Association of intestinal colonization of ESBL-producing Enterobacteriaceae in poultry slaughterhouse workers with occupational exposure-A German pilot study.

BACKGROUND:Bacteria that have acquired antimicrobial resistance, in particular ESBL-producing Enterobacteriaceae, are an important healthcare concern. Therefore, transmission routes and risk factors are of interest, especially for the carriage of ESBL-producing E. coli. Since there is an enhanced risk for pig slaughterhouse employees to carry ESBL-producing Enterobacteriaceae, associated with animal contact as potential risk factor, the present study investigated the occurrence of ESBL-producing Enterobacteriaceae in poultry slaughterhouse employees. Due to the higher level of resistant Enterobacteriaceae in primary poultry production than in pig production, a higher risk of intestinal colonization of poultry slaughterhouse employees was expected. RESULTS:ESBL-producing Enterobacteriaceae were detected in 5.1% (5 of 99) of the fecal samples of slaughterhouse workers. The species of these isolates was confirmed as E. coli. PCR assays revealed the presence of the genes blaCTX-M-15 (n = 2) and blaSHV-12 (n = 3) in these isolates, partly in combination with the β-lactamase gene blaTEM-135. Participants were divided into two groups according to their occupational exposure and results indicated an increased probability of colonization with ESBL-producing Enterobacteriaceae for the group of 'higher exposure' (OR 3.7, exact 95% CI 0.6-23.5; p = 0.4). For intestinal colonization with ESBL-producing Enterobacteriaceae, a prevalence of 10% (3/30) was observed in the group of 'higher exposure' versus 2.9% (2/69) in the group of 'lower exposure'. Employees in working steps such as 'hanging' poultry in the process of slaughter and 'evisceration' seemed to have a higher risk for intestinal colonization with ESBL-producing Enterobacteriaceae compared to the group of 'lower exposure'. CONCLUSION:This study is the first of its kind to collect data on the occupational exposure of slaughterhouse workers to ESBL-producing Enterobacteriaceae in Europe. The results suggested that colonization with ESBL-producing Enterobacteriaceae is associated with occupational exposure in poultry slaughterhouses. However, the presence of ESBL-producing E. coli isolates in only 5.1% (5/99) of the tested employees in poultry slaughterhouses suggests a lower transmission risk than in pig slaughterhouses

Titanium hydroamination catalysts bearing a 2-aminopyrrolinato spectator ligand: monitoring the individual reaction steps

A series of new titanium half sandwich complexes, containing a 2-aminopyrrolinato ligand {NXylN}− as the ancillary ligand, have been prepared and are shown to be pre-catalysts for the hydroamination of alkynes. The coordination of {NXylN}− to titanium was achieved by reaction of [Cp*TiMe3] with the protioligand NXylNH giving [Cp*Ti(NXylN)(Me)2] (1). Upon reaction of complex 1 with an excess of tert-butylamine, the imido complex [Cp*Ti(NXylN)(NtBu)(NH2tBu)] (2) was formed. The latter provided the preparative entry to the synthesis of a range of N-aryl substituted imido complexes. Imido ligand exchange with 2,6-dimethylaniline, 2,4,6-trimethylaniline as well as 2,6-diisopropylaniline gave the corresponding arylimido complexes 3–5 in clean reactions. Reaction of the titanium imido complex [Cp*Ti(NXylN)(NtBu)(NH2tBu)] 2 with terminal arylacetylenes, such as phenylacetylene and tolylacetylene, led to C–H activation and the formation of alkynyl/amido complexes, whereas the arylimido complexes 3 and 5 cleanly underwent {2 + 2} cycloaddition, giving the azatitanacyclobutene derivatives. A single-crystal X-ray structure analysis of the azatitanacyclobutene [Cp*Ti(NXylN){κ2N(2,6-C6H3Me2)CTolCH}] (11) provided the first crystallographically characterized Markovnikov cycloaddition product of an imidotitanium complex with a terminal alkyne. The mechanistic aspects of the hydromanination of alkynes with the new Ti half sandwich complexes were studied and established a reversible {2 + 2} cycloaddition step and the cleavage of the metallacyclic intermediate as the rate determining step in the catalytic cycle. The titanium half sandwich imido complexes were found to be active catalysts for the inter- and intramolecular hydroamination of a broad range of alkynes and ω-aminoalkynes

Synthesis and Coordination Chemistry of Hexadentate Picolinic Acid Based Bispidine Ligands

