Travel-acquired ESBL-producing Enterobacteriaceae: impact of colonization at individual and community level

Edible river fish-derived extended-spectrum β-lactamase (ESBL)-producing Enterobacterales harboring transferable plasmids encoding bla CTX-M-15, bla CTX-M-27, and bla CTX-M-55

Transmission of extended-spectrum β-lactamase (ESBL) genes has increased the global prevalence of ESBL-producing bacteria, especially in developing countries. Human infection with these bacteria may be food-mediated but has not been fully elucidated. Therefore, we aimed to examine ESBL-producing bacteria in edible river fish and elucidate their potential for horizontal gene transfer. A total of 173 ESBL-producing Enterobacterales were isolated (Escherichia coli [n = 87], Klebsiella pneumoniae [n = 52], Enterobacter cloacae complex [n = 18], Citrobacter freundii complex [n = 14], Atlantibacter hermannii [n = 1] and Serratia fonticola [n = 1]) from 56 of 80 fish intestinal contents sampled. Among the bacterial bla CTX-M genotypes, bla CTX-M-55 was the most predominant, followed by bla CTX-M-15, bla CTX-M-27, and bla CTX-M-65. Furthermore, we found that ESBL-producing Enterobacterales were able to transfer their bla CTX-M genes to E. coli. In summary, our results suggest that ESBL-producing Enterobacterales transfer bla CTX-M to indigenous gut E. coli in humans, following the consumption of contaminated fish.

Predominance of multidrug-resistant Salmonella Typhi genotype 4.3.1 with low-level ciprofloxacin resistance in Zanzibar

BACKGROUND

Typhoid fever is a common cause of febrile illness in low- and middle-income countries. While multidrug-resistant (MDR) Salmonella Typhi (S. Typhi) has spread globally, fluoroquinolone resistance has mainly affected Asia.

METHODS

Consecutively, 1038 blood cultures were obtained from patients of all age groups with fever and/or suspicion of serious systemic infection admitted at Mnazi Mmoja Hospital, Zanzibar in 2015-2016. S. Typhi were analyzed with antimicrobial susceptibility testing and with short read (61 strains) and long read (9 strains) whole genome sequencing, including three S. Typhi strains isolated in a pilot study 2012-2013.

RESULTS

Sixty-three S. Typhi isolates (98%) were MDR carrying blaTEM-1B, sul1 and sul2, dfrA7 and catA1 genes. Low-level ciprofloxacin resistance was detected in 69% (43/62), with a single gyrase mutation gyrA-D87G in 41 strains, and a single gyrA-S83F mutation in the non-MDR strain. All isolates were susceptible to ceftriaxone and azithromycin. All MDR isolates belonged to genotype 4.3.1 lineage I (4.3.1.1), with the antimicrobial resistance determinants located on a composite transposon integrated into the chromosome. Phylogenetically, the MDR subgroup with ciprofloxacin resistance clusters together with two external isolates.

CONCLUSIONS

We report a high rate of MDR and low-level ciprofloxacin resistant S. Typhi circulating in Zanzibar, belonging to genotype 4.3.1.1, which is widespread in Southeast Asia and African countries and associated with low-level ciprofloxacin resistance. Few therapeutic options are available for treatment of typhoid fever in the study setting. Surveillance of the prevalence, spread and antimicrobial susceptibility of S. Typhi can guide treatment and control efforts.

Antimicrobial Resistance in Qatar: Prevalence and Trends before and Amidst the COVID-19 Pandemic

Antimicrobial resistance (AMR) is a global healthcare challenge with substantial morbidity, mortality, and management costs. During the COVID-19 pandemic, there was a documented increase in antimicrobial consumption, particularly for severe and critical cases, as well as noticeable travel and social restriction measures that might influenced the spectrum of AMR. To evaluate the problem, retrospective data were collected on bacterial infections and antimicrobial susceptibility patterns in Qatar before and after the pandemic from 1 January 2019 to 31 December 2021, covering 53,183 pathogens isolated from reported infection episodes. The findings revealed a significant resistance pattern for extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-EBC), carbapenem-resistant Enterobacteriaceae (CR-EBC), and carbapenem-resistant Pseudomonas aeruginosa (CRPA), ciprofloxacin-resistant Salmonella and methicillin-resistant Staphylococcus aureus (MRSA). For correlation with social restrictions, ESBL-EBC and MRSA were positively correlated with changing patterns of international travel (ρ = 0.71 and 0.67, respectively; p < 0.05), while CRPA was moderately correlated with the number of COVID-19 hospitalized patients (ρ = 0.49; p < 0.05). CREBC and CRPA respiratory infections were associated with hospitalized patients (OR: 3.08 and 2.00, respectively; p < 0.05). The findings emphasize the challenges experienced during the COVID-19 pandemic and links to international travel, which probably will influence the local epidemiology of AMR that needs further surveillance and control strategies.

International travel increases risk of urinary tract infection caused by extended-spectrum beta-lactamase-producing Enterobacterales-three-arm case-control study

BACKGROUND

Extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-PE) have worldwide become increasingly prevalent as pathogens causing urinary tract infections (UTIs), posing challenges in their treatment. Of particular concern are travellers to low- and middle-income countries (LMICs), a substantial proportion of whom become colonized by ESBL-PE, with UTIs as the most common clinical manifestation. Seeking tools for preventing ESBL-PE UTI, we explored factors associated with (i) any UTI (versus control), (ii) ESBL-PE UTI (versus control) and (iii) ESBL-PE versus non-ESBL-PE UTI.

METHODS

During 2015-20, we recruited patients with recent ESBL-PE or non-ESBL-PE UTIs, and controls with no UTI to fill in questionnaires covering potential (ESBL-PE-)UTI risk factors.

RESULTS

Of our 430 participants, 130 had ESBL-PE UTI and 187 non-ESBL-PE UTI; 113 were controls. Our three comparisons showed several risk factors as exemplified for any UTI versus controls by female sex, lower education, age, diabetes, antibiotic use, diarrhoea; for ESBL-PE UTI versus controls by travel to LMICs, antibiotic use, swimming; and ESBL-PE versus non-ESBL-PE UTI by male sex, higher education, LMIC travel (participant/household member), pets and antibiotic use. Weekly fish meals appeared protective against both UTI and ESBL-PE UTI.

CONCLUSIONS

Of the numerous factors predisposing to UTI and/or ESBL-PE UTI, our study highlights antibiotic use and LMIC travel. Household members' LMIC travel appears to pose a risk of ESBL-PE UTI, pointing to household transmission of travel-acquired uropathogens. As predisposing factors to multidrug-resistant UTI, international travel and antibiotic use constitute practical targets for prevention efforts.

[Antibiotic resistance: a good example of the "one health" concept]

Antibiotic resistance is the direct deleterious consequence of two synergistic causes linked to human activity: the massive use of antibiotics in human and animal health, which leads to the selection of the most resistant bacteria, and the spread of these selected resistant bacteria, directly by cross-transmission within human and animal populations and indirectly via the environment. The "one health" concept enables an integrated approach of the various components of the issue, linking human, animal and environmental ecosystems and their dynamics.

Dissecting bloodstream infections in febrile neutropenic patients with hematological malignancies, a decade-long single center retrospective observational study (2009-2019)

BACKGROUND

The use of ill-suited antibiotics is a significant risk factor behind the increase in the mortality, morbidity, and economic burden for patients who are under treatment for hematological malignancy (HM) and bloodstream infections (BSI). Such unfitting treatment choices intensify the evolution of resistant variants which is a public health concern due to possible healthcare-associated infection spread to the general population. Hence, this study aims to evaluate antibiograms of patients with BSI and risk factors associated with septicemia.

METHODS

A total of 1166 febrile neutropenia episodes (FNE) among 513 patients with HM from the National Center for Cancer Care and Research (NCCCR), Qatar, during 2009-2019 were used for this study. The socio-demographic, clinical, microbial, and anti-microbial data retrieved from the patient's health records were used.

RESULTS

We analyzed the sensitivity of gram-negative and gram-positive bacilli reported in HM-FN-BSI patients. Out of the total 512 microorganisms isolated, 416 (81%) were gram-negative bacteria (GNB), 76 (15%) were gram-positive bacteria (GPB) and 20 (4%) were fungi. Furthermore, in 416 GNB, 298 (71.6%) were Enterobacteriaceae sp. among which 121 (41%) were ESBL (Extended Spectrum Beta-Lactamase) resistant to Cephalosporine third generation and Piperacillin-Tazobactam, 54 (18%) were Carbapenem-resistant or multidrug-resistant organism (MDRO). It's noteworthy that the predominant infectious agents in our hospital include E. coli, Klebsiella species, and P. aeruginosa. Throughout the study period, the mortality rate due to BSI was 23%. Risk factors that show a significant correlation with death are age, disease status, mono or polymicrobial BSI and septic shock.

CONCLUSION

Decision pertaining to the usage of antimicrobials for HM-FN-BSI patients is a critical task that relies on the latest pattern of prevalence, treatment resistance, and clinical outcomes. Analysis of the antibiogram of HM-FN-BSI patients in Qatar calls for a reconsideration of currently followed empirical antibiotic therapy towards better infection control and antimicrobial stewardship.

ESBL-producing Enterobacteriaceae in a rural Rwandan community: Carriage among community members, livestock, farm products and environment

OBJECTIVES

Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) are spreading globally. However, respective data from African communities including livestock and environmental specimens are rare. In a rural community of southern Rwanda, we assessed intestinal carriage of ESBL-PE among residents and livestock as well as presence in household specimens and examined associated factors.

METHODS

Samples of humans and livestock (both rectal swabs), soil, water, vegetables and animal products were collected within 312 community households in Sovu, Southern Rwanda. Specimens were screened for ESBL-PE on chromogenic agar, and susceptibility to common antibiotics was determined by disc diffusion assays. Socio-demographic information was collected with questionnaires focusing on the socio-economic background, alimentation, living conditions, hygiene measures and medical history of the participants.

RESULTS

Data and specimens from 312 randomly selected households including 617 human beings, 620 livestock and of approximately each 300 kitchen vegetables, animal products, soil and drinking water were analysed. Overall, 14.8% of 2508 collected samples were positive for ESBL-PE; figures were highest for humans (37.9%) and livestock (15.6%), lower for vegetables (3.8%) and animal products (3.3%), and lowest for soil (1.6%) and water (0.6%). Most detected ESBL-PE were Escherichia coli (93.5%) in addition to Klebsiella pneumoniae (6.5%). Cross-resistance to ampicillin-sulbactam, ciprofloxacin and co-trimoxazole was common. Logistic regression identified increasing age, another ESBL-PE positive household member, prolonged time for fetching water, current diarrhoea and the ability to pay school fees as independent predictors of intestinal ESBL-PE carriage among community members.

