Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Preliminary investigations on a simple polyelectrolyte derived from (CH 2 CH 2 C(COOH) 2 ) n : Unexpected solubility-insolubility pattern controlled selectively by the nature of the alkali counterion

International audienceMonodisperse samples of alkali poly(trimethylene-1,1-dicarboxylate) polyelectrolytes of (CH2CH2C(COO(-))2)n structure and of low to moderate molecular weights have been synthesized and characterized. These polymers are densely and evenly decorated by carboxylate groups, with the anionic moieties extending symmetrically in transverse directions on every third carbon alongside the backbone. In sharp contrast to other polyelectrolytes, they easily precipitate with sodium and potassium ions in water. The precipitation is selective, the solubility varying with the nature of the alkali cation in the order: Li+ > K+ > Na+. Precipitation is fast and reversible, the solubility-insolubility transition being rapidly crossed in both directions when the proper alkali ion is added in excess to the solution/sus- pension. Experimental investigations (WAXS, FTIR) on the precipitated polymer and DFT theoretical calculations on model 1:1 complexes of malonate subunits with alkali cations have been carried out in order to cast some light on the above phenomena. In addition, a model molecule (CH3C(COOH)2CH2CH2C(COOH)2CH3) has been prepared, supporting the structure of the obtained polyelectrolyte as well as the formation of specific structures at half-deprotonation of the poly(carboxylic acid)

Highly luminescent PANI-Si nanoparticle capsules using miniemulsion

We used miniemulsion to synthesize novel water-soluble dispersion of nanocapsules with a polyaniline (PANI) shell and luminescent ultrasmall Si nanoparticle core with diameters of 50–300 nm. The capsules are functionalized with aromatic sulfonic acid. The capsules may be reconstituted in thin films or structured surfaces. The stability of the luminescence and dispersion of the capsules is studied under a wide range of pH conditions. The multiplicity of nanoparticles in the core provides highly amplified and reproducible signal for luminescence-based imaging using standard fluorescence microscopy, while the PANI shell allows a variety of routes for functionalization as well as electrical interrogation, which enables a wide range of biosensing/imaging applications

Soluble silicon nanoparticles–polyaniline capsules for biosensing and imaging

We used miniemulsion to synthesize novel water-soluble dispersion of nanocapsules with a polyaniline (PANI) shell and luminescent ultrasmall Si nanoparticle core with diameters of 50–300 nm. The capsules are functionalized with aromatic sulfonic acid. The capsules may be reconstituted in thin films or structured surfaces. The stability of the luminescence and dispersion of the capsules is studied under a wide range of pH conditions. The multiplicity of nanoparticles in the core provides highly amplified and reproducible signal for luminescence-based imaging using standard fluorescence microscopy, while the PANI shell allows a variety of routes for functionalization as well as electrical interrogation, which enables a wide range of biosensing/imaging applications

Highly luminescent PANI-Si nanoparticle capsules using miniemulsion

We used miniemulsion to synthesize novel water-soluble dispersion of nanocapsules with a polyaniline (PANI) shell and luminescent ultrasmall Si nanoparticle core with diameters of 50–300 nm. The capsules are functionalized with aromatic sulfonic acid. The capsules may be reconstituted in thin films or structured surfaces. The stability of the luminescence and dispersion of the capsules is studied under a wide range of pH conditions. The multiplicity of nanoparticles in the core provides highly amplified and reproducible signal for luminescence-based imaging using standard fluorescence microscopy, while the PANI shell allows a variety of routes for functionalization as well as electrical interrogation, which enables a wide range of biosensing/imaging applications