The synthesis and Cu^II, Ni^II, Zn^II, Co^II, and Ga^III coordination chemistry of the two isomeric hexadentate N₅O ligands 6-[[9-hydroxy-1,5-bis­(methoxycarbonyl)-7-methyl-6,8-bis­(pyridin-2-yl)-3,7-diazabicyclo[3.3.1]­nonan-3-yl]­methyl]­picolinic acid (Hbispa^1a) and 6-[[9-hydroxy-1,5-bis­(methoxycarbonyl)-7-methyl-2,4-bis­(pyridin-2-yl)-3,7-diazabicyclo[3.3.1]­nonan-3-yl]­methyl]­picolinic acid (Hbispa^1b), picolinic acid-appended bispidines, are described. The two ligands are highly preorganized for octahedral coordination geometries and are particularly well suited for tetragonal symmetries, i.e., for Jahn–Teller labile ground states. This is confirmed by all data presented: solid-state structures, solution spectroscopy, electrochemistry, and Cu^II complex stabilities. Differences in the preorganization of the two isomers for the Jahn–Teller labile Cu^II centers are thoroughly analyzed on the basis of the crystal structures and an angular-overlap-model-based ligand-field analysis

Synthesis and Coordination Chemistry of Hexadentate Picolinic Acid Based Bispidine Ligands

The synthesis and Cu^II, Ni^II, Zn^II, Co^II, and Ga^III coordination chemistry of the two isomeric hexadentate N₅O ligands 6-[[9-hydroxy-1,5-bis­(methoxycarbonyl)-7-methyl-6,8-bis­(pyridin-2-yl)-3,7-diazabicyclo[3.3.1]­nonan-3-yl]­methyl]­picolinic acid (Hbispa^1a) and 6-[[9-hydroxy-1,5-bis­(methoxycarbonyl)-7-methyl-2,4-bis­(pyridin-2-yl)-3,7-diazabicyclo[3.3.1]­nonan-3-yl]­methyl]­picolinic acid (Hbispa^1b), picolinic acid-appended bispidines, are described. The two ligands are highly preorganized for octahedral coordination geometries and are particularly well suited for tetragonal symmetries, i.e., for Jahn–Teller labile ground states. This is confirmed by all data presented: solid-state structures, solution spectroscopy, electrochemistry, and Cu^II complex stabilities. Differences in the preorganization of the two isomers for the Jahn–Teller labile Cu^II centers are thoroughly analyzed on the basis of the crystal structures and an angular-overlap-model-based ligand-field analysis

Assigning Defined Daily/Course Doses for Antimicrobials in Turkeys to Enable a Cross-Country Quantification and Comparison of Antimicrobial Use

Antimicrobial resistance (AMR) threatens our public health and is mainly driven by antimicrobial usage (AMU). For this reason the World Health Organization calls for detailed monitoring of AMU over all animal sectors involved. Therefore, we aimed to quantify AMU on turkey farms. First, turkey-specific Defined Daily Dose (DDDturkey) was determined. These were compared to the broiler alternative from the European Surveillance of Veterinary Antimicrobial Consumption (DDDvet), that mention DDDvet as a proxy for other poultry species. DDDturkey ranged from being 81.5% smaller to 48.5% larger compared to its DDDvet alternative for broilers. Second, antimicrobial treatments were registered on 60 turkey farms divided over France, Germany and Spain between 2014 and 2016 (20 flocks per country). Afterwards, AMU was quantified using treatment incidence (TI) per 100 days. TI expresses the percentage of the rearing period that the turkeys were treated with a standard dose of antimicrobials. Minimum, median and maximum TI at flock level and based on DDDturkey = 0.0, 10.0 and 65.7, respectively. Yet, a huge variation in amounts of antimicrobials used at flock level was observed, both within and between countries. Seven farms (12%) did not use any antimicrobials. Aminopenicillins, polymyxins, and fluoroquinolones were responsible for 72.2% of total AMU. The proportion of treating farms peaked on week five of the production cycle (41.7%), and 79.4% of the total AMU was administered in the first half of production. To conclude, not all DDDvet values for broilers can be applied to turkeys. Additionally, the results of AMU show potential for reducing and improving AMU on turkey farms, especially concerning the usage of critically important antimicrobials

Assigning Defined Daily/Course Doses for Antimicrobials in Turkeys to Enable a Cross-Country Quantification and Comparison of Antimicrobial Use