CONCLUSIONS

ESBL-PE carriage is common in a rural Rwandan farming community. Carriage in livestock is not associated with human carriage. Associated factors suggest few addressable risk factors. The data indicate that in southern Rwanda, ESBL-PE are no longer primarily hospital-based but circulate in the community.

Development of a prediction model for the acquisition of extended spectrum beta-lactam-resistant organisms in U.S. international travellers

BACKGROUND

Extended spectrum beta-lactamase producing Enterobacterales (ESBL-PE) present a risk to public health by limiting the efficacy of multiple classes of beta-lactam antibiotics against infection. International travellers may acquire these organisms and identifying individuals at high risk of acquisition could help inform clinical treatment or prevention strategies.

METHODS

We used data collected from a cohort of 528 international travellers enrolled in a multicentre US-based study to derive a clinical prediction rule (CPR) to identify travellers who developed ESBL-PE colonization, defined as those with new ESBL positivity in stool upon return to the United States. To select candidate features, we used data collected from pre-travel and post-travel questionnaires, alongside destination-specific data from external sources. We utilized LASSO regression for feature selection, followed by random forest or logistic regression modelling, to derive a CPR for ESBL acquisition.

RESULTS

A CPR using machine learning and logistic regression on 10 features has an internally cross-validated area under the receiver operating characteristic curve (cvAUC) of 0.70 (95% confidence interval 0.69-0.71). We also demonstrate that a four-feature model performs similarly to the 10-feature model, with a cvAUC of 0.68 (95% confidence interval 0.67-0.69). This model uses traveller's diarrhoea, and antibiotics as treatment, destination country waste management rankings and destination regional probabilities as predictors.

CONCLUSIONS

We demonstrate that by integrating traveller characteristics with destination-specific data, we could derive a CPR to identify those at highest risk of acquiring ESBL-PE during international travel.

Gut microbiome perturbation, antibiotic resistance, and Escherichia coli strain dynamics associated with international travel: a metagenomic analysis

BACKGROUND

Culture-based studies have shown that acquisition of extended-spectrum β-lactamase-producing Enterobacterales is common during international travel; however, little is known about the role of the gut microbiome before and during travel, nor about acquisition of other antimicrobial-resistant organisms. We aimed to identify (1) whether the gut microbiome provided colonisation resistance against antimicrobial-resistant organism acquisition, (2) the effect of travel and travel behaviours on the gut microbiome, and (3) the scale and global heterogeneity of antimicrobial-resistant organism acquisition.

METHODS

In this metagenomic analysis, participants were recruited at three US travel clinics (Boston, MA; New York, NY; and Salt Lake City, UT) before international travel. Participants had to travel internationally between Dec 8, 2017, and April 30, 2019, and have DNA extractions for stool samples both before and after travel for inclusion. Participants were excluded if they had at least one low coverage sample (<1 million read pairs). Stool samples were collected at home before and after travel, sent to a clinical microbiology laboratory to be screened for three target antimicrobial-resistant organisms (extended-spectrum β-lactamase-producing Enterobacterales, carbapenem-resistant Enterobacterales, and mcr-mediated colistin-resistant Enterobacterales), and underwent DNA extraction and shotgun metagenomic sequencing. We profiled metagenomes for taxonomic composition, antibiotic-resistant gene content, and characterised the Escherichia coli population at the strain level. We analysed pre-travel samples to identify the gut microbiome risk factors associated with acquisition of the three targeted antimicrobial resistant organisms. Pre-travel and post-travel samples were compared to identify microbiome and resistome perturbation and E coli strain acquisition associated with travel.

FINDINGS

A total of 368 individuals travelled between the required dates, and 296 had DNA extractions available for both before and after travel. 29 travellers were excluded as they had at least one low coverage sample, leaving a final group of 267 participants. We observed a perturbation of the gut microbiota, characterised by a significant depletion of microbial diversity and enrichment of the Enterobacteriaceae family. Metagenomic strain tracking confirmed that 67% of travellers acquired new strains of E coli during travel that were phylogenetically distinct from their pre-travel strains. We observed widespread enrichment of antibiotic-resistant genes in the gut, with a median 15% (95% CI 10-20, p<1 × 10-10) increase in burden (reads per kilobase per million reads). This increase included antibiotic-resistant genes previously classified as threats to public health, which were 56% (95% CI 36-91, p=2 × 10-11) higher in abundance after travel than before. Fluoroquinolone antibiotic-resistant genes were aquired by 97 (54%) of 181 travellers with no detected pre-travel carriage. Although we found that visiting friends or relatives, travel to south Asia, and eating uncooked vegetables were risk factors for acquisition of the three targeted antimicrobial resistant organisms, we did not observe an association between the pre-travel microbiome structure and travel-related antimicrobial-resistant organism acquisition.

INTERPRETATION

This work highlights a scale of E coli and antimicrobial-resistant organism acquisition by US travellers not apparent from previous culture-based studies, and suggests that strategies to control antimicrobial-resistant organisms addressing international traveller behaviour, rather than modulating the gut microbiome, could be worthwhile.

FUNDING

US Centers for Disease Control and Prevention and National Institute of Allergy and Infectious Diseases.

Leveraging the COVID-19 pandemic as a natural experiment to assess changes in antibiotic use and antibiotic-resistant E. coli carriage in semi-rural Ecuador

The coronavirus 2019 (COVID-19) pandemic has had significant impacts on health systems, population dynamics, public health awareness, and antibiotic stewardship, which could affect antibiotic resistant bacteria (ARB) emergence and transmission. In this study, we aimed to compare knowledge, attitudes, and practices (KAP) of antibiotic use and ARB carriage in Ecuadorian communities before versus after the COVID-19 pandemic began. We leveraged data collected for a repeated measures observational study of third-generation cephalosporin-resistant E. coli (3GCR-EC) carriage among children in semi-rural communities in Quito, Ecuador between July 2018 and September 2021. We included 241 households that participated in surveys and child stool sample collection in 2019, before the pandemic, and in 2021, after the pandemic began. We estimated adjusted Prevalence Ratios (aPR) and 95% Confidence Intervals (CI) using logistic and Poisson regression models. Child antibiotic use in the last 3 months declined from 17% pre-pandemic to 5% in 2021 (aPR: 0.30; 95% CI 0.15, 0.61) and 3GCR-EC carriage among children declined from 40 to 23% (aPR: 0.48; 95% CI 0.32, 0.73). Multi-drug resistance declined from 86 to 70% (aPR: 0.32; 95% CI 0.13; 0.79), the average number of antibiotic resistance genes (ARGs) per 3GCR-EC isolate declined from 9.9 to 7.8 (aPR of 0.79; 95% CI 0.65, 0.96), and the diversity of ARGs was lower in 2021. In the context of Ecuador, where COVID-19 prevention and control measures were strictly enforced after its major cities experienced some of the world's the highest mortality rates from SARS-CoV-2 infections, antibiotic use and ARB carriage declined in semi-rural communities of Quito from 2019 to 2021.

Genomic Insights into Global blaCTX-M-55-Positive Escherichia coli Epidemiology and Transmission Characteristics

In recent years, blaCTX-M-55-positive Escherichia coli has been widely reported in multiple locations with an increasing trend in prevalence, yet few studies have comprehensively analyzed the transmission characteristics and epidemiological patterns of blaCTX-M-55-positive E. coli. Here, we constructed a blaCTX-M-55-positive E. coli global genomic data set as completely as possible and explored the epidemiology and potential impact of blaCTX-M-55-positive E. coli on a global scale by high-resolution bioinformatics methods. The results show that blaCTX-M-55-positive E. coli has spread widely worldwide, especially in Asia, with the rich sequence typing (ST) diversity and high proportion of auxiliary genome occupancy indicating a high degree of openness. The phylogenetic tree suggests that blaCTX-M-55-positive E. coli is frequently clonally transmitted between the three human-animal environments and often cotransmitted with fosA, mcr, blaNDM, and tet(X). The stable presence of InclI1 and InclI2 in different hosts from different sources suggests that this part of the plasmid drives the widespread transmission of blaCTX-M-55-positive E. coli. We inductively clustered all blaCTX-M-55 flanking environmental gene structures and obtained five types. Notably, "ISEcp1-blaCTX-M-55-orf477-(Tn2)" and "IS26(IS15DI)-hp-hp-blaCTX-M-55-orf477-hp-blaTEM-IS26-hp-IS26-Tn2" are dominant in "humans" and in "animals and related foods," respectively. Overall, our findings highlight the importance of whole-genome sequencing-based surveillance in exploring the transmission and evolution of blaCTX-M-55-positive E. coli in the context of "One Health," and they serve as a reminder to strengthen the surveillance of blaCTX-M-55-positive E. coli in order to address the potential risk of future large outbreaks. IMPORTANCE CTX-M-55 was first discovered in Thailand in 2004, and today, this enzyme is the most common CTX-M subtype in E. coli of animal origin in China. Thus, blaCTX-M-55-positive E. coli getting widely spread is a growing public health problem. Although prevalence surveys of blaCTX-M-55-positive E. coli in different hosts have been widely reported in recent years, they remain insufficient in "One Health" context and from a global comprehensive perspective. Here, we constructed a genomic database of 2144 blaCTX-M-55-positive E. coli and used bioinformatics methods to resolve the spread and evolution of blaCTX-M-55-positive E. coli. The results suggest a potential risk of rapid transmission of blaCTX-M-55-positive E. coli and that long-term continuous surveillance of blaCTX-M-55-positive E. coli should be emphasized.

Risk Factors for Community Colonization With Extended-Spectrum Cephalosporin-Resistant Enterobacterales (ESCrE) in Botswana: An Antibiotic Resistance in Communities and Hospitals (ARCH) Study

BACKGROUND

The epidemiology of extended-spectrum cephalosporin-resistant Enterobacterales (ESCrE) in low- and middle-income countries (LMICs) is poorly described. Identifying risk factors for ESCrE colonization is critical to inform antibiotic resistance reduction strategies because colonization is typically a precursor to infection.

METHODS

From 15 January 2020 to 4 September 2020, we surveyed a random sample of clinic patients at 6 sites in Botswana. We also invited each enrolled participant to refer up to 3 adults and children. All participants had rectal swabs collected that were inoculated onto chromogenic media followed by confirmatory testing. Data were collected on demographics, comorbidities, antibiotic use, healthcare exposures, travel, and farm and animal contact. Participants with ESCrE colonization (cases) were compared with noncolonized participants (controls) to identify risk factors for ESCrE colonization using bivariable, stratified, and multivariable analyses.

