Occurrence of ESBL-Producing Escherichia coli in Livestock and Farm Workers in Mecklenburg-Western Pomerania, Germany

Abstract

In recent years, extended-spectrum β-lactamases (ESBL) producing bacteria have been found in livestock, mainly as asymptomatic colonizers. The zoonotic risk for people working in close contact to animal husbandry has still not been completely assessed. Therefore, we investigated the prevalence of ESBL-producing Escherichia spp. in livestock animals and workers to determine the potential risk for an animal-human cross-transmission.In Mecklenburg-Western Pomerania, northeast Germany, inguinal swabs of 73 individuals with livestock contact from 23 different farms were tested for ESBL-producing Escherichia spp. Two pooled fecal samples per farm of animal origin from 34 different farms (17 pig farms, 11 cattle farms, 6 poultry farms) as well as cloacal swabs of 10 randomly selected broilers or turkeys were taken at each poultry farm. For identification, selective chromogenic agar was used after an enrichment step. Phenotypically ESBL-producing isolates (n = 99) were tested for CTX-M, OXA, SHV and TEM using PCR, and isolates were further characterized using multilocus sequence typing (MLST). In total, 61 diverse isolates from different sources and/or different MLST/PCR results were acquired. Five farm workers (three from cattle farms and two from pig farms) harbored ESBL-producing E. coli. All human isolates harbored the CTX-M β-lactamase; TEM and OXA β-lactamases were additionally detected in two, resp. one, isolates. ESBL-producing Escherichia spp. were found in fecal samples at pig (15/17), cattle (6/11) and poultry farms (3/6). In total, 70.6% (24/36) of the tested farms were ESBL positive. Furthermore, 9 out of 60 cloacal swabs turned out to be ESBL positive. All isolated ESBL-producing bacteria from animal sources were E. coli, except for one E. hermanii isolate. CTX-M was the most prevalent β-lactamase at cattle and pig farms, while SHV predominated in poultry. One human isolate shared an identical MLST sequence type (ST) 3891 and CTX-M allele to the isolate found in the cattle fecal sample from the same farm, indicating a zoonotic transfer. Two other pairs of human-pig and human-cattle E. coli isolates encoded the same ESBL genes but did not share the same MLST ST, which may indicate horizontal resistance gene transfer. In summary, the study shows the high prevalence of ESBL-producing E.coli in livestock in Mecklenburg- Western Pomerania and provides the risk of transfer between livestock and farm workers.

Studies on avian pathogenic Escherichia coli in commercial broiler chicken in South East Queensland

“…The majority of sequence types found among the FQ and ESC resistant isolates in the current study (ST354, ST10, S648 and ST 224) have been previously described globally among humans as well as animals Aizawa et al, 2014;Dahms et al, 2015;Day et al, 2016;Dissanayake et al, 2014;Kim et al, 2011;Maluta et al, 2014;Manges and Johnson, 2012;Sola-Gines et al, 2015;Vignaroli et al, 2012). Nonetheless, four of the FQ resistant FEC isolates belonged to the same sequence type (ST354), but were cultured from different geographical regions indicating that they did not originate from one shed.…”

“…ST2705 and ST6053 are host restricted and have been previously isolated from poultry and wild birds (Dahms et al, 2015;Day et al, 2016;Jones-Dias et al, 2015). The majority of the FQ resistant FEC were identified as ST354 belonging to phylogenetic group F. This ST has been previously identified in pathogenic E. coli from chickens, dogs, cats and pigs as well as in non-pathogenic E. coli, worldwide Mora et al, 2011;Schaufler et al, 2015).…”

“…Wild birds and other animals, such as vermin and rodents, (Dahms et al, 2015) could also disseminate resistant E. coli Laube et al, 2014). Similarly, humans could act as a direct or indirect source of transmission to poultry and the environment (Marathe et al, 2013).…”

“…High prevalence of ESBL-producing E. coli have been detected in livestock in Europe and North America (Dahms et al, 2015;Ewers et al, 2012). In addition, ESBL-producing E. coli have been recently identified in Australian livestock, bovines and porcines .…”

Antimicrobial Resistance in ESBL-Producing Escherichia coli Isolated from Layer and Pig Farms in Thailand

“…This phenomenon has been caused mainly by the growing prevalence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae [5,9,10] and has resulted in increased use of last-resort antimicrobial drugs, e.g. carbapenems and colistin [18].…”