First Known Report of mcr-Harboring Enterobacteriaceae in the Dominican Republic

Abstract

Colistin is a last-resort antibiotic used to treat infections caused by multidrug-resistant Gram-negative bacteria. People with a history of travel to the Dominican Republic have become sick with pathogenic bacteria carrying the mobile colistin resistance gene, mcr-1, during and after traveling. This investigation aimed to identify mcr genes in Enterobacteriaceae isolated from food animal sources in the Dominican Republic. Three hundred and eleven samples were tested, from which 1354 bacterial isolates were obtained. Real-time PCR tests showed that 70.7% (220 out of 311) of the samples and 3.2% (44 out of 1354) of the isolates tested positive for the mcr gene. All RT-PCR presumptive mcr-positive isolates (n = 44) and a subset (n = 133) of RT-PCR presumptive mcr-negative isolates were subjected to whole-genome sequencing. WGS analysis showed that 39 isolates carried the mcr gene, with 37 confirmed as positive through RT-PCR and two as negative. Further, all of the mcr-positive genomes were identified as Escherichia coli and all contained a IncX4 plasmid replicon. Resistant determinants for other antibiotics important for human health were found in almost all isolates carrying mcr genes.

Mobile Colistin Resistance (mcr) Gene-Containing Organisms in Poultry Sector in Low- and Middle-Income Countries: Epidemiology, Characteristics, and One Health Control Strategies

“…The carriage of MGCB by birds could result in the cross-contamination of poultry meat and associated products by these organisms during slaughter, processing, packaging, and selling. Studies have reported the presence of mcr-gene-harbouring organisms in poultry meats obtained from butchers/slaughterhouses/retail markets/supermarkets in China [57,[105][106][107][108][109] (Table S1), India [110], Bangladesh [110], Nepal [69][70][71], Türkiye [111,112], Pakistan [8], Vietnam [84,[113][114][115][116][117][118][119], Indonesia [55], Malaysia [54,120], Iraq [121], Laos [87,122], Tunisia [74], Algeria [123], Egypt [77][78][79], Brazil [124,125], the Dominican Republic [126], and Russia [127]. Worst of all, the storage temperature does not halt the exchange of mcr genes among meat-contaminating organisms since poultry meats stored at 4 • C, 25 • C, and 37 • C were conducive to the rapid exchange of mcr-1 between Salmonella and E. coli [5].…”

“…Among 581 Enterobacterales, 3 (0.51%) MDR ExPEC isolates of ST410 that coexpressed mcr-1 (with ISApl1 upstream of mcr-1) and many other resistance genes conferring resistance to aminoglycosides, fluoroquinolones (qnrB19 and qnrS1), antifolates, β-lactams, and amphenicols on the IncX4 plasmid were detected [76,126]. This suggests that despite the low mcr gene incidence, the poultry sector in the Dominican Republic is a potential source for the dissemination of virulent MGCB into the human and environmental settings, thereby posing a risk to individuals visiting the DR.…”

Effect of Tryptic Digestion on Sensitivity and Specificity in MALDI-TOF-Based Molecular Diagnostics through Machine Learning

“…Each spot was composed of 1 µL of the sample and 1 µL of the CHCA matrix solution described earlier. The S. enterica serovar infantis isolates carrying the bla CTX-M-65 gene were acquired from a previous study conducted in the Dominican Republic, where sample collection and Salmonella isolation adhered to the established project protocols [36][37][38][39]. To confirm the presence or absence of the bla CTX-M-65 gene in the S. infantis isolates, each was first cultured in TSA (MilliporeSigma, Burlington, MA, USA) and incubated at 37 • C for 24 h. Following this, a single colony was selected from the culture plate, inoculated into Tryptic Soy Broth (TSB, MilliporeSigma, Burlington, MA, USA), and incubated overnight in a shaking incubator at 37 • C. Subsequently, DNA extraction was performed using the GenEluteTM bacterial genomic DNA kit (Sigma-Aldrich, NA2100, NA2110, or NA2120, St Louis, MO, USA), following the manufacturer's recommended procedure.…”

Mobile Colistin-Resistant Genes mcr-1, mcr-2, and mcr-3 Identified in Diarrheal Pathogens among Infants, Children, and Adults in Bangladesh: Implications for the Future

“…Earlier studies have shown the genotypic linkage of the mobile colistin resistance gene mcr-1 to phenotypic colistin resistance [ 56 , 57 ]. Since then, variants of mcr -carrying multiple species of Enterobacteriales have been detected in many countries from environments, animals, and humans [ 58 , 59 , 60 , 61 ]. Subsequently, more variants of the transferable colistin resistance mcr gene ( mcr-1 to mcr-9 ) have been described in Enterobacteriaceae [ 62 , 63 ].…”