RESULTS

A total of 2000 participants were enrolled. There were 959 (48.0%) clinic participants, 477 (23.9%) adult community participants, and 564 (28.2%) child community participants. The median (interquartile range) age was 30 (12-41) and 1463 (73%) were women. There were 555 cases and 1445 controls (ie, 27.8% of participants were ESCrE colonized). Independent risk factors (adjusted odds ratio [95% confidence interval]) for ESCrE included healthcare exposure (1.37 [1.08-1.73]), foreign travel [1.98 (1.04-3.77]), tending livestock (1.34 [1.03-1.73]), and presence of an ESCrE-colonized household member (1.57 [1.08-2.27]).

CONCLUSIONS

Our results suggest healthcare exposure may be important in driving ESCrE. The strong links to livestock exposure and household member ESCrE colonization highlight the potential role of common exposure or household transmission. These findings are critical to inform strategies to curb further emergence of ESCrE in LMICs.

The highly diverse plasmid population found in Escherichia coli colonizing travellers to Laos and its role in antimicrobial resistance gene carriage

Increased colonization by antimicrobial-resistant organisms is closely associated with international travel. This study investigated the diversity of mobile genetic elements involved with antimicrobial resistance (AMR) gene carriage in extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli that colonized travellers to Laos. Long-read sequencing was used to reconstruct complete plasmid sequences from 48 isolates obtained from the daily stool samples of 23 travellers over a 3 week period. This method revealed a collection of 105 distinct plasmids, 38.1 % (n=40) of which carried AMR genes. The plasmids in this population were diverse, mostly unreported and included 38 replicon types, with F-type plasmids (n=23) the most prevalent amongst those carrying AMR genes. Fine-scale analysis of all plasmids identified numerous AMR gene contexts and emphasized the importance of IS elements, specifically members of the IS6/IS26 family, in the evolution of complex multidrug resistance regions. We found a concerning convergence of ESBL and colistin resistance determinants, with three plasmids from two different F-type lineages carrying bla CTX-M and mcr genes. The extensive diversity seen here highlights the worrying probability that stable new vehicles for AMR will evolve in E. coli populations that can disseminate internationally through travel networks.

Risk-factor analysis for extended-spectrum beta-lactamase-producing Enterobacterales colonization or infection: Evaluation of a novel approach to assess local prevalence as a risk factor

OBJECTIVE

To explore an approach to identify the risk of local prevalence of extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) on ESBL-E colonization or infection and to reassess known risk factors.

DESIGN

Case-control study.

SETTING

Johns Hopkins Health System emergency departments (EDs) in the Baltimore-Washington, DC, region.

PATIENTS

Patients aged ≥18 years with a culture growing Enterobacterales between April 2019 and December 2021. Cases had a culture growing an ESBL-E.

METHODS

Addresses were linked to Census Block Groups and placed into communities using a clustering algorithm. Prevalence in each community was estimated using the proportion of ESBL-E among Enterobacterales isolates. Logistic regression was used to determine risk factors for ESBL-E colonization or infection.

RESULTS

ESBL-E were detected in 1,167 of 11,224 patients (10.4%). Risk factors included a history of ESBL-E in the prior 6 months (aOR, 20.67; 95% CI, 13.71-31.18), exposure to a skilled nursing or long-term care facility (aOR, 1.64; 95% CI, 1.37-1.96), exposure to a third-generation cephalosporin (aOR, 1.79; 95% CI, 1.46-2.19), exposure to a carbapenem (aOR, 2.31; 95% CI, 1.68-3.18), or exposure to a trimethoprim-sulfamethoxazole (aOR, 1.54; 95% CI, 1.06-2.25) within the prior 6 months. Patients were at lower risk if their community had a prevalence <25th percentile in the prior 3 months (aOR, 0.83; 95% CI, 0.71-0.98), 6 months (aOR, 0.83; 95% CI, 0.71-0.98), or 12 months (aOR, 0.81; 95% CI, 0.68-0.95). There was no association between being in a community in the >75th percentile and the outcome.

CONCLUSIONS

This method of defining the local prevalence of ESBL-E may partially capture differences in the likelihood of a patient having an ESBL-E.

The antimicrobial resistance travel tool, an interactive evidence-based educational tool to limit antimicrobial resistance spread

BACKGROUND

International travel has been recognized as a risk factor contributing to the spread of antimicrobial resistance (AMR). However, tools focused on AMR in the context of international travel and designed to guide decision-making are limited. We aimed at developing an evidence-based educational tool targeting both healthcare professionals (HCPs) and international travellers to help prevent the spread of AMR.

METHODS

A literature review on 12 antimicrobial-resistant bacteria (ARB) listed as critical and high tiers in the WHO Pathogen Priority List covering four key areas was carried out: AMR surveillance data; epidemiological studies reporting ARB prevalence data on carriage in returning travellers; guidance documents reporting indications on screening for ARB in returning travellers and recommendations for ARB prevention for the public. The evidence, catalogued at country-level, provided the content for a series of visualizations that allow assessment of the risk of AMR acquisition through travel.

RESULTS

Up to January 2021, the database includes data on: (i) AMR surveillance for 2.018.241 isolates from 86 countries; (ii) ARB prevalence of carriage from 11.679 international travellers and (iii) 15 guidance documents published by major public health agencies. The evidence allowed the development of a consultation scheme for the evaluation of risk factors, prevalence of carriage, proportion and recommendations for screening of AMR. For the public, pre-travel practical measures to minimize the risk of transmission were framed.

CONCLUSIONS

This easy-to-use, annually updated, freely accessible AMR travel tool (https://epi-net.eu/travel-tool/overview/), is the first of its kind to be developed. For HCPs, it can provide a valuable resource for teaching and a repository that facilitates a stepwise assessment of the risk of AMR spread and strengthen implementation of optimized infection control measures. Similarly, for travellers, the tool has the potential to raise awareness of AMR and outlines preventive measures that reduce the risk of AMR acquisition and spread.

Mortality Risk Factors and Prognostic Analysis of Patients with Multi-Drug Resistant Enterobacterales Infection

Background

The data from the China Network Antibacterial Surveillance Center (http://www.chinets.com) showed that the prevalence of Escherichia coli (E. coli), Klebsiella pneumoniae (KP), and Enterobacter cloacae (ecl), was 18.96%, 14.12%, and 2.74% in 2022, respectively. The resistance rates of E. coli and KP to 3rd or 4th generation cephalosporins were 51.7% and 22.1%, to carbapenems was 1.7% and 3.9%, to quinolones was 55.9% in Shanxi. The generation of extended-spectrum beta-lactamases (ESBLs) is a major mechanism resulting in drug resistance in Enterobacterales. To determine the mortality risk factors of multi-drug resistant Enterobacterales (MDRE) and multi-drug resistant Klebsiella pneumoniae (MDR-KP) infection.

Methods

91 MDR strains from 91 patients were collected from 2015 to 2019 in the second hospital of Shanxi Medical University. The mortality risk factors for the MDRE infections and clinical outcomes were analyzed by univariable and multivariable analysis. The independent predictors of 30-day mortality were analyzed through the Cox regression analysis including the variables with a value <0.2.

Results

The majority of patients were admitted to ICUs. Pulmonary infection was a major infection (43.96%, 40/91). Thirty-three (36.26%, 33/91) strains of MDR-KP were only detected in 2018. The proportion of multi-drug resistant Escherichia coli (MDR E. coli) and multi-drug resistant Enterobacter cloacae (MDR ecl) were 16.48% (15/91) and 17.58% (16/91), respectively. The presence of cerebrovascular diseases (OR, 4.046; 95%Cl, 1.434–11.418; P=0.008) and central venous catheterization (OR, 4.543; 95%Cl, 1.338–15.425; P=0.015) were associated with mortality in patients with MDRE infections. Endotracheal intubation (OR, 4.654; 95%Cl, 1.5–14.438; P=0.008) was an independent mortality risk factor for patients infected with MDR-KP strains. Patients who received aminoglycoside antibiotics (P=0.057) had a higher 30-day survival rate. The β-lactam antibiotics were the major agent in the clinic.

Conclusion

This study implies that patients with cerebrovascular diseases, central venous catheterization, and endotracheal intubation are at risk of carrying MDR isolates.

Carriage Duration and Household Transmission of Enterobacterales Producing Extended-Spectrum Beta-Lactamase in the Community: A Systematic Review and Meta-Analysis

An attributing factor to Enterobacterales producing extended-spectrum beta-lactamase (ESBL-E) community spread is human-to-human transmission. This systematic review and meta-analysis aimed to estimate the duration of ESBL-E carriage in the community and the rate of household transmission. Literature search was performed on PubMed, EMBASE, and Scopus. Dose-response meta-analysis was planned to model the proportion of ESBL-E carriers and household transmission over time. Twenty-six studies (n = 2,505 participants) were included. The median carriage duration was 2 months. Approximately 22% (95% confidence interval: 16-28) had persistent carriage after 12 months. Travelers had significantly shorter carriage (median 1-2 months) than discharged hospital patients (median 6 months) at all measured time points. There were insufficient data to robustly meta-analyze household transmission. Nonetheless, five longitudinal studies reported 18.4% to 35.2% of contacts acquired ESBL-E within 4 to 36 months from hospital discharge of index case. Transmission events from travelers to their contacts appeared lower. Travelers with travel-acquired ESBL-E had significantly faster decolonization rate than discharged patients, suggesting that travel-associated import of multidrug-resistant pathogen may have limited contribution to community transmission of ESBL-E. The substantial prevalence of persistent carriers warrant consideration for additional measures to mitigate exposure risk of ESBL-E from discharged patients in the community and from readmitting patients in the hospital.

International Travel as a Risk Factor for Carriage of Extended-Spectrum β-Lactamase-Producing Escherichia coli in a Large Sample of European Individuals—The AWARE Study

Antibiotic resistance (AR) is currently a major threat to global health, calling for a One Health approach to be properly understood, monitored, tackled, and managed. Potential risk factors for AR are often studied in specific high-risk populations, but are still poorly understood in the general population. Our aim was to explore, describe, and characterize potential risk factors for carriage of Extended-Spectrum Beta-Lactamase-resistant Escherichia coli (ESBL-EC) in a large sample of European individuals aged between 16 and 67 years recruited from the general population in Southern Germany, the Netherlands, and Romania. Questionnaire and stool sample collection for this cross-sectional study took place from September 2018 to March 2020. Selected cultures of participants’ stool samples were analyzed for detection of ESBL-EC. A total of 1183 participants were included in the analyses: 333 from Germany, 689 from the Netherlands, and 161 from Romania. Travels to Northern Africa (adjusted Odds Ratio, aOR 4.03, 95% Confidence Interval, CI 1.67–9.68), Sub-Saharan Africa (aOR 4.60, 95% CI 1.60–13.26), and Asia (aOR 4.08, 95% CI 1.97–8.43) were identified as independent risk factors for carriage of ESBL-EC. Therefore, travel to these regions should continue to be routinely asked about by clinical practitioners as possible risk factors when considering antibiotic therapy.