Antimicrobial resistance (AMR) threatens our public health and is mainly driven by antimicrobial usage (AMU). For this reason the World Health Organization calls for detailed monitoring of AMU over all animal sectors involved. Therefore, we aimed to quantify AMU on turkey farms. First, turkey-specific Defined Daily Dose (DDDturkey) was determined. These were compared to the broiler alternative from the European Surveillance of Veterinary Antimicrobial Consumption (DDDvet), that mention DDDvet as a proxy for other poultry species. DDDturkey ranged from being 81.5% smaller to 48.5% larger compared to its DDDvet alternative for broilers. Second, antimicrobial treatments were registered on 60 turkey farms divided over France, Germany and Spain between 2014 and 2016 (20 flocks per country). Afterwards, AMU was quantified using treatment incidence (TI) per 100 days. TI expresses the percentage of the rearing period that the turkeys were treated with a standard dose of antimicrobials. Minimum, median and maximum TI at flock level and based on DDDturkey = 0.0, 10.0 and 65.7, respectively. Yet, a huge variation in amounts of antimicrobials used at flock level was observed, both within and between countries. Seven farms (12%) did not use any antimicrobials. Aminopenicillins, polymyxins, and fluoroquinolones were responsible for 72.2% of total AMU. The proportion of treating farms peaked on week five of the production cycle (41.7%), and 79.4% of the total AMU was administered in the first half of production. To conclude, not all DDDvet values for broilers can be applied to turkeys. Additionally, the results of AMU show potential for reducing and improving AMU on turkey farms, especially concerning the usage of critically important antimicrobials

Risk factors for the abundance of antimicrobial resistance genes aph(3′)-III, erm (B) , sul2 and tet (W) in pig and broiler faeces in nine European countries

International audienceAbstract Objectives The occurrence and zoonotic potential of antimicrobial resistance (AMR) in pigs and broilers has been studied intensively in past decades. Here, we describe AMR levels of European pig and broiler farms and determine the potential risk factors. Methods We collected faeces from 181 pig farms and 181 broiler farms in nine European countries. Real-time quantitative PCR (qPCR) was used to quantify the relative abundance of four antimicrobial resistance genes (ARGs) [aph(3′)-III, erm(B), sul2 and tet(W)] in these faeces samples. Information on antimicrobial use (AMU) and other farm characteristics was collected through a questionnaire. A mixed model using country and farm as random effects was performed to evaluate the relationship of AMR with AMU and other farm characteristics. The correlation between individual qPCR data and previously published pooled metagenomic data was evaluated. Variance component analysis was conducted to assess the variance contribution of all factors. Results The highest abundance of ARG was for tet(W) in pig faeces and erm(B) in broiler faeces. In addition to the significant positive association between corresponding ARG and AMU levels, we also found on-farm biosecurity measures were associated with relative ARG abundance in both pigs and broilers. Between-country and between-farm variation can partially be explained by AMU. Different ARG targets may have different sample size requirements to represent the overall farm level precisely. Conclusions qPCR is an efficient tool for targeted assessment of AMR in livestock-related samples. The AMR variation between samples was mainly contributed to by between-country, between-farm and within-farm differences, and then by on-farm AMU

Assigning Defined Daily/Course Doses for Antimicrobials in Turkeys to Enable a Cross-Country Quantification and Comparison of Antimicrobial Use

Antimicrobial resistance (AMR) threatens our public health and is mainly driven by antimicrobial usage (AMU). For this reason the World Health Organization calls for detailed monitoring of AMU over all animal sectors involved. Therefore, we aimed to quantify AMU on turkey farms. First, turkey-specific Defined Daily Dose (DDDturkey) was determined. These were compared to the broiler alternative from the European Surveillance of Veterinary Antimicrobial Consumption (DDDvet), that mention DDDvet as a proxy for other poultry species. DDDturkey ranged from being 81.5% smaller to 48.5% larger compared to its DDDvet alternative for broilers. Second, antimicrobial treatments were registered on 60 turkey farms divided over France, Germany and Spain between 2014 and 2016 (20 flocks per country). Afterwards, AMU was quantified using treatment incidence (TI) per 100 days. TI expresses the percentage of the rearing period that the turkeys were treated with a standard dose of antimicrobials. Minimum, median and maximum TI at flock level and based on DDDturkey = 0.0, 10.0 and 65.7, respectively. Yet, a huge variation in amounts of antimicrobials used at flock level was observed, both within and between countries. Seven farms (12%) did not use any antimicrobials. Aminopenicillins, polymyxins, and fluoroquinolones were responsible for 72.2% of total AMU. The proportion of treating farms peaked on week five of the production cycle (41.7%), and 79.4% of the total AMU was administered in the first half of production. To conclude, not all DDDvet values for broilers can be applied to turkeys. Additionally, the results of AMU show potential for reducing and improving AMU on turkey farms, especially concerning the usage of critically important antimicrobials