Antibiotic and antimicrobial resistance

Preliminary unpublished results of the survey of carbapenem- and/or colistin-resistant Enterobacterales (CCRE survey) showed the expansion of carbapenemase-producing Klebsiella pneumoniae (CPKP) sequence type (ST) 39 in 12 of 15 participating Greek hospitals in 2019.

We conducted a rapid survey to determine the extent of spread of CPKP high-risk clones in Greek hospitals in 2022 and compare the distribution of circulating CPKP clones in these hospitals since 2013.

We analysed whole genome sequences and epidemiological data of 310 K. pneumoniae isolates that were carbapenem-resistant or ‘susceptible, increased exposure’ from Greek hospitals that participated in the European survey of carbapenemase-producing Enterobacteriaceae (EuSCAPE, 2013–2014), in the CCRE survey (2019) and in a national follow-up survey (2022) including, for the latter, an estimation of transmission events.

Five K. pneumoniae STs including ST258/512 (n = 101 isolates), ST11 (n = 93), ST39 (n = 56), ST147 (n = 21) and ST323 (n = 13) accounted for more than 90% of CPKP isolates in the dataset. While ST11, ST147 and ST258/512 have been detected in participating hospitals since 2013 and 2014, KPC-2-producing ST39 and ST323 emerged in 2019 and 2022, respectively. Based on the defined genetic relatedness cut-off, 44 within-hospital transmission events were identified in the 2022 survey dataset, with 12 of 15 participating hospitals having at least one within-hospital transmission event.

The recent emergence and rapid spread of new high-risk K. pneumoniae clones in the Greek healthcare system related to within-hospital transmission is of concern and highlights the need for molecular surveillance and enhanced infection prevention and control measures.

Since 2021, an emergence of New Delhi metallo-β-lactamase (NDM)-14-producing Klebsiella pneumoniae has been identified in France. This variant with increased carbapenemase activity was not previously detected in Enterobacterales.

We investigated the rapid dissemination of NDM-14 producers among patients in hospitals in France.

All NDM-14-producing non-duplicate clinical isolates identified in France until June 2022 (n = 37) were analysed by whole genome sequencing. The phylogeny of NDM-14-producers among all K. pneumoniae sequence type (ST) 147 reported in France since 2014 (n = 431) was performed. Antimicrobial susceptibility testing, conjugation experiments, clonal relationship and molecular clock analysis were performed.

The 37 NDM-14 producers recovered in France until 2022 belonged to K. pneumoniae ST147. The dissemination of NDM-14-producing K. pneumoniae was linked to a single clone, likely imported from Morocco and responsible for several outbreaks in France. The gene blaNDM-14 was harboured on a 54 kilobase non-conjugative IncFIB plasmid that shared high homology with a known blaNDM-1-carrying plasmid. Using Bayesian analysis, we estimated that the NDM-14-producing K. pneumoniae ST147 clone appeared in 2020. The evolutionary rate of this clone was estimated to 5.61 single nucleotide polymorphisms per genome per year. The NDM-14 producers were highly resistant to all antimicrobials tested except to colistin, cefiderocol (minimum inhibitory concentration 2 mg/L) and the combination of aztreonam/avibactam.

Highly resistant NDM-14 producing K. pneumoniae can rapidly spread in healthcare settings. Surveillance and thorough investigations of hospital outbreaks are critical to evaluate and limit the dissemination of this clone.

Multidrug-resistant (MDR) bacteria are among chief causes of healthcare-associated infections (HAIs). In Spain, studies addressing multidrug resistance based on epidemiological surveillance systems are lacking.

In this observational study, cases of HAIs by MDR bacteria notified to the epidemiological surveillance system of Andalusia, Spain, between 2014−2021, were investigated. Notified cases and their spatiotemporal distribution were described, with a focus on social determinants of health (SDoH).

New cases during the study period of HAIs caused by extended-spectrum β-lactamase (ESBL)-/carbapenemase-producing Enterobacterales, MDR Acinectobacter baumannii, MDR Pseudomonas aeruginosa or meticillin resistant Staphylococcus aureus were considered. Among others, notification variables included sex and age, while socio-economic variables comprised several SDoH. Cases’ spatial distribution across municipalities was assessed. The smooth standardised incidence ratio (sSIR) was obtained using a Bayesian spatial model. Association between municipalities’ sSIR level and SDoH was evaluated by bivariate analysis.

In total, 6,389 cases with a median age of 68 years were notified; 61.4% were men (n = 3,921). The most frequent MDR bacteria were ESBL-producing Enterobacterales (2,812/6,389; 44.0%); the main agent was Klebsiella spp. (2,956/6,389; 46.3%). Between 2014 and 2021 case numbers appeared to increase. Overall, up to 15-fold differences in sSIR between municipalities were observed. In bivariate analysis, there appeared to be an association between municipalities’ sSIR level and deprivation (p = 0.003).

This study indicates that social factors should be considered when investigating HAIs by MDR bacteria. The case incidence heterogeneity between Andalusian municipalities might be explained by SDoH, but also possibly by under-notification. Automatising reporting may address the latter.