Bacterial travellers' diarrhoea: A narrative review of literature published over the past 10 years

Travellers' diarrhoea (TD) is the most frequent illness experienced by international travellers to lower-income countries with bacterial agents considered to account for 80-90% of cases. In this review, we summarise evidence published on bacterial TD over the past 10 years, focusing on the epidemiology and aetiology of TD. Diarrhoeagenic Escherichia coli (DEC) continue to be the most commonly implicated bacteria in TD, although Enteropathogenic E. coli (EPEC) and Enteroaggregative E. coli (EAEC) now appear to be predominant where Enterotoxigenic E. coli (ETEC) was previously considered most prevalent globally. Where fluroquinolone resistance had primarily been documented for Campylobacter in Southeast Asia, widespread resistance has been observed in most regions of the world for multiple enteropathogens, including Shigella, Salmonella, ETEC and EAEC. Implementation of novel molecular methods for pathogen detection has led to identification of bacterial pathogens, including Clostridium difficile (with and without the use of prior antibiotics), Arcobacter species and Bacteroides fragilis, as aetiological agents in TD. The widespread resistance to first-line antibiotics in multiple bacterial enteropathogens warrants continued surveillance and re-evaluation of current treatment practices. Further investigations are required to determine the prevalence and geographical distribution of bacterial enteropathogens that have been more recently implicated in TD.

Overcoming the rising incidence and evolving mechanisms of antibiotic resistance by novel drug delivery approaches - An overview

Antimicrobial resistance is a normal evolutionary process for microorganisms. Antibiotics exerted accelerated selective pressure that hasten bacterial resistance through mutation, and acquisition external genes. These genes often carry multiple antibiotic resistant determinants allowing the recipient microbe an instant "super-bug" status. The extent of Antimicrobial Resistance (AMR) has reached a level of global crisis, existing antimicrobials are no long effective in treating infections caused by AMR pathogens. The great majority of clinically available antimicrobial agents are administered through oral and intra-venous routes. Overcoming antibacterial resistance by novel drug delivery approach offered new hopes, particularly in the treatment of AMR pathogens in sites less assessible through systemic circulation such as the lung and skin. In the current review, we will revisit the mechanism and incidence of important AMR pathogens. Finally, we will discuss novel drug delivery approaches including novel local antibiotic delivery systems, hybrid antibiotics, and nanoparticle-based antibiotic delivery systems.

Extended-spectrum beta-lactamase-producing strains among diarrhoeagenic Escherichia coli-prospective traveller study with literature review

BACKGROUND

Antibiotics are no longer the primary approach for treating all travellers' diarrhoea (TD): most cases resolve without antibiotics and using them predisposes to colonization by multidrug-resistant bacteria. Data are accumulating on increasing resistance among TD pathogens, yet research into the most common agents, diarrhoeagenic Escherichia coli (DEC), remains limited.

METHODS

A total of 413 travellers to the (sub)tropics were analyzed for travel-acquired diarrhoeal pathogens and ESBL-PE. To identify ESBL-producing DEC, ESBL-producing E. coli (ESBL-EC) isolates were subjected to multiplex qPCR for various DEC pathotypes: enteroaggregative (EAEC), enteropathogenic (EPEC), enterotoxigenic (ETEC), enteroinvasive (EIEC) and enterohaemorrhagic (EHEC) E. coli.For a literature review, we screened studies among travellers and locals in low- and middle-income countries (LMICs) on the frequency of ESBL-producing DEC, and among travellers, also DEC with resistance to ciprofloxacin, azithromycin, and rifamycin derivatives.

RESULTS

Our rate of ESBL-EC among all DEC findings was 2.7% (13/475); among EAEC 5.7% (10/175), EPEC 1.1% (2/180), ETEC 1.3% (1/80) and EHEC (0/35) or EIEC 0% (0/5). The literature search yielded three studies reporting ESBL-EC frequency and thirteen exploring resistance to TD antibiotics among travel-acquired DEC. For EAEC and ETEC, the ESBL-EC rates were 10-13% and 14-15%, resistance to fluoroquinolones 0-42% and 0-40%, azithromycin 0-29% and 0-61%, and rifaximin 0% and 0-20%. The highest rates were from the most recent collections. Proportions of ESBL-producing DEC also appear to be increasing among locals in LMICs and even carbapenemase-producing DEC were reported.

CONCLUSION

ESBL producers are no longer rare among DEC, and the overall resistance to various antibiotics is increasing. The data predict decreasing efficacy of antibiotic treatment, threatening its benefits, for disadvantages still prevail when efficacy is lost.

High levels of gut carriage of antimicrobial-resistant Escherichia coli in community settings in Rio de Janeiro, Brazil

The prevalence and risk factors for gut carriage of antimicrobial-resistant Escherichia coli among individuals living in the community in Rio de Janeiro, Brazil, are unknown. The aim of this study was to determine the prevalence of colonization with antimicrobial-resistant E. coli, including isolates producing ESBL and harboring plasmid-mediated quinolone resistant (PMQR) genes in this community. We performed a cross-sectional study and analyzed fecal specimens of individuals attending outpatient clinics in the city from January 2015 to July 2019. We investigated susceptibility to antimicrobial agents by disc diffusion tests and used PCR to determine ESBL types, PMQR, and the virulence genes that characterize an isolate as extraintestinal pathogenic E. coli (ExPEC). Among the 623 subjects, 212 (34%) carried an isolate resistant to at least one of the tested antimicrobial agents, with the highest frequencies of resistance to ampicillin (26%), trimethoprim-sulfamethoxazole (19%), cefazolin (14%), and ciprofloxacin (CIP, 9%). In addition, 13% (81) of subjects carried a multidrug-resistant-E.coli (MDR-E), including 47 (8% of all isolates) ESBL-producing E. coli (ESBL-E), mainly of CTX-M-8 (15, 32%) and CTX-M-15 (9, 20%) types. PMQR genes were present in 7% (42) of all isolates, including 60% (32) of the 53 resistant to CIP. Previous use of antimicrobial agents, particularly fluoroquinolones, was a risk factor for colonization with MDR-E (25%, 20/81 vs 13%, 70/542, p = 0.01), ESBL-E (28%, 13/47, vs 13%, 77/576, p = 0.01), and resistance to CIP (26%, 14/53, vs 12%, 70/570, p = 0.01). The most pathogenic phylogroups B2, C, and D were 37% of the MDR-E, 30% of the ESBL-E, 38% of the CIP-resistant, and 31% of PMQR gene carrying E. coli isolates. We show that carriage of MDR-E (mostly ESBL-E) reached high levels in the community in Rio de Janeiro, increased by the selection of antimicrobial agents. Much of the resistant E. coli isolates are potential pathogenic strains. The widespread use of antimicrobial agents during the COVID-19 pandemic in Brazil may have worsened this picture.

Carriage of ESBL-producing Enterobacterales in wastewater treatment plant workers and surrounding residents - the AWARE Study

To investigate whether wastewater treatment plant (WWTP) workers and residents living in close proximity to a WWTP have elevated carriage rates of ESBL-producing Enterobacterales, as compared to the general population. From 2018 to 2020, we carried out a cross-sectional study in Germany, the Netherlands, and Romania among WWTP workers (N = 344), nearby residents (living ≤ 300 m away from WWTPs; N = 431) and distant residents (living ≥ 1000 m away = reference group; N = 1165). We collected information on potential confounders via questionnaire. Culture of participants' stool samples was performed with ChromID®-ESBL agar plates and species identification with MALDI-TOF-MS. We used logistic regression to estimate the odds ratio (OR) for carrying ESBL-producing E. coli (ESBL-EC). Sensitivity analyses included stratification by country and interaction models using country as secondary exposure. Prevalence of ESBL-EC was 11% (workers), 29% (nearby residents), and 7% (distant residents), and higher in Romania (28%) than in Germany (7%) and the Netherlands (6%). Models stratified by country showed that within the Romanian population, WWTP workers are about twice as likely (aOR = 2.34, 95% CI: 1.22-4.50) and nearby residents about three times as likely (aOR = 3.17, 95% CI: 1.80-5.59) to be ESBL-EC carriers, when compared with distant residents. In stratified analyses by country, we found an increased risk for carriage of ESBL-EC in Romanian workers and nearby residents. This effect was higher for nearby residents than for workers, which suggests that, for nearby residents, factors other than the local WWTP could contribute to the increased carriage.

Temporal and structural patterns of extended-spectrum cephalosporin-resistant Klebsiella pneumoniae incidence in Swiss hospitals

BACKGROUND

Routine surveillance data revealed increasing rates of invasive extended-spectrum cephalosporin-resistant Klebsiella pneumoniae (ESCR-KP) in Switzerland, from 1.3% in 2004 to 8.5% in 2019.

AIM

The main aim of this study was to understand the causes of this recent trend, specifically to identify predictors affecting the incidence of invasive ESCR-KP infections in Switzerland.

METHODS

A retrospective observational multi-centre study was conducted in 21 Swiss hospitals over a period of 11 years (2009-2019). Potential predictor variables for the incidence of invasive ESCR-KP infections were studied with a multiple linear regression model. In an additional analysis, the overall ESCR-KP incidence (all sample sites) was investigated.

FINDINGS

An increasing incidence of invasive ESCR-KP infections from 0.01 to 0.04 patients per 1000 bed-days was observed between 2009 and 2019 and confirmed by multiple linear regression analysis (P < 0.01). ESCR-KP incidence was higher in university hospitals (P < 0.01) and in the French-speaking region than in the German-speaking region (P < 0.01). There was no association with antibiotic consumption. Analysing the overall ESCR-KP incidence (all sample sites) revealed high variability between university hospitals, mainly due to a high proportion of patients with screening isolates at Geneva University Hospital (50% of patients with ESCR-KP).

CONCLUSION

The incidence of invasive ESCR-KP infections increased in Switzerland between 2009 and 2019 and was not associated with antibiotic consumption. Our findings indicate that, in this low-incidence setting, structural factors such as the hospital type and the linguistic region play a more important role in relation to ESCR-KP incidence than the hospital's antibiotic consumption.

