Human carriage of ESBL/pAmpC-producing Escherichia coli and Klebsiella pneumoniae in relation to the consumption of raw or undercooked vegetables, fruits, and fresh herbs.

We investigated to what extent the consumption of raw or undercooked vegetables, fruits, and fresh herbs influences carriage rates of ESBL/pAmpC-producing Escherichia coli and Klebsiella pneumoniae (ESBL-E/K) in the general population. We assessed long-term carriage and changes in ESBL-E/K prevalence over time, by comparing the results to findings in the same population 5 years earlier. Between July and December 2021, participants sent in two fecal samples and questionnaires, 3 months apart. Food frequency questionnaires were sent on a monthly basis. Fecal samples were cultured and screened for ESBL-E/K, and phenotypically positive isolates were sequenced. Multivariable logistic regression models were established to assess the association between the consumption of fresh produce and ESBL-E/K carriage. The ESBL-E/K prevalence was 7.6% [41/537; 95% confidence interval (CI): 5.7-10.2] in the first sampling round and 7.0% (34/489; 95% CI: 5.0-9.6) in the second. Multivariable models did not result in statistical significance for any of the selected fruit and vegetable types. Trends for increased carriage rates were observed for the consumption of raspberry and blueberry in the summer period. ESBL-E/K prevalence was comparable with the prevalence in the same cohort 5 years earlier (7.5%; 95% CI: 5.6-10.1%). In six persons (1.2%) a genetically highly homologous ESBL-E/K was found. In conclusion, the contribution of the consumption of raw fruits, vegetables, and herbs to ESBL-E/K carriage in humans in the Netherlands is probably low. Despite COVID-19 containment measures (e.g., travel restrictions, social distancing, and hygiene) the ESBL-E/K prevalence was similar to 5 years earlier. Furthermore, indications for long-term carriage were found.IMPORTANCEESBL-producing bacteria are resistant against important classes of antibiotics, including penicillins and cephalosporines, which complicates treatment of infections. Food is one of the main routes of transmission for carriage of these bacteria in the general population. Although fruits, vegetables, and herbs are generally less frequently contaminated with ESBL-producing bacteria compared to meat, exposure might be higher since these products are often eaten raw or undercooked. This research showed that the contribution of the consumption of raw or undercooked fresh produce to ESBL-E/K carriage in the general Dutch population was low. No specific types of fruit or vegetables could be identified that gave a higher risk of carriage. In addition, we demonstrated the presence of genetically highly homologous ESBL-E/K in six persons after a period of 5 years, indicative for long-term carriage.

Colistin-resistant Enterobacterales among veterinary healthcare workers and in the Dutch population.

Objectives: Plasmid-mediated colistin resistance can be transferred from animals to humans. We investigated the prevalence of carriage of mcr-mediated colistin-resistant Escherichia coli and Klebsiella pneumoniae (ColR-E/K) in veterinary healthcare workers and in the general population in the Netherlands. Methods: Two cross-sectional population studies were performed: one among veterinary healthcare workers and one in the general population. Participants sent in a faecal sample and filled in a questionnaire. Samples were analysed using selective enrichment and culture. Mobile colistin resistance genes (mcr) were detected by PCR and ColR-E/K were sequenced using Illumina and Nanopore technologies. Results: The prevalence of mcr-mediated ColR-E/K was 0.2% (1/482, 95% CI 0.04%-1.17%) among veterinary personnel and 0.8% (5/660, 95% CI 0.3%-1.8%) in the population sample. mcr-1 was found in E. coli from four persons, mcr-8 in K. pneumoniae from one person and another person carried both mcr-1 and mcr-8 in a K. pneumoniae isolate. mcr-1 was found on different plasmid types (IncX4, IncI1 and IncI2), while mcr-8 was found on IncF plasmids only. Conclusions: mcr-mediated ColR-E/K resistance was uncommon in both populations. Professional contact with animals does not increase the chance of carriage of these bacteria in the Netherlands at present. mcr-8 was found for the first time in the Netherlands. Surveillance of colistin resistance and its underlying mechanisms in humans, livestock and food is important in order to identify emerging trends in time.

Seasonality in carriage of extended-spectrum ß-lactamase-producing Escherichia coli and Klebsiella pneumoniae in the general population: a pooled analysis of nationwide cross-sectional studies.