In Denmark, antimicrobial resistance (AMR) in pigs has been monitored since 1995 by phenotypic approaches using the same indicator bacteria. Emerging methodologies, such as metagenomics, may allow novel surveillance ways.

This study aimed to assess the relevance of indicator bacteria (Escherichia coli and Enterococcus faecalis) for AMR surveillance in pigs, and the utility of metagenomics.

We collated existing data on AMR and antimicrobial use (AMU) from the Danish surveillance programme and performed metagenomics sequencing on caecal samples that had been collected/stored through the programme during 1999–2004 and 2015–2018. We compared phenotypic and metagenomics results regarding AMR, and the correlation of both with AMU.

Via the relative abundance of AMR genes, metagenomics allowed to rank these genes as well as the AMRs they contributed to, by their level of occurrence. Across the two study periods, resistance to aminoglycosides, macrolides, tetracycline, and beta-lactams appeared prominent, while resistance to fosfomycin and quinolones appeared low. In 2015–2018 sulfonamide resistance shifted from a low occurrence category to an intermediate one. Resistance to glycopeptides consistently decreased during the entire study period. Outcomes of both phenotypic and metagenomics approaches appeared to positively correlate with AMU. Metagenomics further allowed to identify multiple time-lagged correlations between AMU and AMR, the most evident being that increased macrolide use in sow/piglets or fatteners led to increased macrolide resistance with a lag of 3–6 months.

We validated the long-term usefulness of indicator bacteria and showed that metagenomics is a promising approach for AMR surveillance.

Antimicrobial resistance (AMR) is of public health concern worldwide.

We aimed to summarise the German AMR situation for clinicians and microbiologists.

We conducted a systematic review and meta-analysis of 60 published studies and data from the German Antibiotic-Resistance-Surveillance (ARS). Primary outcomes were AMR proportions in bacterial isolates from infected patients in Germany (2016–2021) and the case fatality rates (2010–2021). Random and fixed (common) effect models were used to calculate pooled proportions and pooled case fatality odds ratios, respectively.

The pooled proportion of meticillin resistance in Staphylococcus aureus infections (MRSA) was 7.9% with a declining trend between 2014 and 2020 (odds ratio (OR) = 0.89; 95% CI: 0.886–0.891; p < 0.0001), while vancomycin resistance in Enterococcus faecium (VRE) bloodstream infections increased (OR = 1.18; (95% CI: 1.16–1.21); p < 0.0001) with a pooled proportion of 34.9%. Case fatality rates for MRSA and VRE were higher than for their susceptible strains (OR = 2.29; 95% CI: 1.91–2.75 and 1.69; 95% CI: 1.22–2.33, respectively). Carbapenem resistance in Gram-negative pathogens (Klebsiella pneumoniae, Acinetobacter baumannii, Enterobacter spp. and Escherichia coli) was low to moderate (< 9%), but resistance against third-generation cephalosporins and fluoroquinolones was moderate to high (5–25%). Pseudomonas aeruginosa exhibited high resistance against carbapenems (17.0%; 95% CI: 11.9–22.8), third-generation cephalosporins (10.1%; 95% CI: 6.6–14.2) and fluoroquinolones (24.9%; 95% CI: 19.3–30.9). Statistical heterogeneity was high (I² > 70%) across studies reporting resistance proportions.

Continuous efforts in AMR surveillance and infection prevention and control as well as antibiotic stewardship are needed to limit the spread of AMR in Germany.

Since the beginning of the war in Ukraine in February 2022, Ukrainians have been seeking shelter in other European countries.

We aimed to investigate the prevalence and the molecular epidemiology of multidrug-resistant Gram-negative (MDRGN) bacteria and meticillin-resistant Staphylococcus aureus (MRSA) in Ukrainian patients at admittance to the University Hospital Frankfurt, Germany.

We performed screening and observational analysis of all patients from March until June 2022. Genomes of MDRGN isolates were analysed for antimicrobial resistance, virulence genes and phylogenetic relatedness.

We included 103 patients (median age: 39 ± 23.7 years), 57 of whom were female (55.3%; 95% confidence interval (CI): 45.2–5.1). Patients were most frequently admitted to the Department of Paediatrics (29/103; 28.2%; 95% CI: 19.7–37.9). We found 34 MDRGN isolates in 17 of 103 patients (16.5%; 95% CI: 9.9–25.1). Ten patients carried 21 carbapenem-resistant (CR) bacteria, five of them more than one CR isolate. Four of six patients with war-related injuries carried eight CR isolates. In six of 10 patients, CR isolates caused infections. Genomic characterisation revealed that the CR isolates harboured at least one carbapenemase gene, blaNDM-1 being the most frequent (n = 10). Core genome and plasmid analysis revealed no epidemiological connection between most of these isolates. Hypervirulence marker genes were found in five of six Klebsiella pneumoniae CR isolates. No MRSA was found.

Hospitals should consider infection control strategies to cover the elevated prevalence of MDRGN bacteria in Ukrainian patients with war-related injuries and/or hospital pre-treatment and to prevent the spread of hypervirulent CR isolates.