The antibiotic resistome and microbiota landscape of refugees from Syria, Iraq and Afghanistan in Germany

Nutritional status reshapes gut microbiota composition in adolescent Afghan refugees in Peshawar, Pakistan

Although the human gut microbiome, and its role in health and disease, have been extensively studied in different populations, a comprehensive assessment of gut microbiome composition has not been performed in vulnerable refugee populations. In this study, we hypothesized that overall nutritional status, as indicated by serum micronutrients concentrations, is an important driver of variations in gut microbiome composition. Therefore, gut-microbiome diversity and associated demographic, health and nutritional factors were assessed in adolescent Afghan refugees (n=206). Blood and faecal samples were collected and analysed for nutrition status markers and 16S rRNA gene amplicon-based community profiling, respectively. Bioinformatics and statistical analysis were performed using SPSS, QIIME and R. Overall, 56 distinct phyla, 117 families and 252 genera were identified in the faecal samples. Bacterial diversity (alpha and beta diversity) and the Firmicutes:Bacteroidetes (F/B) ratio were significantly higher in the 15 to 19 year old age group (cf. the 10-14 age group) but were lower in the underweight and vitamin D deficient groups. Furthermore, LEfSe analysis identified significant differences in the relative abundance of bacterial genera based on age, BMI and micronutrient (vitamins and minerals) status. These results were further scrutinised by correlation analysis which confirmed that age, BMI and micronutrient status show significant correlations with F/B ratio and the relative abundance of specific bacterial taxa. Collectively, our study provides the first indication of how the gut-microbiota profile of adolescent Afghan refugees is associated with a range of nutrition-status factors. These findings can thus provide a basis for translational microbiota research aimed at improving the health of such understudied and vulnerable populations.

Antimicrobial resistance among refugees and asylum seekers: a global systematic review and meta-analysis

Refugees and asylum seekers might have an increased risk of antimicrobial resistance (AMR) carriage or infection due to several factors, with conflict and war known to accelerate the spread of AMR. However, data are scarce on prevalence and risk factors for AMR among refugees and asylum seekers and how they are affected globally; in addition, how their risk compares to that of the host-country population is unclear. We aimed to explore and assess global AMR data among refugees and asylum seekers. Ovid (MEDLINE and Embase) and PubMed were searched for peer-reviewed primary research articles from Jan 1, 2015, to Oct 23, 2023, and articles were included if they reported carriage or infection with laboratory-confirmed drug-resistant organisms in refugees or asylum seekers from any country. Of 884 articles identified, 41 reported prevalence of AMR among 16 970 refugees and asylum seekers and were included in the study. The most common phenotypes reported were multidrug-resistant Gram-negative bacteria (n=26; prevalence ranged from 4·2% to 60·8%), methicillin-resistant Staphylococcus aureus (n=24; 0·92% to 73%), and extended-spectrum β-lactamase-producing Gram-negative bacteria (n=20; 1·6% to 61·1%). Refugees and asylum seekers had a higher likelihood of carriage or infection with any AMR than the host-country population (n=7849 vs n=81 283, respectively; odds ratio 2·88, 95% CI 2·61-3·18; I2=94%). Refugees and asylum seekers are at an increased risk of AMR carriage and infection, with our data suggesting that refugees and asylum seekers might be exposed to conditions that support the emergence of drug resistance (including living in overcrowded camps and facing barriers to health and vaccine systems). Hence, more global and regional data on AMR are needed through strengthened surveillance programmes and health-care facilities, especially in low-income and middle-income countries. Increased efforts are needed to drive improvements in infection prevention and control (including vaccination), antimicrobial stewardship, treatment strategies tailored to groups at high risk, accessiblity to quality health care in these populations at risk globally, and address risk factors such as poor living and transit conditions.

