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Extended spectrum beta lactamase forming Escherichia coli is considered a threat in severe clinical cases. Food producing animals and poultry in particular are considered a possible reservoir for distribution of resistant bacteria to humans via meat consumption. Data on the concentration of ESBL- E. coli as a prerequisite for estimating consumer exposure is still limited. To evaluate the amount of ESBL- E. coli present in meat of broilers after slaughtering we sampled pooled caecal contents and pooled neck skin samples as meat surrogate of 30 broiler flocks for commensal and ESBL- E. coli at three German slaughterhouses. Although ESBL- E. coli were present in 90% of the flocks caeca, they only made up a fraction of the total E. coli (mean 7.9 log 10 cfu/g), the ratio varying with a median value of 0.07%. Samples of neck skin were positive for ESBL- E. coli in 93.3% of the flocks. However analyses in neck skin pooled samples, revealed countable ESBL- E. coli in only 32.7% (n = 150) of the samples with concentrations between 1.0 and 3.1 log 10 cfu/g. In conclusion, concentrations of ESBL- E. coli seem to be low in this study, thus indicating a limited impact of broiler meat for ESBL- E. coli transmission to humans via consumption. [ABSTRACT FROM AUTHOR]

During 2010, we evaluated the presence of extended-spectrum β-lactamase- and AmpC-producing enterobacteria in broiler chickens at slaughter. Samples (70 carcasses and 51 ceca) from 4 flocks were analyzed by direct plating and after enrichment. Extended-spectrum β-lactamase producers were found in 88.6% and 72.5% of carcasses and ceca, respectively; AmpC producers were found in 52.9% and 56.9% of carcasses and ceca, respectively. Most isolates were identified as Escherichia coli; Enterobacter cloacae (cecum) and Proteus mirabilis (carcass) were found in 2 samples each. Molecular characterization revealed the domination of CTX-M genes; plasmidic AmpC was CIT-like. Phylogenetic grouping of E. coli showed types A (31.5%), B1 (20.2%), B2 (13.5%), and D (34.8%). These findings provide evidence that healthy broilers in Germany are a source for the dissemination of transmissible resistance mechanisms in enterobacteria brought from the rearing environment into the food chain during slaughtering. [ABSTRACT FROM AUTHOR]

ESBL or AmpC β-lactamase producing Enterobacteriaceae is an increasing concern in human medicine. A distribution via the food chain is discussed, but less is known about these bacteria on fresh pork meat. The aim of this study was to investigate the prevalence of ESBL/AmpC Enterobacteriaceae bacteria in fresh pork meat at processing level in Germany. The analysis comprised microbiological hygiene parameters and further pheno- and genotypical characterization of ESBL/AmpC isolates. The examination included three pools of meat and one corresponding meat juice sample from each of the tested pork meat batches (n = 63). ESBL/AmpC producers were found in 42.9% (36.5% confirmed by genotype, gt) of the investigated batches, either in meat or meat juice. Meat juice was more often (28.6%) contaminated with ESBL/AmpC bacteria than meat (20.6%). Hygiene parameters were satisfactory in all samples and were thus not a suitable tool for predicting the presence of ESBL/AmpC producers. Most of the 37 confirmed ESBL/AmpC bacteria were identified as Escherichia coli (n = 18) or Serratia fonticola (n = 13). Susceptibility testing identified 32 of the 37 isolates to be multidrug-resistant. The most common resistance genes TEM, SHV, and CTX-M were found in 19 of the ESBL/AmpC isolates, mostly E . coli . A single detected AmpC β-lactamase producing E . coli carried a CMY-2 gene. Multilocus sequence typing (MLST) investigations of the ESBL/AmpC E . coli revealed 11 different sequence types. In conclusion, fresh pork meat can harbor highly diverse multidrug-resistant ESBL Enterobacteriaceae , even though at low rates. The study suggests that fresh pork meat might be a source for multidrug-resistant ESBL/AmpC Enterobacteriaceae of various origins. Therefore these data contribute to the epidemiological understanding of the distribution of resistant bacteria and the impact of the food chain on public health. [ABSTRACT FROM AUTHOR]

A total of 174 extended-spectrum β-lactamase (ESBL)-producing Escherichia coli isolates collected from humans ( n =140) and healthy broiler chickens ( n = 34) was included in the study. The MIC values of alkyl diaminoethyl glycin hydrochloride, benzethonium chloride, benzalkonium chloride, chlorhexidine, acriflavine, copper sulfate, silver nitrate and zinc chloride were determined by the broth microdilution method. Significant differences in MIC distributions were found between human and avian isolates and between CTX-M-, SHV- and TEM-type ESBL E. coli for chlorhexidine, silver nitrate, zinc chloride and copper sulfate by statistical analysis. Isolates with reduced susceptibility were investigated for the presence and localization of tolerance-mediating genes by PCR analysis and Southern blotting. The genes emrE, mdfA , sugE (c), cueO , copA, zntA and zitB were commonly present in isolates with elevated MICs, while the genes qacE∆1 , qacF , qacH, sugE (p), cusC and pcoA, were less prevalent. In several isolates, a plasmid localization of the genes qacE∆1 , qacF, qacH and sugE (p) on large plasmids >20 kb was detected. [ABSTRACT FROM AUTHOR]