Infections due to extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-E) are often preceded by asymptomatic carriage. Higher incidences in enteric infectious diseases during summer have been reported. Here, we assessed whether the presence of seasonality in intestinal ESBL-Escherichia coli/Klebsiella pneumoniae (ESBL-E/K) carriage in the general Dutch population exists. From 2014 to 2017, the faecal carriage of ESBL-E/K in healthy individuals was determined in three cross-sectional studies in the Netherlands, including 5985 subjects. Results were pooled to identify seasonal trends in prevalence (by month of sampling). Multivariate logistic regression analysis was used to calculate pooled odds ratios and 95% confidence intervals. Results were adjusted for age, sex, antibiotic use and travel. Overall prevalence of ESBL-E/K carriage was 4.3% (n = 260 ESBL-E/K-positive), with differences between months ranging from 2.6% to 7.4%. Compared to January, the monthly prevalence of ESBL-E carriage was highest in August (OR 1.88, 95% CI 1.02-3.49) and September (OR 2.25, 95% CI 1.30-3.89). The observed monthly differences in ESBL-E/K carriage rates suggest that there is seasonal variation in exposure to ESBL-E/K other than due to travelling and antibiotic use. This should be taken into account in designing future ESBL-E prevalence studies in temperate regions.

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

OBJECTIVES: In the Netherlands there is an ongoing debate regarding environmental health risks of livestock farming for neighbouring residents. This explorative study aims to determine the prevalence of carriage of extended-spectrum ß-lactamase and/or plasmid-mediated AmpC-producing Enterobacteriaceae (ESBL/pAmpC-E) in the general population living in a livestock-dense area, and to study associations between determinants, including exposure through contact with animals and the environment, and human carriage of ESBL/pAmpC-E. METHODS: A cross-sectional study was performed among 2432 adults (aged 20-72 years) in 12 temporary research centres in the south of the Netherlands, consisting of a questionnaire and analysis of a faecal sample to assess carriage of ESBL/pAmpC-E. Risk factors were analysed using logistic regression. RESULTS: The prevalence for carriage of ESBL/pAmpC-E was 4.5% (109/2432; 95% CI 3.7-5.4) ranging from 1.4% to 10.9% among the research centres. ESBL/pAmpC resistance genes were detected in Escherichia coli and Klebsiella pneumoniae isolates obtained from these 109 persons and the most common ESBL-resistance genes were blaCTX-M-15, blaCTX-M-14/17 and blaCTX-M-1, originating from 76 participants. Travel in the previous 12 months to Africa, Asia or Latin America (OR 2.82; 95% CI 1.71-4.63), having kept cows for a hobby in the previous 5 years (OR 3.77; 95% CI 1.22-11.64), usage of proton-pump inhibitors (OR 1.84; 95% CI 1.05-3.23), and living within 1000 m of a mink farm (OR 2.26; 95% CI 1.28-3.98) were identified as risk factors. Exposure to poultry was not identified as a risk factor. CONCLUSIONS: Overall, living in close proximity to livestock animals and farms does not seem to be a risk factor for carriage of ESBL/pAmpC-E.

Occurrence and characteristics of extended-spectrum-ß-lactamase- and AmpC-producing clinical isolates derived from companion animals and horses.

OBJECTIVES: To investigate the occurrence and characteristics of extended-spectrum ß-lactamase (ESBL)- and AmpC-producing Enterobacteriaceae isolates in clinical samples of companion animals and horses and compare the results with ESBL/AmpC-producing isolates described in humans. METHODS: Between October 2007 and August 2009, 2700 Enterobacteriaceae derived from clinical infections in companion animals and horses were collected. Isolates displaying inhibition zones of ≤ 25 mm for ceftiofur and/or cefquinome by disc diffusion were included. ESBL/AmpC production was confirmed by combination disc tests. The presence of resistance genes was identified by microarray, PCR and sequencing, Escherichia coli genotypes by multilocus sequence typing and antimicrobial susceptibility by broth microdilution. RESULTS: Sixty-five isolates from dogs (n = 38), cats (n = 14), horses (n = 12) and a turtle were included. Six Enterobacteriaceae species were observed, mostly derived from urinary tract infections (n = 32). All except 10 isolates tested resistant to cefotaxime and ceftazidime by broth microdilution using clinical breakpoints. ESBL/AmpC genes observed were bla(CTX-M-1, -2, -9, -14, -15,) bla(TEM-52), bla(CMY-2) and bla(CMY-)(39). bla(CTX-M-1) was predominant (n = 17). bla(CTX-M-9) occurred in combination with qnrA1 in 3 of the 11 Enterobacter cloacae isolates. Twenty-eight different E. coli sequence types (STs) were found. E. coli carrying bla(CTX-M-1) belonged to 13 STs of which 3 were previously described in Dutch poultry and patients. CONCLUSIONS: This is the first study among a large collection of Dutch companion animals and horses characterizing ESBL/AmpC-producing isolates. A similarity in resistance genes and E. coli STs among these isolates and isolates from Dutch poultry and humans may suggest exchange of resistance between different reservoirs.