Polyaniline–Si Nanoparticle Nanocapsules as a Dual Photovoltaic Sensitizer

We examine the optical and structural properties of polyaniline–silicon nanoparticle capsules — a novel organic/inorganic material. The Si particles absorb UV/blue efficiently and green moderately, while polyaniline (PANI) in its green emeraldine state absorbs UV and red/IR efficiently, effectively providing absorption over a wide range of the solar spectrum. The capsules are produced by miniemulsion of aniline monomers in the presence of Si nanoparticles. Thin films of the capsules were formed on a variety of substrates. We use high resolution transmission electron microscopy (HTEM) and scanning electron microscopy (SEM) to record the structural properties. We also monitor the optical properties of the Si core and the PANI shell using fluorescence microscopy under UV and visible irradiation. Upon on-off cycles of UV irradiation and visible light, the red core switches reversibly between bright and dark states while PANI switches reversibly between emeraldine green and pernigraniline violet states. The results are analyzed in terms of excitonic excitation, charge separation, and transport between the core and the shell, which is useful for photovoltaic applications

Polyaniline–Si Nanoparticle Nanocapsules as a Dual Photovoltaic Sensitizer

We examine the optical and structural properties of polyaniline–silicon nanoparticle capsules — a novel organic/inorganic material. The Si particles absorb UV/blue efficiently and green moderately, while polyaniline (PANI) in its green emeraldine state absorbs UV and red/IR efficiently, effectively providing absorption over a wide range of the solar spectrum. The capsules are produced by miniemulsion of aniline monomers in the presence of Si nanoparticles. Thin films of the capsules were formed on a variety of substrates. We use high resolution transmission electron microscopy (HTEM) and scanning electron microscopy (SEM) to record the structural properties. We also monitor the optical properties of the Si core and the PANI shell using fluorescence microscopy under UV and visible irradiation. Upon on-off cycles of UV irradiation and visible light, the red core switches reversibly between bright and dark states while PANI switches reversibly between emeraldine green and pernigraniline violet states. The results are analyzed in terms of excitonic excitation, charge separation, and transport between the core and the shell, which is useful for photovoltaic applications

Polyaniline–Si Nanoparticle Nanocapsules as a Dual Photovoltaic Sensitizer

We examine the optical and structural properties of polyaniline–silicon nanoparticle capsules — a novel organic/inorganic material. The Si particles absorb UV/blue efficiently and green moderately, while polyaniline (PANI) in its green emeraldine state absorbs UV and red/IR efficiently, effectively providing absorption over a wide range of the solar spectrum. The capsules are produced by miniemulsion of aniline monomers in the presence of Si nanoparticles. Thin films of the capsules were formed on a variety of substrates. We use high resolution transmission electron microscopy (HTEM) and scanning electron microscopy (SEM) to record the structural properties. We also monitor the optical properties of the Si core and the PANI shell using fluorescence microscopy under UV and visible irradiation. Upon on-off cycles of UV irradiation and visible light, the red core switches reversibly between bright and dark states while PANI switches reversibly between emeraldine green and pernigraniline violet states. The results are analyzed in terms of excitonic excitation, charge separation, and transport between the core and the shell, which is useful for photovoltaic applications

Wideband luminescence from bandgap-matched Mg-based Si core-shell geometry nanocomposite

We use wet treatment to integrate red-luminescent Si nanoparticles with Mg-based wide-bandgap insulators Mg(OH) and MgO (5.7 and 7.3 eV respectively). In the process, Mg2+ is reduced on Si nanoparticle clusters, while suffering combustion in water, producing a spatially inhomogeneous Mg(OH)2/MgO-Si nanoparticle composite with an inner material predominantly made of Si, and a coating consisting predominantly of magnesium and oxygen (“core-shell” geometry). The nanocomposite exhibit luminescence covering nearly entire visible range. Results are consistent with formation of Mg(OH)2/MgO phase with direct 3.43-eV bandgap matching that of Si, with in-gap blue-green emitting states of charged Mg and O vacancies. Bandgap match with nanocomposite architecture affords strong enough coupling for the materials to nearly act as a single hybrid material with novel luminescence for photonic and photovoltaic applications