Risk factors for colonization with multiple species of extended-spectrum beta-lactamase producing Enterobacterales: a case-case-control study

BACKGROUND

Approximately 11% of patients colonized with extended-spectrum beta-lactamase producing Enterobacterales (ESBL-PE) are colonized with more than one ESBL-producing species. We investigated risk factors associated with colonization with multiple ESBL-PE species.

METHODS

We performed a case-case-control study at the University Hospital Basel, Switzerland, including hospitalized patients colonized with ESBL-PE between 01/2008 and 12/2018. Patients colonized with multiple species of ESBL-PE during the same hospitalization were assigned to group 1. Group 2 consisted of patients with ESBL-PE and a newly acquired ESBL-PE-species identified during subsequent hospitalization. Controls (i.e., group 3) were patients with only one species of ESBL-PE identified over multiple hospitalizations. Controls were frequency-matched 3:1 to group 2 cases according to time-at-risk (i.e., days between ESBL-PE detection during first and subsequent hospitalizations) to standardize the duration of colonization. ESBL was identified with phenotypic assay and the presence of ESBL genes was confirmed by whole genome sequencing.

RESULTS

Among 1559 inpatients, 154 cases met eligibility criteria (67 in group 1, 22 in group 2, 65 in group 3). International travel within the previous 12 months (OR 12.57, 95% CI 3.48-45.45, p < 0.001) and antibiotic exposure within the previous 3 months (OR 2.96, 95% CI 1.37-6.41, p = 0.006) were independently associated with co-colonization with multiple ESBL-PE species. Admission from another acute-care facility was the only predictor of replacement of one ESBL-PE species with another during subsequent hospitalizations (OR 6.02, 95% CI 1.15-31.49, p = 0.003).

CONCLUSION

These findings point to strain-related factors being the main drivers of co-colonization with different ESBL-PE and may support stratification of infection prevention and control measures according to ESBL-PE species/strains.

New insights and antimicrobial stewardship opportunities in viral pneumonia: five lung ultrasound cases

Background

Antimicrobial stewardship is crucial to avoid antimicrobial resistance in microbes and adverse drug effects in patients. In respiratory infections, however, viral pneumonia is difficult to distinguish from bacterial pneumonia, which explains the overuse of antibiotic therapy in this indication.

Cases

Five cases of lung consolidation are presented. Lung ultrasound, in conjunction with procalcitonin levels, were used to exclude or corroborate bacterial pneumonia.

Conclusion

Lung ultrasound is easy to learn and perform and is helpful in guiding diagnosis in unclear cases of pneumonia and may also offer new insights into the spectrum of certain virus diseases. The use of lung ultrasound can raise awareness in clinicians of the need for antimicrobial stewardship and may help to avoid the unnecessary use of antibiotics.

Supplementary Information

The online version of this article (10.1007/s00508-021-01946-4) contains supplementary material, which is available to authorized users.

Import of multidrug-resistant bacteria from abroad through interhospital transfers, Finland, 2010-2019

Background

While 20–80% of regular visitors to (sub)tropical regions become colonised by extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE), those hospitalised abroad often also carry other multidrug-resistant (MDR) bacteria on return; the rates are presumed to be highest for interhospital transfers.

Aim

This observational study assessed MDR bacterial colonisation among patients transferred directly from hospitals abroad to Helsinki University Hospital. We investigated predisposing factors, clinical infections and associated fatalities.

Methods

Data were derived from screening and from diagnostic samples collected between 2010 and 2019. Risk factors of colonisation were identified by multivariable analysis. Microbiologically verified symptomatic infections and infection-related mortality were recorded during post-transfer hospitalisation.

Results

Colonisation rates proved highest for transfers from Asia (69/96; 71.9%) and lowest for those within Europe (99/524; 18.9%). Of all 698 patients, 208 (29.8%) were colonised; among those, 163 (78.4%) carried ESBL-PE, 28 (13.5%) MDR Acinetobacter species, 25 (12.0%) meticillin-resistant Staphylococcus aureus, 25 (12.0%) vancomycin-resistant Enterococcus, 14 (6.7%) carbapenemase-producing Enterobacteriaceae, and 12 (5.8%) MDR Pseudomonas aeruginosa; 46 strains tested carbapenemase gene-positive. In multivariable analysis, geographical region, intensive care unit (ICU) treatment and antibiotic use abroad proved to be risk factors for colonisation. Clinical MDR infections, two of them fatal (1.0%), were recorded for 22 of 208 (10.6%) MDR carriers.

Conclusions

Colonisation by MDR bacteria was common among patients transferred from foreign hospitals. Region of hospitalisation, ICU treatment and antibiotic use were identified as predisposing factors. Within 30 days after transfer, MDR colonisation manifested as clinical infection in more than 10% of the carriers.

Antimicrobial-resistant bacteria in international travelers

PURPOSE OF REVIEW

Antimicrobial resistance (AMR) in bacteria poses a major risk to global public health, with many factors contributing to the observed increase in AMR. International travel is one recognized contributor. The purpose of this review is to summarize current knowledge regarding the acquisition, carriage and spread of AMR bacteria by international travelers.

RECENT FINDINGS

Recent studies have highlighted that travel is an important risk factor for the acquisition of AMR bacteria, with approximately 30% of studied travelers returning with an acquired AMR bacterium. Epidemiological studies have shown there are three major risk factors for acquisition: travel destination, antimicrobial usage and travelers' diarrhea (TD). Analyses have begun to illustrate the AMR genes that are acquired and spread by travelers, risk factors for acquisition and carriage of AMR bacteria, and local transmission of imported AMR organisms.

SUMMARY

International travel is a contributor to the acquisition and dissemination of AMR organisms globally. Efforts to reduce the burden of AMR organisms should include a focus on international travelers. Routine genomic surveillance would further elucidate the role of international travel in the global spread of AMR bacteria.

Decreasing proportion of extended-spectrum beta-lactamase among E. coli infections during the COVID-19 pandemic in France

OBJECTIVES

We investigated the impact of the COVID-19 and national pandemic response on the epidemiology of Extended Spectrum Beta-Lactamase producing E. coli (ESBL-E.coli) in France.

METHODS

Individual microbiology records from clinical laboratories were analyzed between 1 January 2019 to 31 December 2020. The ESBL-E.coli rates from clinical samples of patients in primary care and nursing home residents were compared before and after the general lockdown in March 2020, according to demographic and geographical characteristics. Interrupted time series analyses were performed to detect measurable changes in the trend of ESBL-E.coli rates.

RESULTS

Records covering 793,954 E. coli isolates from 1022 clinical laboratories were analyzed. In primary care, 3.1% of E. coli isolates from clinical samples were producing ESBL before March 2020 and 2.9% since May 2020 (p < 0.001). The proportion of ESBL-E.coli decreased significantly among urine cultures, females, age categories 5-19, 40-64, > 65 year-old, and in the North, West, East and South-East regions. In nursing home, the ESBL-E.coli rate was 9.3% (monthly rate min-max: 6.5-10.5%) before March 2020 and 8.3% (7.2-9.1%) since May 2020 (p < 0.001). The reduction rate accelerated from -0.04%/month to -0.22%/month from May 2020 (p < 0.001).

CONCLUSION

Investigation of factors that led to the decreased proportion of ESBL-E.coli during the COVID-19 pandemic is urgently needed.

Multidrug-Resistant Lineage of Enterotoxigenic Escherichia coli ST182 With Serotype O169:H41 in Airline Waste

Enterotoxigenic Escherichia coli (ETEC) is the primary aetiologic agent of traveller’s diarrhoea and a significant cause of diarrhoeal disease and death in developing countries. ETEC O169:H41 strains are known to cause both traveller’s diarrhoea and foodborne outbreaks in developed countries and are cause for concern. Here, whole-genome sequencing (WGS) was used to assemble 46 O169:H41 (ST182) E. coli draft genomes derived from two airplane waste samples sourced from a German international airport. The ST182 genomes were compared with all 84 publicly available, geographically diverse ST182 genomes to construct a core genome-based phylogenetic tree. ST182 isolates were all phylogroup E, the majority serotype O169:H41 (n = 121, 93%) and formed five major clades. The airplane waste isolates differed by an average of 15 core SNPs (range 0–45) but their accessory genome content was diverse. While uncommon in other ST182 genomes, all airplane-derived ST182 isolates carried: (i) extended-spectrum β-lactamase gene bla_CTX–M–15 notably lacking the typical adjacent ISEcp1; (ii) qnrS1 and the S83L mutation in gyrA, both conferring resistance to fluoroquinolones; and (iii) a class 1 integron structure (IS26-intI1_Δ648-dfrA17-aadA5-qacEΔ1-sul1-ORF-srpC-padR-IS6100-mphR-mrx-mphA-IS26) identified previously in major extraintestinal pathogenic E. coli STs but not in ETEC. ST182 isolates carried ETEC-specific virulence factors STp + CS6. Adhesin/invasin tia was identified in 89% of aircraft ST182 isolates (vs 23%) and was located on a putative genomic island within a hotspot region for various insertions including PAI I₅₃₆ and plasmid-associated transposons. The most common plasmid replicons in this collection were IncFII (100%; F2:A-:B-) and IncB/O/K/Z (89%). Our data suggest that potentially through travel, E. coli ST182 are evolving a multidrug-resistant profile through the acquisition of class 1 integrons and different plasmids.

Prevalence of multidrug-resistant and extended-spectrum beta-lactamase-producing Escherichia coli in urban community wastewater

Antibiotic resistance (ABR) and the spread of multidrug-resistant and extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli via wastewater to environmental compartments are of rapidly growing global health concern. Health care facilities, industries and slaughterhouses discharge high loads of ABR bacteria with their wastewater. However, the general community is often the biggest indirect discharger. Yet, research focusing explicitly on this important diffuse source is rather scarce raising questions about variations in the occurrence of ESBL-producing E. coli in wastewater from different communities and over time. Between April 2019 and March 2020, wastewater from three socio-spatially different districts in the Ruhr Metropolis, Germany, and the receiving wastewater treatment plant was sampled monthly and analysed for the occurrence of ESBL-producing E. coli via culture-based methods. Isolates were validated with matrix assisted laser desorption ionization time of flight mass spectrometry and antibiotic resistance profiles were analysed via microdilution. Results were interpreted using the European Committee on Antimicrobial Susceptibility Testing criteria. The German Commission for Hospital Hygiene and Infection Prevention criteria were used for multidrug-resistance categorization. Phenotypic ESBL-producing E. coli could be isolated from every wastewater sample demonstrating that the general community is an important indirect discharger. The socio-spatially disadvantaged area displayed higher absolute loads of ESBL-producing E. coli compared to the other two areas, as well as higher adjusted loads for domestic discharge and inhabitants, particularly during winter, indicating a higher ABR burden. Thirty-two isolates (28.6%) were characterized as multidrug-resistant Gram-negative bacteria (3MRGN). Resistance profiles varied only for those antibiotics, which can be administered in outpatient care. Resistance levels tended to be around 10% lower in the socio-spatially advantaged area. This study shows that spatial and seasonal influences regarding the occurrence of ESBL-producing E. coli in wastewater from socio-spatially different communities are identifiable.

