On the island of Zanzibar people in the community are frequently colonized with the same MDR Enterobacterales found in poultry and retailed chicken meat

Abstract

Abstract Objectives Intestinal colonization with extended-spectrum cephalosporin-resistant (ESC-R) and colistin-resistant (CST-R) Enterobacterales (Ent) can be driven by contact with colonized animals and/or contamination of the food chain. We studied the ESC-R-Ent and COL-R-Ent colonizing poultry as well as contaminating chicken meat in Zanzibar (Tanzania). Results were compared with recently published data obtained from rectal swabs of people in the community. Methods During June and July 2018, we collected poultry faecal material (n = 62) and retail chicken meat (n = 37) samples. ESC-R and CST-R strains were isolated implementing selective approaches and characterized with different molecular methods, including WGS coupled with core-genome analyses. Results The prevalence of ESC-R-Ent and CST-R-Ent, respectively, were: 88.7% and 48.4% in poultry; and 43.2% and 18.9% in chicken meat. Overall, the following strains and main resistance mechanisms were found in the two settings: 69 ESC-R Escherichia coli (CTX-M-15 subgroup, 75%), 34 ESC-R Klebsiella pneumoniae (CTX-M-9 group, 54.5%), 24 non-ESC-R but CST-R E. coli (mcr-1, 95.8%) and 17 non-ESC-R but CST-R K. pneumoniae (D150G substitution in PhoQ). Several clones (differing by only 0–13 single nucleotide variants) were concomitantly and frequently found in human and non-human settings: mcr-1-carrying E. coli ST46; CTX-M-15-producing E. coli ST361; CTX-M-14-producing K. pneumoniae ST17; and CTX-M-15-producing K. pneumoniae ST1741. Conclusions This is one of the few studies that have assessed the occurrence of identical MDR Enterobacterales in human and non-human settings. The frequent human gut colonization observed in the community might be favoured by the spread of ESC-R-Ent and CST-R-Ent in poultry and chicken meat. Further studies with a One Health approach should be carried out to better investigate this phenomenon.