Distribution, Numbers, and Diversity of ESBL-Producing E. coli in the Poultry Farm Environment

Abstract

This study aimed to discern the contribution of poultry farms to the contamination of the environment with ESBL-producing Escherichia coli and therewith, potentially to the spread of these bacteria to humans and other animals. ESBL-producing E. coli were detected at all investigated laying hen farms (n = 5) and broiler farms (n = 3) in 65% (46/71) and 81% (57/70) of poultry faeces samples, respectively. They were detected in rinse water and run-off water (21/26; 81%), other farm animals (11/14; 79%), dust (21/35; 60%), surface water adjacent to farms (20/35; 57%), soil (48/87; 55%), on flies (11/73; 15%), and in barn air (2/33; 6%). The highest prevalence and concentrations in the outdoor environment were observed in soil of free-range areas at laying hen farms (100% of samples positive, geometric mean concentration 2.4×104 cfu/kg), and surface waters adjacent to broiler farms during, or shortly after, cleaning between production rounds (91% of samples positive, geometric mean concentration 1.9×102 cfu/l). The diversity of ESBL-producing E. coli variants with respect to sequence type, phylogenetic group, ESBL-genotype and antibiotic resistance profile was high, especially on broiler farms where on average 16 different variants were detected, and the average Simpson’s Indices of diversity (SID; 1–D) were 0.93 and 0.94 among flock and environmental isolates respectively. At laying hen farms on average nine variants were detected, with SIDs of 0.63 (flock isolates) and 0.77 (environmental isolates). Sixty percent of environmental isolates were identical to flock isolates at the same farm. The highest proportions of ‘flock variants’ were observed in dust (94%), run-off gullies (82%), and barn air (67%), followed by surface water (57%), soil (56%), flies (50%) and other farm animals (35%).The introduction of ESBL-producing E. coli from poultry farms to the environment may pose a health risk if these bacteria reach places where people may become exposed.

Extended-spectrum β-lactamase- and pAmpC-producing Enterobacteriaceae among the general population in a livestock-dense area

“…In contrast to the other types of animals studied, mink are carnivores; they eat raw residual products from the poultry and fish industry at least once a day [27]. Given the fact that ESBL/pAmpC-E have been frequently found in poultry [2,4,6,17], it is likely that mink carry ESBL/pAmpC-E. It is still unclear if, and how, the presence of mink leads to an increased risk for carriage in the community.…”

“…Usually, people working on a farm have a higher carriage rate of ESBL/pAmpC-E than the general population [4,6]. Although several studies hypothesize that exposure to ESBL/ pAmpC-E is elevated in close proximity around animal farms [17,18], the risk of this exposure is not clear [14].…”

Dynamics of CMY-2 producing E. coli in a broiler parent flock

“…In the Netherlands, 56.5% of the broilers at slaughter were carriers of ESBL/pAmpC-Escherichia coli in 2015 (MARAN, 2016). Although prevalence in poultry varies between farms (Blaak et al, 2015), ESBL/pAmpC producing bacteria are present in all levels of the broiler production chain (Dierikx et al, 2013). The broiler production chain has a pyramidal structure, thus the presence of ESBL/pAmpC in the upper levels of the chain might influence the ESBL/ pAmpC status of lower levels in the chain, e.g.…”

Extended-Spectrum-Beta-Lactamase- and Plasmid-Encoded Cephamycinase-Producing Enterobacteria in the Broiler Hatchery as a Potential Mode of Pseudo-Vertical Transmission

“…Especially, those farm animals can act as reservoirs for resistant bacteria and introduce the ESBL-/pAmpC-producing enterobacteria into the food production process (4,(15)(16)(17). Various studies also demonstrated a high prevalence of ESBL/pAmpCproducing enterobacteria in broiler chicken farms and the respective environment in Germany (7,8,(18)(19)(20)(21)(22). It turned out that the 1-day-old (parent) broiler chicks already seemed to be colonized by these resistant bacteria when arriving at the farms (19,23).…”