Gut microbiota composition in patients with Crohn's disease in Saudi Arabia

Crohn's disease (CD) entails intricate interactions with gut microbiome diversity, richness, and composition. The relationship between CD and gut microbiome is not clearly understood and has not been previously characterized in Saudi Arabia. We performed statistical analysis about various factors influencing CD activity and microbiota dysbiosis, including diagnosis, treatment, and its impact on their quality of life as well as high-throughput metagenomic V3-V4 16S rRNA encoding gene hypervariable region of a total of eighty patients with CD, both in its active and inactive state with healthy controls. The results were correlated with the demographic and lifestyle information, which the participants provided via a questionnaire. α-diversity measures indicated lower bacterial diversity and richness in the active and inactive CD groups compared to the control group. Greater dysbiosis was observed in the active CD patients compared to the inactive form of the disease, showed by a reduction in microbial diversity. Specific pathogenic bacteria such as Filifactor, Peptoniphilus, and Sellimonas were identified as characteristic of CD groups. In contrast, anti-inflammatory bacteria like Defluviitalea, Papillibacter, and Petroclostridium were associated with the control group. Among the various factors influencing disease activity and microbiota dysbiosis, smoking emerged as the most significant, with reduced α-diversity and richness for the smokers in all groups, and proinflammatory Fusobacteria was more present (p<0.05). Opposite to the control group, microbial diversity and richness were lower in CD participants of older age compared to younger ones, and male CD participants showed less diversity compared to women participants from the same groups. Our results describe the first report on the relationship between microbiota and Crohn's disease progress in Saudi Arabia, which may provide a theoretical basis for the application of therapeutic methods to regulate gut microbes in CD.

Impact of wars and natural disasters on emerging and re-emerging infectious diseases

Emerging Infectious Diseases (EIDs) and Re-Emerging Infectious Diseases (REIDs) constitute significant health problems and are becoming of major importance. Up to 75% of EIDs and REIDs have zoonotic origin. Several factors such as the destruction of natural habitats leading humans and animals to live in close proximity, ecological changes due to natural disasters, population migration resulting from war or conflict, interruption or decrease in disease prevention programs, and insufficient vector control applications and sanitation are involved in disease emergence and distribution. War and natural disasters have a great impact on the emergence/re-emergence of diseases in the population. According to a World Bank estimation, two billion people are living in poverty and fragility situations. Wars destroy health systems and infrastructure, curtail existing disease control programs, and cause population movement leading to an increase in exposure to health risks and favor the emergence of infectious diseases. A total of 432 catastrophic cases associated with natural disasters were recorded globally in 2021. Natural disasters increase the risk of EID and REID outbreaks by damaging infrastructure and leading to displacement of populations. A Generic National Action Plan covering risk assessment, mechanism for action, determination of roles and responsibilities of each sector, the establishment of a coordination mechanism, etc. should be developed.

The need to increase antimicrobial resistance surveillance among forcibly displaced persons (FDPs)

Antimicrobial resistance (AMR) poses a significant threat to human health as 4.95 million deaths were associated with bacterial AMR in 2019 and is projected to reach 10 million by 2050. To mitigate AMR, surveillance is an essential tool for determining the burden of AMR and providing the necessary information for its control. However, the global AMR surveillance is inadequate and particularly limited among forcibly displaced persons (FDPs) despite having higher risks of harboring these pathogens. Predisposing factors among this group include poor living conditions, limited access to treatment and diagnostic tests, and inadequate trained health professionals in refugee camps. Strengthening AMR surveillance among FDPs would address the identified gaps and facilitate formulation and implementation of evidence-based policies on AMR control and prevention response. This article provides information on the growing population of FDPs, factors contributing to the AMR burden and AMR surveillance gaps in FDPs and highlighted recommendations for control.

Health condition of Afghan refugees residing in Iran in comparison to Germany: a systematic review of empirical studies

BACKGROUND

The re-emerging dominance of the Taliban in Afghanistan in 2021 caused a new wave of Afghan refugees heading Iran and neighboring countries. Iran in the Middle East and Germany in Europe are two major host countries to the largest populations of Afghan refugees. In both countries, several studies have been done to assess the health condition of refugees.

OBJECTIVES

To systematically review the existing literature to identify similarities and differences of health conditions of Afghan refugees living in the two countries, and to synthesize evidence on the health status and health care access of these populations.

METHODS

Related electronic databases and grey literature of Iran and Germany on the health of Afghan refugees were scanned and searched up for the period 2000-2020. Key terms were formed by combining "Afghan refugees or immigrants or populations or asylum seekers", "Physical or mental health", "Healthcare service or access or use", "Iran or Germany". Empirical studies were considered if they contained samples of Afghan refugees with particular outcomes for Afghans. Results were categorized for both countries in the three main areas of physical health, mental health, and access/use of healthcare services.

RESULTS

Nine hundred twenty-two documents were extracted, of which 75 full-texts were finally reviewed. 60 documents belonged to the health condition of Afghan refugees residing in Iran including 43 in physical health, 6 in mental health, 8 in healthcare access and use, and 3 in multiple aspects of health, and 15 belonged to Germany including 7 in physical health, 4 in mental health, 2 in healthcare access and use, and 2 in multiple aspects of health. A less explicit evaluation of the overall health condition of Afghan refugees was observable, particularly for Germany. While matches on the study subject exist for both countries, in comparison to Germany, we extracted more quantitative and qualitative health studies on Afghan refugees of the mentioned areas from Iran. German health studies were rare, less qualitative, and more on the health condition of diverse refugee groups in general.