Screening for multi-drug-resistant Gram-negative bacteria: what is effective and justifiable?

Effectiveness is a key criterion in assessing the justification of antibiotic resistance interventions. Depending on an intervention’s effectiveness, burdens and costs will be more or less justified, which is especially important for large scale population-level interventions with high running costs and pronounced risks to individuals in terms of wellbeing, integrity and autonomy. In this paper, we assess the case of routine hospital screening for multi-drug-resistant Gram-negative bacteria (MDRGN) from this perspective. Utilizing a comparison to screening programs for Methicillin-Resistant Staphylococcus aureus (MRSA) we argue that current screening programmes for MDRGN in low endemic settings should be reconsidered, as its effectiveness is in doubt, while general downsides to screening programs remain. To accomplish justifiable antibiotic stewardship, MDRGN screening should not be viewed as a separate measure, but rather as part of a comprehensive approach. The program should be redesigned to focus on those at risk of developing symptomatic infections with MDRGN rather than merely detecting those colonised.

Systematic Review and Meta-Analyses Assessment of the Clinical Efficacy of Bismuth Subsalicylate for Prevention and Treatment of Infectious Diarrhea

BACKGROUND

A large number of studies have evaluated the pharmacology, safety, and/or efficacy of bismuth subsalicylate for the relief of common gastrointestinal symptoms, diarrhea and vomiting due to acute gastroenteritis. In addition, short-term (48 h) medication with bismuth subsalicylate is known to be effective against infectious gastroenteritis such as travelers' diarrhea.

AIMS

Previous studies have documented the bacteriostatic/bactericidal effects of bismuth subsalicylate against a variety of pathogenic gastrointestinal bacteria. However, meta-analyses of the clinical efficacy of bismuth subsalicylate for both prevention and treatment of travelers' diarrhea have not yet been published.

METHODS

A total of 14 clinical studies (from 1970s to 2007) comprised the core data used in this assessment of efficacy of bismuth subsalicylate against infectious (including travelers') diarrhea. These studies allowed for statistical meta-analyses regarding prevention (three travelers' diarrhea studies) and treatment of infectious diarrhea (11 studies [five travelers' diarrhea]).

RESULTS

The results show that subjects treated with bismuth subsalicylate for up to 21 days have 3.5 times greater odds of preventing travelers' diarrhea compared with placebo (95% CI 2.1, 5.9; p < 0.001). In addition, subjects with infectious diarrhea treated with bismuth subsalicylate had 3.7 times greater odds of diarrhea relief (recorded on diaries as subjective symptomatic improvement) compared to those receiving placebo (95% CI 2.1, 6.3; p < 0.001).

CONCLUSIONS

This systematic review and meta-analysis suggests that bismuth subsalicylate can be beneficial for those at risk or affected by food and waterborne diarrheal disease such as traveler's (infectious) diarrhea, and may decrease the risk of inappropriate antibiotic utilization.

Colonization with selected antibiotic resistant bacteria among a cohort of Sri Lankan university students

Background

Antibiotic Resistance is an imminent global public health threat. Antibiotic resistance emerged in healthcare settings and has now moved on to the community settings.

This study was conducted to identify the rates of asymptomatic colonization with selected antibiotic resistant organisms, (Methicillin Resistant Staphylococcus aureus (MRSA), Extended Spectrum Beta Lactamase (ESBL) producing Escherichia coli and Klebsiella spp and carbapenem resistant E.coli and Klebsiella spp) - among a group of university students in Sri Lanka. Identification of genetic determinants of MRSA and ESBL was an additional objective of the study.

Methods

A self - collected nasal swab and a peri-rectal swab collected after passing stools were obtained. Routine microbiological methods were used for the isolation S.aureus from the nasal swab and E.coli and Klebsiella species from the peri-rectal swab. Antibiotic sensitivity testing was performed as recommended by clinical and laboratory standard institute (CLSI).

Three (3) genes that are responsible for ESBL production; bla_CTX-M, bla_SHV, and bla_TEM were tested using previously described primers and PCR procedures. Identification of MecA and PVL genes attributed to MRSA was also done with PCR.

Results

A total of 322 participants between 21 and 28 years were recruited representing 5 different faculties of study. Seventy one (22.0%) were colonized with S.aureus and 14 among them with MRSA, making the MRSA colonization rate of 4.3%. Forty five (15%) of the participants were colonized with an ESBL producing E.coli or Klebsiella spp. No one was colonized with carbapenem resistant E.coli or Klebsiella species. Of the 45 ESBL producers the commonest genetic determinant identified was bla_CTX-M (n = 36), while 16 isolates had bla_TEM and 7 had bla_SHV. Similarly, of the 14 isolates identified as MRSA, 3 (21.4%) were found to be PVL positive while 11 (78.6%) were MecA positive.

Conclusions

A high rate of colonization with ESBL producing E.coli and Klebsiella species was noted in our study group.

Risk factors for and management of metronidazole-refractory giardiasis in international travellers: A retrospective analysis

BACKGROUND

Giardia lamblia is a common cause of diarrhoea in returning travellers. Failure of the recommended first-line treatment, metronidazole, has frequently been observed. Recommendations for treatment of metronidazole-refractory giardiasis lack clarity and evidence.

METHODS

We conducted a retrospective data analysis of returned travellers with confirmed giardiasis at the Bernhard-Nocht-Clinic in Hamburg, Germany, between 2007 and 2016.

RESULTS

We identified 339 cases of giardiasis, mostly acquired in South Asia (n = 157). 308 patients received metronidazole as first-line treatment, leading to treatment failure in 93 cases. Statistical analysis suggested by far the highest risk of metronidazole treatment failure for travellers returning from South Asia (Odds Ratio 8.73). Second-line therapy consisted of various different therapy regimens. Combination therapy as second-line treatment seemed to be more effective than monotherapy. A repeat course of metronidazole proved to be futile.

CONCLUSION

This study reveals a strikingly low effectiveness of metronidazole, especially in patients returning from South Asia. Second-line treatment showed inconsistency of regimens and yielded unsatisfactory results. These findings require reconsideration of treatment strategies for giardiasis. Large prospective trials are urgently needed to assess new first-line treatment options and to help implement advice for effective, agreed second-line treatment strategies. Translational projects should be created to link the understanding of resistance mechanisms with epidemiological data and clinical outcome.

Plasmids conferring resistance to extended-spectrum beta-lactamases including a rare IncN+IncR multireplicon carrying blaCTX-M-1 in Escherichia coli recovered from migrating barnacle geese ( Branta leucopsis)

Background: Increasing antimicrobial resistance (AMR) is a global threat and wild migratory birds may act as mediators of resistant bacteria across country borders. Our objective was to study extended-spectrum beta-lactamase (ESBL) and plasmid-encoded AmpC (pAmpC) producing Escherichia coli in barnacle geese using whole genome sequencing (WGS) and to identify plasmids harboring bla genes. Methods: Barnacle geese feces (n=200) were collected during fall 2017 and spring 2018 from an urban area in Helsinki, Finland. ESBL/AmpC-producing E. coli were recovered from nine samples (4.5%) and isolates were subjected to WGS on both short- and long-read sequencers, enabling hybrid assembly and determination of the genomic location of bla genes. Results: A rare multireplicon IncN+IncR was recovered from one isolate carrying bla CTX-M-1 in addition to aadA2b, lnu(F), and qnrS1. Moreover, rarely detected IncY plasmids in two isolates were found to harbor multiple resistance genes in addition to the human-associated bla CTX-M-15. Poultry-associated bla CMY-2 was identified from the widely distributed IncI1 and IncK plasmids from four different isolates. One isolate harbored an IncI1 plasmid with bla CTX-M-1 and flor. A chromosomal point mutation in the AmpC promoter was identified in one of the isolates. WGS analysis showed isolates carried multiple resistance and virulence genes and harbored multiple different plasmid replicons in addition to bla-carrying plasmids. Conclusions: Our findings suggest that wild migratory birds serve as a limited source of ESBL/AmpC-producing E. coli and may act as disseminators of the epidemic plasmid types IncI1 and IncK but also rarely detected plasmid types carrying multidrug resistance. Human and livestock-associated ESBL enzyme types were recovered from samples, suggesting a potential for interspecies transmission. WGS offers a thorough method for studying AMR from different sources and should be implemented more widely in the future for AMR surveillance and detection. Understanding plasmid epidemiology is vital for efforts to mitigate global AMR spread.

Role of gut microbiota in travel-related acquisition of extended spectrum β-lactamase-producing Enterobacteriaceae

BACKGROUND

International travel could facilitate the spread of antimicrobial-resistant bacteria including extended spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E). Previous studies, which attempted to understand the role of gut microbiota in the acquisition of antimicrobial resistant bacteria during international travels, are limited to western travellers.

METHODS

We established a prospective cohort of 90 Hong Kong travellers to investigate gut microbiota determinants and associated risk factors for the acquisition of ESBL-E. Baseline characteristics and travel-associated risk factors were gathered through questionnaires. Faecal samples were collected in 3-4 days before and after travel. Antimicrobial susceptibility of ESBL-E isolates was tested, and gut microbiota were profiled by 16S rDNA amplicon sequencing. Non-parametric tests were used to detect potential associations, and logistic regression models were used to quantify the associations. Random forest models were constructed to identify microbial predictors for ESBL-E acquisition.

RESULTS

In total, 49 (54.4%) participants were tested negative for ESBL-E colonization before travel and were followed up after travel. A total of 60 ESBL-E isolates were cultured from 20 (40.8%) participants. Having low Actinobacteria richness and low abundance of short-chain fatty acid-producing bacteria in the gut microbiota before travel increased the risk of acquiring ESBL-E and the risk can be further exacerbated by eating raw seafood during travel. Besides, post-travel ESBL-E positive participants had increased abundances of several opportunistic pathogens such as Staphylococcus, Enterococcus, Escherichia/Shigella and Klebsiella. The random forest model integrating pre-travel microbiota and the identified travel-related risk factor could predict ESBL-E acquisition with an area under the curve of 75.4% (95% confidence interval: 57.9-93.0%).

