Diverse Escherichia coli lineages, from domestic animals and humans in a household, carry colistin resistance gene mcr-1 in Ecuador

Loayza Villa, M. F.; Salinas, L.; Villavivencio, F.; Rafael, T.; Salas, S.; Rivera, R.; Villacis, J.; Satan, C.; Ushina, L.; Munoz, O.; Zurita, J.; Melano, R. G.; Tijet, N.; Reyes, J.; Trueba, G.

doi:10.1101/350587

bioRxiv · 10.1101/350587

Diverse Escherichia coli lineages, from domestic animals and humans in a household, carry colistin resistance gene mcr-1 in Ecuador

Loayza Villa, M. F.·Salinas, L.·Villavivencio, F.·Rafael, T.·Salas, S.·Rivera, R.·Villacis, J.·Satan, C.·Ushina, L.·Munoz, O.·Zurita, J.·Melano, R. G.·Tijet, N.·Reyes, J.·Trueba, G.

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Abstract

The aim of this study was to investigate the presence of Escherichia coli carrying mcr-1 gene in domestic animals close to a child who suffered a peritoneal infection by a mcr-1 positive E. coli. Rectal or cloacal swabs and fecal samples from domestic animals were plated on selective media to isolate colistin-resistant E. coli and isolates were submitted to detection of mcr-1 gene, pulsed field gel electrophoresis (PFGE), multi-locus sequence typing (MLST), replicon typing and S1-PFGE. Four mcr-1 positive E. coli isolates (from chicken, turkey and dog) were recovered. No shared PFGE pattern or MLST sequence type were observed among isolates. A 60Kb IncI1{gamma} mcr-1-carrying plasmid was detected in all isolates. Our results suggest that mcr-1 gene was horizontally disseminated amongst different lineages of E. coli from domestic animals in the childs household.\n\nImportanceHorizontally transferable colistin resistance (mcr-1 gene) is thought to have originated in domestic animals and transferred to humans through meat and dairy products. In the present report we show evidence that the mcr-1 gene could be transferred to different E. coli strains colonizing different hosts (humans and pets) in the same household.

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Loayza Villa, M. F., Salinas, L., Villavivencio, F., Rafael, T., Salas, S., Rivera, R., Villacis, J., Satan, C., Ushina, L., Munoz, O., Zurita, J., Melano, R. G., Tijet, N., Reyes, J., Trueba, G.. 2018-06-20. Diverse Escherichia coli lineages, from domestic animals and humans in a household, carry colistin resistance gene mcr-1 in Ecuador. https://doi.org/10.1101/350587

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