CONCLUSIONS

Wide gaps and unanswered questions related to mental health and overall health status of the Afghan refugee population are observable, especially in Germany. Our systematic review identified the gap in evidence, which we would recommend to bridge using a wider lens to comprehensively assess the overall condition of refugees considering associations between health and socio-economic and cultural determinants instead of a one-dimensional approach. Further, within health studies on refugee populations, we recommend stratification of results by the country of origin to capture the within-group diversity among refugees with different countries of origin.

Catch-22: War, Refugees, COVID-19, and the Scourge of Antimicrobial Resistance

Wars have hidden repercussions beyond the immediate losses of life, well-being, and prosperity. Those that flee wars and seek refuge in safer locations are not immune to the tragic impacts. Of particular concern is the susceptibility of the refugee populations to infectious diseases and antimicrobial-resistant pathogens. This poses a detrimental risk to these disenfranchised populations, who often have limited access to medical care, sanitation, and nutritious and safe food. Furthermore, antimicrobial-resistant pathogens in refugees can be both transmitted to and acquired from their hosting communities. The latter is particularly problematic when the host countries suffer from serious challenges such as limited resources, pollution, and widespread antimicrobial resistance (AMR). Here, we discuss AMR in refugees of the ongoing Syrian war, a conflict that resulted in the largest population displacement in recent history. We argue that Syrian refugees and their hosting communities are at an elevated risk of complicated and life-threatening AMR infections. We also call on the international community to address this grievous problem that threatens the disenfranchised refugee populations and can spill over across geographic borders to affect multiple countries.

Stressor-Specific Microbiota Intervention

To date, mental disorders are diagnosed and treated by the subjective judgment of psychiatrists based on diagnostic criteria and treatment guidelines, respectively. Mental disorders are heterogeneous illnesses with a substantial treatment-refractory rate. Thus, there is a great need for novel treatment approaches. This article proposes a treatment approach centered on the concept of the gut–brain axis. There is mounting evidence indicating an association between stressors, microbiota, microglia, and mental disorders. Stressors might facilitate dysbiosis, inflammation, and the occurrence of mental disorders. This novel treatment approach is based on the idea that stressor types instead of the heterogeneous psychiatric diagnosis might be closer to the neurobiological underpinnings of mental disorders. First of all, patients with treatment-resistant mental disorders will be asked to describe their major stressors. Then, clinicians will calculate the total threat score and the total deprivation score. Subsequently, treatment tailored to the major stressor type will be administered to restore a healthy gut microbiome. Presumably, treatment will be aimed at increasing microbiota diversity in those who mainly have deprivation stressors and boosting Actinobacteria in those who have mainly threat stressors. Large-scale clinical trials are warranted to test this hypothetical approach.

Antimicrobial resistance in the protracted Syrian conflict: halting a war in the war

The Syrian conflict has damaged key infrastructure and indirectly affected almost all parts of the Middle East and Europe, with no end in sight. Exhausting conditions created by the Syrian crisis and related massive displacement promote the emergence of numerous public health problems that fuel antimicrobial resistance (AMR) development. Here, we explore the current situation of the Syrian displaced population, and AMR inside Syria and among refugees in host countries. We then suggest a roadmap of selected key interventions and strategies to address the threat of AMR in the context of the Syrian crisis. These recommendations are intended to urge health policy-makers in governments and international health organizations to optimize and push for implementing an effective policy taking into consideration the current obstacles.

Predominance of CTX-M-15-producing ST131 strains among ESBL-producing Escherichia coli isolated from asylum seekers in the Netherlands

Objectives

Numerous studies show increased prevalence of MDR bacteria amongst asylum seekers, but data on the molecular profiles of such strains are limited. We aimed to evaluate the molecular profiles of ESBL-producing Escherichia coli (ESBL-E. coli) strains isolated from asylum seekers and investigate their phylogenetic relatedness.

Methods

WGS data of ESBL-E. coli isolates from asylum seekers, retrieved from 1 January to 31 December 2016, were analysed to assess MLST STs, fim types, phylogroups and resistance genes. Fifty-two ESBL-E. coli isolates from the Dutch–German border region were used for genome comparison purposes as a control group.

