimOur study employed the intestinal scraping technique to directly examine the microorganisms interacting with the swine host. MethodologyWe used shotgun metagenomic sequencing to analyse the caecal microbiomes of swine from five commercial farms in northern Thailand. ResultsSwine caecal microbiomes contained commensal bacteria such as Bifidobacterium, Lactobacillus, and Faecalibacterium, which are associated with healthy physiology and feed utilisation. We also identified multiple pathogenic and opportunistic bacteria present in all samples, including Escherichia coli, Clostridium botulinum, Staphylococcus aureus, and the Corynebacterium genus. From a One Health perspective, these species are important foodborne and opportunistic pathogens in both humans and agricultural animals. Antimicrobial resistance genes were also detected in all samples, specifically conferring resistance to tetracycline and aminoglycosides which have historically been used extensively in swine farming. ConclusionThe findings further support the need for improved sanitation standards in swine farms, and additional monitoring of agricultural animals and farm workers to reduce contamination and improved produce safety for human consumption.

microbiology↗

Colistin resistance and resistance determinants are mobile among Salmonella enterica isolates from diseased and healthy pigs in Thailand

Salmonella is an important enteric pathogen that poses a threat to human and livestock animal health, with emerging multidrug resistance (MDR) a major public health issue globally. We investigated the prevalence of Salmonella in healthy and diseased pigs from Thai pig farms and determined their phenotypic and genotypic antimicrobial resistance profiles. A total of 150 fecal samples were collected from pigs housed in pens from four separate pig farms in southern Thailand and tested for the presence of Salmonella. Confirmed Salmonella isolates were tested for their susceptibility to 11 antimicrobials, and PCR used to detect known antimicrobial resistance genes (ARGs). Salmonella isolates were cultured from 69% (103/150) of all fecal samples, with higher prevalence in disease pigs (12/15; 80%), compared with healthy pigs (91/135; 67%). Serotype Rissen was the most frequently identified serotype among the Salmonella isolates. Resistance to ampicillin (AMP) (97%), sulfonamide-trimethoprim (SXT) (97%), and tetracycline (TET) (94%) were the most common phenotypes observed. The most common ARGs identified were blaTEM gene (99.%), tetA (87%), sul1 (77%), and dfrA1 (74%), and more than 95% of the Salmonella isolates tested were MDR - based on resistance to three or more antimicrobial classes. The most common antimicrobial resistance pattern exhibited was AMP-TET-SXT (76%), and resistance to colistin (via the mcr-1 gene) was observed in both healthy and diseased pigs. The clonal groups of PFGE analysis in serotype Typhimurium revealed the genetic relationship among Salmonella isolated from healthy and diseased pigs from different pig farms.

microbiology↗

Assessing the pathogenic potential of less common Salmonella enterica serotypes circulating in the Thai pork production chain

Salmonella is a frequent zoonotic foodborne pathogen, with swine and pork meats the most common source of human infection. In Chiang Mai and Lamphun Province in northern Thailand, there has been a high prevalence of salmonellosis for over a decade. Infection is usually with several dominant S. enterica serotypes, including serotypes Rissen and Monophasic Typhimurium. However, several less common serotypes also contribute to disease. Whole genome sequencing of 43 of these less common S. enterica serotypes isolated from the pork production chain through 2011-2014 were used to evaluate their genetic diversity and virulence potential. Salmonella contamination at local retail markets represented cross-contamination from multiple sources, including decontaminated foodstuff. Previous studies have highlighted the importance of host cell adhesion, invasion and intracellular survival for the development of clinical salmonellosis. We screened our dataset for known virulence genes and antimicrobial resistance genes, identifying at least 10 antimicrobial resistance genes in all isolates. These results indicate that these less common S. enterica serotypes also pose a significant public health risk. Our findings support the need for appropriate surveillance of food products going to market to reduce public exposure to highly pathogenic, multi-drug resistant Salmonella. Surveillance throughout the pork production chain would motivate stakeholders to reinforce sanitation standards and help reduce the risk of salmonellosis in humans.

microbiology↗

Non-serotype 2 isolates from healthy pigs are a potential zoonotic reservoir of Streptococcus suis genetic diversity and antimicrobial resistance