Bovine antibody-based oral immunotherapy for reduction of intragastric Helicobacter pylori colonization: a randomized clinical trial.

BACKGROUND: Antibiotic-based regimens are frequently used for the treatment of Helicobacter pylori infection. These regimens fail to eradicate H pylori in 15% to 40% of patients, primarily due to antimicrobial resistance and insufficient patient compliance. Effective prevention and eradication of H pylori by passive immunization with orally administered bovine antibodies has been demonstrated in animal studies, and may serve as an alternative therapy in humans. OBJECTIVE: To study the efficacy and safety of orally administered bovine anti-H pylori antibodies for the reduction of intragastric bacterial load and eradication of H pylori in humans. METHODS: Dairy cows were immunized against H pylori. After confirmation of the presence of anti-H pylori antibodies in the milk, the milk was subsequently processed into a whey protein concentrate (WPC). In a prospective, double-blind, placebo-controlled randomized clinical trial, H pylori-infected subjects were randomly assigned to treatment with the WPC preparation or placebo. Study medication was continued for 28 days; subjects were followed-up for 56 days. RESULTS: Of the 30 subjects included, 27 completed the protocol. Of these 27 evaluable subjects, 14 were treated with WPC and 13 with placebo. There was no significant difference in urea breath test decrease between the WPC- and placebo-treated group (P=0.75). H pylori-associated gastritis and density were not significantly reduced in either group after treatment (P>0.05 for all). CONCLUSION: Bovine antibody-based oral immunotherapy appears to be safe, but does not significantly reduce intragastric density in humans. Further studies are needed to determine whether WPC treatment has additional value to conventional antibiotic treatment for H pylori.

Dutch patients, retail chicken meat and poultry share the same ESBL genes, plasmids and strains.

Intestinal carriage of extended-spectrum beta-lactamase (ESBL) -producing bacteria in food-producing animals and contamination of retail meat may contribute to increased incidences of infections with ESBL-producing bacteria in humans. Therefore, distribution of ESBL genes, plasmids and strain genotypes in Escherichia coli obtained from poultry and retail chicken meat in the Netherlands was determined and defined as 'poultry-associated' (PA). Subsequently, the proportion of E. coli isolates with PA ESBL genes, plasmids and strains was quantified in a representative sample of clinical isolates. The E. coli were derived from 98 retail chicken meat samples, a prevalence survey among poultry, and 516 human clinical samples from 31 laboratories collected during a 3-month period in 2009. Isolates were analysed using an ESBL-specific microarray, sequencing of ESBL genes, PCR-based replicon typing of plasmids, plasmid multi-locus sequence typing (pMLST) and strain genotyping (MLST). Six ESBL genes were defined as PA (bla(CTX-M-1) , bla(CTX-M-2) , bla(SHV-2) , bla(SHV-12) , bla(TEM-20) , bla(TEM-52) ): 35% of the human isolates contained PA ESBL genes and 19% contained PA ESBL genes located on IncI1 plasmids that were genetically indistinguishable from those obtained from poultry (meat). Of these ESBL genes, 86% were bla(CTX-M-1) and bla(TEM-52) genes, which were also the predominant genes in poultry (78%) and retail chicken meat (75%). Of the retail meat samples, 94% contained ESBL-producing isolates of which 39% belonged to E. coli genotypes also present in human samples. These findings are suggestive for transmission of ESBL genes, plasmids and E. coli isolates from poultry to humans, most likely through the food chain.

[Multiresistant Brachyspira hyodysenteriae in a Dutch sow herd]. / Multiresistentie bij Brachyspira hyodysenteriae-isolaten op een varkensvermeerderingsbedrijf in Nederland.

This case study describes the isolation ofa multiresistant strain ofBrachyspira hyodysenteriae in April 2007 in a Dutch sow herd with recurrent diarrhoea. Examination of faecal samples taken from 7-month-old breeding gilts with diarrhoea revealed the presence of resistance against tiamulin, lincomycin, tylosin, doxycycline, and tylvalosin (the active substance in Aivlosin) in four of five samples. Tiamulin resistance has not been reported in The Netherlands before. The repeated use of tiamulin on the affected farm was assumed to be the main cause of the development of resistance to the drug. The farmer was advised to adopt a medication strategy and to implement management practices that would prevent an ongoing cycle of infection on the farm. It is important that the Dutch swine industry appreciates that tiamulin-resistant strains of B. hyodysenteriae may be found on other farms as well. The appropriate and prudent use of antibiotics is essential in order to prevent the development of resistance against the last option left to cure B. hyodysenteriae infections: valnemulin.