Results

Among 112 ESBL-E. coli isolates from asylum seekers, originating mostly from Syria (n = 40) and Iraq (n = 15), the majority belonged to ST131 (21.4%) and ST10 (17.0%). The predominant gene for β-lactam resistance was bla_CTX-M-15 (67.9%), followed by the often co-detected bla_TEM-1B (39.3%). No mcr or carbapenemase genes were detected. The majority of the strains belonged to phylogroups B2 (38.4%) and A (32.1%), carrying fimH27 (25%) and fimH30 (19.6%). A core genome MLST minimum spanning tree did not reveal clusters containing strains from the asylum seekers and the control group. Five clusters were formed within the asylum seeker group, by strains isolated from people originating from different countries.

Conclusions

The most frequently isolated clones in this study were isolated on a regular basis within the Dutch population before the increase in the asylum seeker population. No mcr- or carbapenemase-producing clones were detected among the asylum seeker population. Minor clustering was observed amongst the asylum seeker strains.

Macleaya cordata extract, an antibiotic alternative, does not contribute to antibiotic resistance gene dissemination

The abuse of antibiotics and their associated health risks are receiving global attention. The use of antibiotic additives in fodder has been banned in the European Union since 2006 and in China since 2020. Antibiotic alternatives are being developed, but their risks to the soil ecosystem remain poorly understood. Here, we compared the effects of the antibiotic oxytetracycline (OTC10, 10 mg/kg) with those of a Macleaya cordata extract (MCE, 10 and 100 mg/kg), the major antibiotic substitute. All tested concentrations of MCE and OTC10 exerted slight effects on the soil microbiome, but OTC10 and MCE100 could interfere with the structures and functions of the gut microbiome and might thus affect the soil ecological functions of Enchytraeus crypticus. Furthermore, OTC10 exposure inevitably increased the antibiotic resistance gene (ARG) abundance by 213%, whereas MCE did not induce ARG dissemination, which explains why MCE is considered to be associated with a low ecological risk. Our research provides the first demonstration of the risks posed by antibiotic alternatives to soil animals from the perspective of environmental toxicology and explores the potential development of antibiotic alternatives associated with a low ecological risk from a new perspective.

Systematic review of human gut resistome studies revealed variable definitions and approaches

In this review, we highlight the variations of gut resistome studies, which may preclude comparisons and translational interpretations. Of 22 included studies, a range of 12 to 2000 antibiotic resistance (AR) genes were profiled. Overall, studies defined a healthy gut resistome as subjects who had not taken antibiotics in the last three to 12 months prior to sampling. In studies with de novo assembly, AR genes were identified based on variable nucleotide or amino acid sequence similarities. Different marker genes were used for defining resistance to a given antibiotic class. Validation of phenotypic resistance in the laboratory is frequently lacking. Cryptic resistance, collateral sensitivity and the interaction with repressors or promotors were not investigated. International consensus is needed for selecting marker genes to define resistance to a given antibiotic class in addition to uniformity in phenotypic validation and bioinformatics pipelines.

NOD2 Influences Trajectories of Intestinal Microbiota Recovery After Antibiotic Perturbation

BACKGROUND & AIMS

Loss-of-function variants in nucleotide-binding oligomerization domain-containing protein 2 (NOD2) impair the recognition of the bacterial cell wall component muramyl-dipeptide and are associated with an increased risk for developing Crohn's disease. Likewise, exposure to antibiotics increases the individual risk for developing inflammatory bowel disease. Here, we studied the long-term impact of NOD2 on the ability of the gut bacterial and fungal microbiota to recover after antibiotic treatment.

METHODS

Two cohorts of 20-week-old and 52-week-old wild-type (WT) C57BL/6J and NOD2 knockout (Nod2-KO) mice were treated with broad-spectrum antibiotics and fecal samples were collected to investigate temporal dynamics of the intestinal microbiota (bacteria and fungi) using 16S ribosomal RNA and internal transcribed spacer 1 sequencing. In addition, 2 sets of germ-free WT mice were colonized with either WT or Nod2-KO after antibiotic donor microbiota and the severity of intestinal inflammation was monitored in the colonized mice.

RESULTS

Antibiotic exposure caused long-term shifts in the bacterial and fungal community composition. Genetic ablation of NOD2 was associated with delayed body weight gain after antibiotic treatment and an impaired recovery of the bacterial gut microbiota. Transfer of the postantibiotic fecal microbiota of Nod2-KO mice induced an intestinal inflammatory response in the colons of germ-free recipient mice compared with respective microbiota from WT controls based on histopathology and gene expression analyses.