CONCLUSIONS

In this study, we identified both travel-related risk factors and microbiota predictors for the risk of ESBL-E acquisition. Our results provide foundational knowledge for future developments of microbiota-based interventions to prevent ESBL-E acquisition during international travels.

Revisiting travellers' diarrhoea justifying antibiotic treatment: prospective study

BACKGROUND

As antimicrobials increase the risk of acquiring multidrug-resistant (MDR) bacteria, unnecessary antibiotics should be avoided for travellers' diarrhoea (TD). Antibiotics are recommended in TD accompanied by fever or incapacitation (TD justifying use of antibiotics, TDjuAB). Seeking tools for reducing antibiotic use, we explored factors predisposing to TDjuAB and scrutinized antibiotic treatment among those with TDjuAB [TDjuAB(+) subgroup] and those with diarrhoea not justifying antibiotics [TDjuAB(-) subgroup].

METHODS

We conducted a study among 370 prospectively recruited visitors to the tropics. Stool samples and questionnaires were collected before and after travel. Enteric pathogens were analysed by qPCR for enteropathogenic (EPEC), enteroaggregative (EAEC), enterotoxigenic (ETEC), enterohaemorrhagic (EHEC) and enteroinvasive (EIEC) E. coli/Shigella, Campylobacter, Salmonella, Yersinia and Vibrio cholerae, and for ETEC's toxins LT (heat-labile), STh (human heat-stable) and STp (porcine heat-stable). TD was defined by the WHO criteria and TDjuAB as diarrhoea accompanied by fever, and/or disrupting or preventing daily activities. Multivariable analysis was applied-separately for travel-related factors and pathogens-to identify risk factors for TDjuAB(+).

RESULTS

Among the 370 travellers, TD was contracted by 253 (68%), categorized as TDjuAB(+) in 93/253 (37%) and TDjuAB(-) in 160/253 (63%) of the cases. Antibiotics were used for TD by 41% in TDjuAB(+) and by 7% in the TDjuAB(-) group. Relative risk ratios (RRR)s are presented for both the TDjuAB(+) and the TDjuAB(-) groups. TDjuAB(+) was associated with long travel duration and young age. Among the 298 subjects not having taken antibiotics, increased RRRs were found e.g. for findings of Campylobacter coli/jejuni and ETEC's STh toxin.

CONCLUSIONS

The first to analyse risk factors for TDjuAB, our study presents RRRs for demographic and behavioural factors and for various pathogens. Only less than half of those in the TDjuAB(+) group took antibiotics, which demonstrates that most cases meeting the current criteria recover without antimicrobial treatment.

Less than you'd think-a prospective study on MRSA-colonization in healthy travellers

International travel has been identified as a major contributing factor to the global spread of MRSA. We examined the incidence of MRSA-colonization in a cohort of 196 travellers. We observed a low rate of only one case of MRSA, indicating a low risk of acquisition of MRSA-colonization in travel.

Dynamics of intestinal multidrug-resistant bacteria colonisation contracted by visitors to a high-endemic setting: a prospective, daily, real-time sampling study

BACKGROUND

Antimicrobial resistance is highly prevalent in low-income and middle-income countries. International travel contributes substantially to the global spread of intestinal multidrug-resistant Gram-negative bacteria. Hundreds of millions of annual visitors to low-income and middle-income countries are all exposed to intestinal multidrug-resistant Gram-negative bacteria resulting in 30-70% of them being colonised at their return. The colonisation process in high-exposure environments is poorly documented because data have only been derived from before travel and after travel sampling. We characterised colonisation dynamics by exploring daily stool samples while visiting a low-income and middle-income countries.

METHODS

In this prospective, daily, real-time sampling study 20 European visitors to Laos volunteered to provide daily stool samples and completed daily questionnaires for 22 days. Samples were initially assessed at Mahosot Hospital, Vientiane, Laos, for acquisition of extended-spectrum β-lactamase-producing (ESBL) Gram-negative bacteria followed by whole-genome sequencing of isolates at MicrobesNG, University of Birmingham, Birmingham, UK. The primary outcome of the study was to obtain data on the dynamics of intestinal multidrug-resistant bacteria acquisition.

FINDINGS

Between Sept 18 and Sept 20, 2015, 23 volunteers were recruited, of whom 20 (87%) European volunteers were included in the final study population. Although colonisation rates were 70% at the end of the study, daily sampling revealed that all participants had acquired ESBL-producing Gram-negative bacteria at some point during the study period; the colonisation status varied day by day. Whole-genome sequencing analysis ascribed the transient pattern of colonisation to sequential acquisition of new strains, resulting in a loss of detectable colonisation by the initial multidrug-resistant Gram-negative strains. 19 (95%) participants acquired two to seven strains. Of the 83 unique strains identified (53 Escherichia coli, 10 Klebsiella spp, and 20 other ESBL-producing Gram-negative bacteria), some were shared by as many as four (20%) participants.

INTERPRETATION

To our knowledge, this is the first study to characterise in real-time the dynamics of acquiring multidrug-resistant Gram-negative bacterial colonisation during travel. Our data show multiple transient colonisation events indicative of constant microbial competition and suggest that travellers are exposed to a greater burden of multidrug-resistant bacteria than previously thought. The data emphasise the need for preventing travellers' diarrhoea and limiting antibiotic use, addressing the two major factors predisposing colonisation.

FUNDING

The Finnish Governmental Subsidy for Health Science Research, The Scandinavian Society for Antimicrobial Chemotherapy, the Sigrid Jusélius Foundation, Biotechnology and Biological Sciences Research Council; Wellcome Trust, Medical Research Council; The Royal Society; Joint Programming Initiative on Antimicrobial Resistance, and European Research Council.

Acquisition of antimicrobial resistance determinants in Enterobacterales by international travelers from a large urban setting in Brazil

BACKGROUND

Antimicrobial resistance is increased by international mobility. We present data about intestinal colonization of travelers departing from a middle-income country.

METHODS

Travelers were recruited from 2015 to 2019, collected an anal stool specimen and answered a questionnaire before and after travel. Enterobacterales isolates were investigated for antimicrobial resistance; extended-spectrum beta-lactamase (ESBL) and carbapenemase production; plasmid-encoded cephalosporinases (pAmpC), plasmid-mediated quinolone resistance (PMQR) and mcr genes by PCR and sequencing; and association with travel related variables.

RESULTS

Among 210 travelers, 26 (12%) carried multidrug-resistant Enterobacterales (MDR-E) and 18 (9%) ESBL-producing Enterobacterales (ESBL-E) before travel, with an increased prevalence from 1% to 11% over the study years. Acquisition of MDR-E and ESBL-E occurred in 59 (32%) and 43 (22%) travelers, respectively, mostly bla_CTX-M-15 carrying Escherichia coli. One traveler acquired one isolate carrying bla_OXA-181 gene, and two others, isolates carrying mcr-1. PMQR were detected in 14 isolates of returning travelers. The risk of MDR-E acquisition was higher in Southeast Asia and the Indian subcontinent, and after using antimicrobial agents.

CONCLUSION

We describe an increasing pre-travel prevalence of ESBL-E colonization in subjects departing from this middle-income country over time. Travel to known risk areas and use of antimicrobial agents during travel were associated with acquisition of MDR-E. Travel advice is critical to mitigating this risk, as colonization by MDR-E may raise the chances of antimicrobial-resistant infections.

Colonization Dynamics of Multidrug-Resistant Klebsiella pneumoniae Are Dictated by Microbiota-Cluster Group Behavior over Individual Antibiotic Susceptibility: A Metataxonomic Analysis

Gastrointestinal carriage of multidrug-resistant (MDR) bacteria is one of the main risk factors for developing serious, difficult-to-treat infections. Given that there is currently no all-round solution to eliminate colonization with MDR bacteria, it is particularly important to understand the dynamic process of colonization to aid the development of novel decolonization strategies. The aim of our present study was to perform metataxonomic analyses of gut microbiota dynamics during colonization with an extended-spectrum β-lactamase (ESBL)- and carbapenemase-producing Klebsiella pneumoniae (ECKP) strain in mice; additionally, to ascertain the effects of antibiotic administration (ampicillin, ceftazidime, and ciprofloxacin) on the establishment and elimination of ECKP intestinal colonization. We have found that the phyla Bacteroidetes and Firmicutes were most dominant in all of the treatment groups; however, Bacteroidetes was more common in the groups treated with antibiotics compared to the control group. Significant differences were observed among the different antibiotic-treated groups in beta but not alpha diversity, implying that the difference is the relative abundance of some bacterial community members. Bacteria from the Lachnospiraceae family (including Agathobacter, Anaerostipes, Lachnoclostridium 11308, Lachnospiraceae UCG-004, Lachnospiraceae NK3A20 group 11318, Lachnospiraceae NK4A136 group 11319, Roseburia, and Tyzzerella) showed an inverse relationship with the carriage rate of the ECKP strain, whereas members of Enterobacteriaceae and the ECKP strain have shown a correlational relationship. Our results suggest that the composition of the microbial community plays a primary role in the MDR-colonization rate, whereas the antibiotic susceptibility of individual MDR strains affects this process to a lesser extent. Distinct bacterial families have associated into microbial clusters, collecting taxonomically close species to produce survival benefits in the gut. These associations do not develop at random, as they may be attributed to the presence of specific metabolomic networks. A new concept should be introduced in designing future endeavors for MDR decolonization, supplemented by knowledge of the composition of the host bacterial community and the identification of bacterial clusters capable of suppressing or enhancing the invader species.

Despite Predominance of Uropathogenic/Extraintestinal Pathotypes Among Travel-acquired Extended-spectrum β-Lactamase-producing Escherichia coli, the Most Commonly Associated Clinical Manifestation Is Travelers' Diarrhea

Background

One-third of the 100 million travelers to the tropics annually acquire extended-spectrum β-lactamase (ESBL)–producing Enterobacteriaceae (ESBL-PE), with undefined clinical consequences.

Methods

Symptoms suggesting Enterobacteriaceae infections were recorded prospectively among 430 Finnish travelers, 90 (21%) of whom acquired ESBL-PE abroad. ESBL-PE isolates underwent polymerase chain reaction–based detection of diarrheagenic Escherichia coli (DEC) pathotypes (enteroaggregative E. coli [EAEC], enteropathogenic E. coli [EPEC], enterotoxigenic E. coli [ETEC], enteroinvasive E. coli, and Shiga toxin–producing E. coli), and extraintestinal pathogenic/uropathogenic E. coli (ExPEC/UPEC). Laboratory-confirmed ESBL-PE infections were surveyed 5 years before and after travel.