Streptococcus suis is a leading cause of bacterial meningitis in SE Asia, with frequent zoonotic transfer to humans associated with close contact with pigs. A small number of invasive lineages are responsible for endemic infection in the swine industry causing considerable global economic losses. A lack of surveillance and a rising trend in clinical treatment failure has raised concerns of growing antimicrobial resistance (AMR) among invasive S. suis. The source-sink dynamics between healthy and disease isolates is poorly understood and, in this study, we sample and sequence a collection of isolates predominantly from healthy pigs in Chiang Mai province, Northern Thailand. Pangenome comparisons with a selection of invasive serotype 2 isolates identified increased genetic diversity and more frequent AMR carriage in isolates from healthy pigs. Multiple antimicrobial resistance genes were identified conferring resistance to aminoglycosides, lincosamides, tetracycline and macrolides. All isolates were non-susceptinle to three or more different antimicrobial classes, and 75% of non-serotype 2 isolates were non-susceptible to 6 or more classes (compared to 37.5% of serotype 2 isolates). Antimicrobial resistance genes were found on integrative and conjugative elements (ICE) previously observed in other species, suggesting mobile gene pool which can be accessed by invasive disease isolates. Significance statementThe zoonotic pathogen Streptococcus suis causes respiratory disease in pigs and is among the most common causative agents of human clinical bacterial meningitis in SE Asia. We collected isolates from farmed healthy pigs in Northern Thailand, representing a source population from which invasive isolates have recently emerged - linked to the pork production industry. Pangenome characterisation of the isolates revealed a reservoir of genetic diversity and antimicrobial resistance suggesting that One Health approaches may be beneficial in tackling the increase in antimicrobial resistance.

microbiology↗

Antimicrobial resistant Salmonella spp. circulating in antibiotic-free organic pig farms of northern-Thailand

We investigated the prevalence of Salmonella circulating in local organic pig farms in northern Thailand and typed isolated clones to better understand the population structure of the underlying Salmonella contamination. In total, 112 samples from 11 organic pig farms were processed from October to December 2018. Salmonella were detected in 9 farms with an overall prevalence of 25.0% (28/112). Prevalence detected in fecal, feeder, and boot swab samples was found to be 32.7% (17/53), 17.7% (6/34), and 20.0% (5/25), respectively. Of the 28 positive strains, Seven Salmonella serotypes were identified, with S. Rissen being the most common (15/28; 53.6%). 89.3% (25/28), 78.6% (22/28) and 71.4% (20/28) of isolated Salmonella were resisted against tetracycline, ampicillin, and sulfamethoxazole-trimethoprim, respectively. From multilocus sequence typing (MLST) analysis, the phylogenetic tree suggests dissemination of specific clones within herds that share routes of pig transportation and point mutations in housekeeping genes within herds. A minimum spanning tree (MST) revealed that Salmonella contamination in organic pig farming is possibly linked with conventional farming. Based on the own results, strictly highly organic practices provide a safe alternative enhancing domestic consumer trust and improve public health safety.

molecular biology↗

Multiple clones of colistin-resistant Salmonella enterica carrying mcr-1 plasmids in meat products and patients in Northern Thailand

Salmonella spp. is an important foodborne pathogen associated with consumption of contaminated food, especially livestock products. Antimicrobial resistance (AMR) in Salmonella has been reported globally and increasing AMR in food production is a major public health issue worldwide. The objective of this study was to describe the genetic relatedness among Salmonella enterica isolates, which displayed identical DNA fingerprint profiles. Ten S. enterica isolates were selected from meat and human cases with an identical rep-PCR profile of serovars Rissen (n=4), Weltevreden (n=4), and Stanley (n=2). We used long-read whole genome sequencing (WGS) on the MinION sequencing platform to type isolates and investigate in silico the presence of specific AMR genes. Antimicrobial susceptibility testing was tested by disk diffusion and gradient diffusion method to corroborate the AMR phenotype. Multidrug resistance and resistance to more than one antimicrobial agent were observed in eight and nine isolates, respectively. Resistance to colistin with an accompanying mcr-1 gene was observed among the Salmonella isolates. The analysis of core genome and whole genome MLST revealed that the Salmonella from meat and human salmonellosis were closely genetic related. Hence, it could be concluded that meat is one of the important sources for Salmonella infection in human. HighlightsO_LIColistin resistance detected in 2 clones from 2 different Salmonella enterica serovars (Rissen and Weltevreden) with accompanying plasmid-borne mcr-1 gene from the food production chain and human clinical salmonellosis. C_LIO_LIHigh prevalence of multidrug resistant isolates and resistance to more than one antimicrobial agent. C_LIO_LIMinION has potential for mobile, rapid and accurate application in veterinary genomic epidemiology studies. C_LI

microbiology↗