CONCLUSIONS

Our data show that the bacterial sensor NOD2 contributes to intestinal microbial community composition after antibiotic treatment and may add to the explanation of how defects in the NOD2 signaling pathway are involved in the etiology of Crohn's disease.

THE EXPOSOME IN HUMAN EVOLUTION: FROM DUST TO DIESEL

Global exposures to air pollution and cigarette smoke are novel in human evolutionary history and are associated with about 16 million premature deaths per year. We investigate the history of the human exposome for relationships between novel environmental toxins and genetic changes during human evolution in six phases. Phase I: With increased walking on savannas, early human ancestors inhaled crustal dust, fecal aerosols, and spores; carrion scavenging introduced new infectious pathogens. Phase II: Domestic fire exposed early Homo to novel toxins from smoke and cooking. Phases III and IV: Neolithic to preindustrial Homo sapiens incurred infectious pathogens from domestic animals and dense communities with limited sanitation. Phase V: Industrialization introduced novel toxins from fossil fuels, industrial chemicals, and tobacco at the same time infectious pathogens were diminishing. Thereby, pathogen-driven causes of mortality were replaced by chronic diseases driven by sterile inflammogens, exogenous and endogenous. Phase VI: Considers future health during global warming with increased air pollution and infections. We hypothesize that adaptation to some ancient toxins persists in genetic variations associated with inflammation and longevity.

Trophic Transfer of Antibiotic Resistance Genes in a Soil Detritus Food Chain

The presence and spread of antibiotic resistance genes (ARGs) are causing substantial global public concern; however, the dispersal of ARGs in the food chain is poorly understood. Here, we experimented with a soil collembolan ( Folsomia candida)-predatory mite ( Hypoaspis aculeifer) model food chain to study trophic transfer of ARGs in a manure-contaminated soil ecosystem. Our results showed that manure amendment of soil could significantly increase ARGs in the soil collembolan microbiome. With the ARGs in the prey collembolan microbiome increasing, an increase in ARGs in the predatory mite microbiome was also observed, especially for three high abundant ARGs ( blaSHV, fosX and aph6ia). Three unique ARGs were transferred into the microbiome of the predatory mite from manure amended soil via the prey collembolan ( aac(6' )-lb(akaaacA4), yidY_mdtL and tolC). Manure amendment altered the composition and structure and reduced the diversity of the microbiomes of the prey collembolan and the predatory mite. We further reveal that bacterial communities and mobile genetic elements were two important drivers for the trophic transfer of ARGs, not just for ARGs distribution in the samples. These findings suggest that the importance of food chain transmission of ARGs for the dispersal of resistance genes in soil ecosystems may be underestimated.

The unique composition of Indian gut microbiome, gene catalogue, and associated fecal metabolome deciphered using multi-omics approaches

BACKGROUND

Metagenomic studies carried out in the past decade have led to an enhanced understanding of the gut microbiome in human health; however, the Indian gut microbiome has not been well explored. We analyzed the gut microbiome of 110 healthy individuals from two distinct locations (North-Central and Southern) in India using multi-omics approaches, including 16S rRNA gene amplicon sequencing, whole-genome shotgun metagenomic sequencing, and metabolomic profiling of fecal and serum samples.

RESULTS

The gene catalogue established in this study emphasizes the uniqueness of the Indian gut microbiome in comparison to other populations. The gut microbiome of the cohort from North-Central India, which was primarily consuming a plant-based diet, was found to be associated with Prevotella and also showed an enrichment of branched chain amino acid (BCAA) and lipopolysaccharide biosynthesis pathways. In contrast, the gut microbiome of the cohort from Southern India, which was consuming an omnivorous diet, showed associations with Bacteroides, Ruminococcus, and Faecalibacterium and had an enrichment of short chain fatty acid biosynthesis pathway and BCAA transporters. This corroborated well with the metabolomics results, which showed higher concentration of BCAAs in the serum metabolome of the North-Central cohort and an association with Prevotella. In contrast, the concentration of BCAAs was found to be higher in the fecal metabolome of the Southern-India cohort and showed a positive correlation with the higher abundance of BCAA transporters.

CONCLUSIONS

The study reveals the unique composition of the Indian gut microbiome, establishes the Indian gut microbial gene catalogue, and compares it with the gut microbiome of other populations. The functional associations revealed using metagenomic and metabolomic approaches provide novel insights on the gut-microbe-metabolic axis, which will be useful for future epidemiological and translational researches.