Results

Among the 90 ESBL-PE carriers, manifestations of Enterobacteriaceae infection included travelers’ diarrhea (TD) (75/90 subjects) and urinary tract infection (UTI) (3/90). The carriers had 96 ESBL-producing E. coli isolates, 51% exhibiting a molecular pathotype: 13 (14%) were DEC (10 EAEC, 2 EPEC, 1 ETEC) (12 associated with TD) and 39 (41%) ExPEC/UPEC (none associated with UTI). Of ESBL-PE, 3 (3%) were ExPEC/UPEC-EAEC hybrids (2 associated with diarrhea, none with UTI). Potential ESBL-PE infections were detected in 15 of 90 subjects (17%). The 10-year medical record survey identified 4 laboratory-confirmed ESBL-PE infections among the 430 travelers, all in subjects who screened ESBL-PE negative after returning home from their index journeys but had traveled abroad before their infection episodes.

Conclusions

Half of all travel-acquired ESBL-producing E. coli strains qualified molecularly as pathogens. Extraintestinal and uropathogenic pathotypes outnumbered enteric pathotypes (41% vs 14%), yet the latter correlated more closely with symptomatic infection (0% vs 92%). Despite more ESBL-PE strains qualifying as ExPEC/UPEC than DEC, travel-acquired ESBL-PE are more often associated with TD than UTI.

Acquisition and Long-term Carriage of Multidrug-Resistant Organisms in US International Travelers

We performed prospective screening of stool for multidrug-resistant organisms from 608 US international travelers and identified an acquisition rate of 38% following travel. Carriage rates remained significantly elevated for at least 6 months post-travel. Travel-related diarrhea was a risk factor for acquisition, as well as for long-term carriage upon return.

Acquisition of multidrug-resistant bacteria and colistin resistance genes in French medical students on internships abroad

BACKGROUND

Acquisition of multidrug resistant bacteria (MDR) and colistin resistance genes by international travellers has been demonstrated. Studies conducted in medical students during internships abroad are scant.

METHODS

Nasopharyngeal, rectal, and vaginal swabs samples were collected from 382 French medical students before and after travel to investigate the acquisition of MDR bacteria. The bacterial diversity in the samples was assessed by culture on selective media. We also genetically characterised the isolates of MDR bacteria including Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E), methicillin-resistant Staphylococcus aureus (MRSA), and Carbapenemase-producing Enterobacteriacae (CPE) using the real-time polymerase chain reaction method. The samples were collected from 293 students and were investigated for mcr colistin-resistance genes using RT-PCR directly on the samples, followed by conventional PCR and sequencing.

RESULTS

A proportion of 29.3% (112/382) of the participants had acquired ESBL-E and 2.6% (10/382) had acquired CPE. The most common species and ESBL-E encoding gene were Escherichia coli (125/127 isolates, 98.4%) and bla_CTX-M-A (121/127, 95.3%), respectively. A proportion of 6.8% (20/293) of the participants had acquired mcr-1 genes, followed by mcr-3 (1/293, 0.3%) and mcr-8 (1/293, 0.3%). We found that taking part in humanitarian missions to orphanages (aRR = 2.01, p < 0.0001), being in contact with children during travel (aRR = 1.78, p = 0.006), the primary destination of travel being Vietnam (aRR = 2.15, p < 0.0001) and north India (aRR = 2.41, p = 0.001), using antibiotics during travel (aRR = 1.77, p = 0.01), and studying in 2018 (aRR = 1.55, p = 0.03) were associated with the acquisition of ESBL-E. When the primary destination of travel was Vietnam (aRR = 2.74, p < 0.0001) and the year of study was 2018 (aRR = 1.93, p < 0.002), this was associated with acquisition of colistin resistance genes.

CONCLUSION

Medical students are at a potential risk of acquiring ESBL-E, CPE and colistin resistance genes. A number of risk factors have been identified, which may be used to develop targeted preventive measures.

A Cross-Sectional Cohort Study of Extended-Spectrum-Beta-Lactamase-Producing Enterobacterales in Patients with Traveler's Diarrhea

Patients with traveler's diarrhea (TD) can acquire extended-spectrum-beta-lactamase (ESBL)-producing members of the Enterobacterales (EPE) during travel to areas of endemicity. The aim of the present study was to investigate the prevalence and characteristics of EPE carriage in travelers from southern Sweden who were sampled for bacterial diagnostics of TD compared to those of EPE carriage 10 years ago. Clinical samples sent for culture of common causes of bacterial enterocolitis, if the referral stated foreign travel, were included in the study. Antimicrobial susceptibility testing was done according to the EUCAST disk diffusion test method. EPE strains were subjected to whole-genome sequencing (WGS). Eighty-four of 303 patients carried a total of 92 ESBL-producing members of the Enterobacterales The overall prevalence of EPE in tested samples was thus 28%, compared to 24% 10 years earlier (P = 0.33). Among 86 strains available for WGS, 47 different sequence types (STs) were identified, and there were only 5 ST131 strains. Of the 79 Escherichia coli isolates, 76% carried at least one fim (type 1 fimbria) gene, 29% carried at least one pap (p-fimbriae) gene, and 43% were extraintestinal pathogenic E. coli (ExPEC) or uropathogenic E. coli (UPEC). Over half of the E. coli strains (57%) were intestinal pathogenic E. coli, most commonly enteroaggregative E. coli (EAEC) (33%), and enteroinvasive E. coli EIEC (22%). A relatively high proportion of patients with traveler's diarrhea carry EPE, but there was no significant increase compared to 10 years ago. Most E. coli strains were intestinal pathogenic strains. A comparatively high proportion of the strains were ExPEC/UPEC, many expressing the virulence genes pap and/or fim (This project was assigned ClinicalTrials.gov number NCT03866291.).

Clinical and drug resistance characteristics of Providencia stuartii infections in 76 patients

OBJECTIVES

To investigate the clinical and drug resistance characteristics of Providencia stuartii infections in the Huainan region of Anhui and provide a reference for the clinical selection of antimicrobial agents.

METHODS

This single-center retrospective analysis included 76 patients with P. stuartii infection in Huainan during the period from October 2018 to March 2020. The hospital department in which the patients were treated and the drug susceptibility characteristics of the P. stuartii isolates were recorded.

RESULTS

Among the 76 patients, the lung was the most common site of infection, and intensive care unit was the main hospital department. Extended spectrum beta-lactamase screening revealed expression by all 76 isolates of P. stuartii. Of the 76 isolates, 92.1% exhibited multiple drug resistance or extensive drug resistance. P. stuartii isolates were sensitive to cefepime and imipenem, but not to other beta-lactam antibiotics. Twenty isolates were resistant to all 21 types of antibiotics. Of the 20 patients infected with extensively drug-resistant isolates, nine (45%) died.

CONCLUSIONS

Drug resistance is increasing in P. stuartii. The antimicrobial agent imipenem may be effective for treatment of P. stuartii infections. Fluoroquinolones, aminoglycosides, and fourth-generation cephalosporins are suitable options for antibiotic therapy.

Global travel and Gram-negative bacterial resistance; implications on clinical management

INTRODUCTION

Antimicrobial resistance (AR) is escalating worldwide with the potential for dire consequences, global travel contributes to the dissemination of resistant pathogens from one region to another. The World Health Organization identified the rapid emergence and prevalence of carbapenem-resistant Gram-negative species, including Enterobacterales, Acinetobacter baumannii, and Pseudomonas aeruginosa, as an international crisis due to treatment challenges, poor health outcomes, increased mortality, and high economic costs caused by these pathogens.

AREAS COVERED

This review describes key carbapenem-resistant (CR) Gram-negative species, changes in current global and regional trends, AR surveillance and reporting, and identifies drivers of change, specifically travel. Finally, we review clinical implications and challenges of treating CR infections which exist due to widespread dissemination of CR bacteria. A literature search was conducted using PubMed, Google Scholar, Ebsco, and ProQuest (from 2000 to December 2019).

EXPERT OPINION

The level of global travel is increasing, and antimicrobial resistance continues to disseminate worldwide. Healthcare providers risk assessment for AR needs to consider a patient's recent travel history, including pre-travel and intra-travel antimicrobial prescription, and potential exposure based on geography. Patient education, healthcare provider awareness, and access to data and surveillance resources are critical to inform antimicrobial selection and improve health outcomes.

Characteristics of Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae and Contact to Animals in Estonia

We have attempted to define the prevalence and risk factors of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-Enterobacteriaceae) carriage, and to characterize antimicrobial susceptibility, beta-lactamase genes, and major types of isolated strains in volunteers, with a specific focus on humans in contact with animals. Samples were collected from 207 volunteers (veterinarians, pig farmers, dog owners, etc.) and cultured on selective agar. Clonal relationships of the isolated ESBL-Enterobacteriaceae were determined by whole genome sequencing and multi-locus sequence typing. Beta-lactamases were detected using a homology search. Subjects filled in questionnaires analyzed by univariate and multiple logistic regression. Colonization with ESBL-Enterobacteriaceae was found in fecal samples of 14 individuals (6.8%; 95%CI: 3.75–11.09%). In multiple regression analysis, working as a pig farmer was a significant risk factor for ESBL-Enterobacteriaceae carriage (OR 4.8; 95%CI 1.2–19.1). The only species isolated was Escherichia coli that distributed into 11 sequence types. All ESBL-Enterobacteriaceae isolates were of CTX-M genotype, with the blaCTX-M-1 being the most prevalent and more common in pig farmers than in other groups. Despite the generally low prevalence of ESBL-Enterobacteriaceae in Estonia, the pig farmers may still pose a threat to transfer resistant microorganisms. The clinical relevance of predominant blaCTX-M-1 carrying E. coli is still unclear and needs further studies.

CON: COVID-19 will not result in increased antimicrobial resistance prevalence

Antimicrobial resistance (AMR) is affected by many factors, but too much of our focus has been on antimicrobial usage. The major factor that drives resistance rates globally is spread. The COVID-19 pandemic should lead to improved infection prevention and control practices, both in healthcare facilities and the community. COVID-19 will also have ongoing and profound effects on local, national and international travel. All these factors should lead to a decrease in the spread of resistant bacteria. So overall, COVID-19 should lead to a fall in resistance rates seen in many countries. For this debate we show why, overall, COVID-19 will not result in increased AMR prevalence. But globally, changes in AMR rates will not be uniform. In wealthier and developed countries, resistance rates will likely decrease, but in many other countries there are already too many factors associated with poor controls on the spread of bacteria and viruses (e.g. poor water and sanitation, poor public health, corrupt government, inadequate housing, etc.). In these countries, if economies and governance deteriorate further, we might see even more transmission of resistant bacteria.