Colistin resistance and plasmidmediated mcr genes in Escherichia coli and Salmonella isolated from pigs, pig carcass and pork in Thailand, Lao PDR and Cambodia border provinces

Background@#Colistin and carbapenem-resistant bacteria have emerged and become a serious public health concern, but their epidemiological data is still limited. @*Objectives@#This study examined colistin and carbapenem resistance in Escherichia coli and Salmonella from pigs, pig carcasses, and pork in Thailand, Lao PDR, and Cambodia border provinces. @*Methods@#The phenotypic and genotypic resistance to colistin and meropenem was determined in E. coli and Salmonella obtained from pigs, pig carcasses, and pork (n = 1,619). A conjugative experiment was performed in all isolates carrying the mcr gene (s) (n = 68). The plasmid replicon type was determined in the isolates carrying a conjugative plasmid with mcr by PCR-based replicon typing (n = 7). The genetic relatedness of mcr-positive Salmonella (n = 11) was investigated by multi-locus sequence typing. @*Results@#Colistin resistance was more common in E. coli (8%) than Salmonella (1%). The highest resistance rate was found in E. coli (17.8%) and Salmonella (1.7%) from Cambodia. Colistin-resistance genes, mcr-1, mcr-3, and mcr-5, were identified, of which mcr-1 and mcr-3 were predominant in E. coli (5.8%) and Salmonella (1.7%), respectively. The mcr-5 gene was observed in E. coli from pork in Cambodia. Two colistin-susceptible pig isolates from Thailand carried both mcr-1 and mcr-3. Seven E. coli and Salmonella isolates contained mcr-1 or mcr-3 associated with the IncF and IncI plasmids. The mcr -positive Salmonella from Thailand and Cambodia were categorized into two clusters with 94%–97% similarity. None of these clusters was meropenem resistant. @*Conclusions@#Colistin-resistant E. coli and Salmonella were distributed in pigs, pig carcasses, and pork in the border areas. Undivided-One Health collaboration is needed to address the issue.

Colistin resistance and plasmidmediated mcr genes in Escherichia coli and Salmonella isolated from pigs, pig carcass and pork in Thailand, Lao PDR and Cambodia border provinces

Background@#Colistin and carbapenem-resistant bacteria have emerged and become a serious public health concern, but their epidemiological data is still limited. @*Objectives@#This study examined colistin and carbapenem resistance in Escherichia coli and Salmonella from pigs, pig carcasses, and pork in Thailand, Lao PDR, and Cambodia border provinces. @*Methods@#The phenotypic and genotypic resistance to colistin and meropenem was determined in E. coli and Salmonella obtained from pigs, pig carcasses, and pork (n = 1,619). A conjugative experiment was performed in all isolates carrying the mcr gene (s) (n = 68). The plasmid replicon type was determined in the isolates carrying a conjugative plasmid with mcr by PCR-based replicon typing (n = 7). The genetic relatedness of mcr-positive Salmonella (n = 11) was investigated by multi-locus sequence typing. @*Results@#Colistin resistance was more common in E. coli (8%) than Salmonella (1%). The highest resistance rate was found in E. coli (17.8%) and Salmonella (1.7%) from Cambodia. Colistin-resistance genes, mcr-1, mcr-3, and mcr-5, were identified, of which mcr-1 and mcr-3 were predominant in E. coli (5.8%) and Salmonella (1.7%), respectively. The mcr-5 gene was observed in E. coli from pork in Cambodia. Two colistin-susceptible pig isolates from Thailand carried both mcr-1 and mcr-3. Seven E. coli and Salmonella isolates contained mcr-1 or mcr-3 associated with the IncF and IncI plasmids. The mcr -positive Salmonella from Thailand and Cambodia were categorized into two clusters with 94%–97% similarity. None of these clusters was meropenem resistant. @*Conclusions@#Colistin-resistant E. coli and Salmonella were distributed in pigs, pig carcasses, and pork in the border areas. Undivided-One Health collaboration is needed to address the issue.

Phenotypic and genotypic antimicrobial resistance and virulence genes of Salmonella enterica isolated from pet dogs and cats

Salmonella enterica isolates (n = 122), including 32 serotypes from 113 dogs and 9 cats, were obtained from household dogs (n = 250) and cats (n = 50) during 2012–2015. The isolates were characterized by serotyping, antimicrobial resistance phenotyping and genotyping, and virulence gene screening. Serovars Weltevreden (15.6%) and Typhimurium (13.9%) were the most common. The majority (43%) of the isolates were multidrug resistant. The dog isolates (12.3%) harbored class 1 integrons, of which the dfrA12-aadA2 cassette was most frequent (66.7%). The only class integron in serovar Albany was located on a conjugative plasmid. Two ESBL-producing isolates (i.e., a serovar Krefeld and a serovar Enteritridis) carried bla(TEM) and bla(CTX-M), and the bla(TEM) gene in both was horizontally transferred. Of the plasmid-mediated quinolone resistance genes tested, only qnrS (4.9%) was detected. Most Salmonella isolates harbored invA (100%), prgH (91.8%), and sipB (91%). Positive associations between resistance and virulence genes were observed for bla(PSE-1)/orgA, cmlA/spaN, tolC, and sul1/tolC (p < 0.05). The results suggest that companion dogs and cats are potential sources of S. enterica strains that carry resistance and virulence genes and that antimicrobial use in companion animals may select for the examined Salmonella virulence factors.

In-vitro evaluation of antiseptics and disinfectants against agianst Burkholderia pseudomallei from clinical isolates.

Objective: Chemical widely used as antiseptics and disinfectants for killing various microorganisms in many studies whether no evaluation of chemical agents against B. pseudomallei . Materials: Our study performed  various concentrations of common used as antiseptics and disinfectants in hospitals for example phenol derivatives, alcohol, halogen compounds, aldehyde and quaternary ammonium compounds against B. pseudomallei. These informations will help physician who work in infectious unit easy choose these agents for killing or controlling spread in hospital environment especially  these organisms can survive in water or humid area as Psedomonas aeruginosa. Results: This study using chemical agents in clinic performed in-vitro evaluation on B. pseudomallei from various specimens of Srinagarind hospital by dilution method.  This found that good antiseptics against these organisms were 70%Alcohol 2%ProvidineÒ 0.1%ThimersalÒ and 2% MecurochromeÒ; good disinfectants against that were 4%Formaldehyde, 2%LysolÒ and 3%H2O2. The 0.5% HibitaneÒ  has modertaedly  antibactericidal effect on B. pseudomallei . Both 1:100 SavlonÒ and 0.1%AcriflavinÒ were poor antibactericidal against these organisms. Whereas 1% VirkonÒ  was optimum concentration for killing these organisms and against contaminations not more than 107 cells/ml. Conclusions: The effective chemical agents against  B. pseudomallei  were  0.1-0.5% Chlorine, 4%Foramldehyde, 3%H2O2, 2%LysolÒ, 70%Alcohol, 2%ProvidineÒ, 0.1%ThimerosalÒ and 2% MecurochromeÒKeywords: antiseptics, disinfectants, Burkholderia pseudomallei, clinical isolates