Metagenomics and Faecal Metabolomics Integrative Analysis towards the Impaired Glucose Regulation and Type 2 Diabetes in Uyghur-Related Omics

OBJECTIVE

Gut microbiota and their metabolites play an important role in the development of type 2 diabetes mellitus (T2DM). This research was designed to study the relationship between gut microbiota and faecal metabolites of Uyghur newly onset T2DM and impaired glucose regulation (IGR) patients.

MATERIALS AND METHODS

A total of 60 different glycemic Uyghur subjects were enrolled and divided into T2DM, IGR, and normal glucose tolerance (NGT) groups. Metagenomics and LC-MS-based untargeted faecal metabolomics were employed. Correlations between bacterial composition and faecal metabolomics were evaluated.

RESULTS

We discovered that the composition and diversity of gut microbiota in newly onset T2DM and IGR were different from those in NGT. The α-diversity was higher in NGT than in T2DM and IGR; β-diversity analysis revealed apparent differences in the bacterial community structures between patients with T2DM, IGR, and NGT. LC-MS faecal metabolomics analysis discovered different metabolomics features in the three groups. Alchornoic acid, PE (14 : 0/20 : 3), PI, L-tyrosine, LysoPC (15 : 0), protorifamycin I, pimelic acid, epothilone A, 7-dehydro-desmosterol, L-lysine, LysoPC (14 : 1), and teasterone are the most significant differential enriched metabolites. Most of the differential enriched metabolites were involved in metabolic processes, including carbohydrate metabolism, starch and sucrose metabolism, phenylpropanoid biosynthesis, and biosynthesis of amino acids. Procrustes analysis and correlation analysis identified correlations between gut microbiota and faecal metabolites. Matricin was positively correlated with Bacteroides and negatively correlated with Actinobacteria; protorifamycin I was negatively correlated with Actinobacteria; epothilone A was negatively correlated with Actinobacteria and positively correlated with Firmicutes; PA was positively correlated with Bacteroides and negatively correlated with Firmicutes; and cristacarpin was positively correlated with Actinobacteria; however, this correlation relationship does not imply causality.

CONCLUSIONS

This study used joint metagenomics and metabolomics analyses to elucidate the relationship between gut microbiota and faecal metabolites in different glycemic groups, and the result suggested that metabolic disorders and gut microbiota dysbiosis occurred in Uyghur T2DM and IGR. The results provide a theoretical basis for studying the pathological mechanism for further research.

Strategic Approach for Prioritising Local and Regional Sanitation Interventions for Reducing Global Antibiotic Resistance

Globally increasing antibiotic resistance (AR) will only be reversed through a suite of multidisciplinary actions (One Health), including more prudent antibiotic use and improved sanitation on international scales. Relative to sanitation, advanced technologies exist that reduce AR in waste releases, but such technologies are expensive, and a strategic approach is needed to prioritize more affordable mitigation options, especially for Low- and Middle-Income Countries (LMICs). Such an approach is proposed here, which overlays the incremental cost of different sanitation options and their relative benefit in reducing AR, ultimately suggesting the “next-most-economic” options for different locations. When considering AR gene fate versus intervention costs, reducing open defecation (OD) and increasing decentralized secondary wastewater treatment, with condominial sewers, will probably have the greatest impact on reducing AR, for the least expense. However, the best option for a given country depends on the existing sewerage infrastructure. Using Southeast Asia as a case study and World Bank/WHO/UNICEF data, the approach suggests that Cambodia and East Timor should target reducing OD as a national priority. In contrast, increasing decentralized secondary treatment is well suited to Thailand, Vietnam and rural Malaysia. Our approach provides a science-informed starting point for decision-makers, for prioritising AR mitigation interventions; an approach that will evolve and refine as more data become available.

Immigration and Acculturation: Impact on Health and Well-Being of Immigrants

Among migrants who arrived in the USA and Europe, communicable diseases such as dermatologic, gastrointestinal, and respiratory infections are frequent; non-communicable diseases including chronic diseases such as hypertension and diabetes, and vaccine-preventable diseases are also prevalent. Refugees are often not up to date on routine immunizations and screenings for chronic diseases and cancer. In addition, many immigrants have trauma-related mental health problems, which are often not addressed by the healthcare systems where they reside. Determining the healthcare needs of specific immigration groups should lead to the establishment of evidence-based guidelines for providing screening and healthcare services to immigrant populations, for the benefit of the individuals concerned, as well as the host countries.