Travel and migration associated infectious diseases morbidity in Europe, 2008

A systematic review and meta-analysis of sexually transmitted infections and blood-borne viruses in travellers

BACKGROUND

Sexually transmitted infections (STIs) and blood-borne viruses (BBVs) impose a global health and economic burden. International travellers facilitate the spread of infectious diseases, including STIs. Hence, this review assessed the prevalence/proportionate morbidity of travellers with STIs and sexually transmitted BBVs and factors associated with the infection in this population.

METHODS

PubMed, Scopus, Web of Science, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase and Cochrane Library were searched from inception of the databases until November 2022. Published analytical observational studies reporting the prevalence/proportionate morbidity of travellers with STIs and factors associated with STIs by type of traveller [i.e. tourists, business travellers, students, visiting friends or relatives (VFRs), international truck drivers, backpackers, expatriates and men who have sex with men (MSM)] were included. The selection of articles, data extraction and risk of bias assessment were conducted by two independent reviewers. Meta-analyses were conducted for each STI by clinical presentation and type of traveller.

RESULTS

Thirty-two studies (n = 387 731 travellers) were included; 19 evaluated the proportionate morbidity of STIs among symptomatic travellers, while 13 examined the prevalence of STIs in asymptomatic travellers. The highest proportionate morbidity was found among VFRs (syphilis, 1.67%; 95% CI: 1.03-2.81%), backpackers (Chlamydia trachomatis, 6.58%; 95% CI: 5.96-7.25%) and MSM (HIV [2.50%;95% CI: 0.44-12.88%], gonorrhoea [4.17%; 95% CI: 1.1.5-13.98%], lymphogranuloma venereum [4.17%;95% CI: 1.1.5-13.98%] and HAV [20.0%; 95% CI: 14.99-26.17%]). The highest prevalence of STIs among asymptomatic were found in MSM (HIV [25.94%; 95% CI: 22.21-30.05%] and HBV [24.90%; 95% CI: 21.23-28.96%]) and backpackers (C. trachomatis, 3.92%; 95% CI: 2.72-5.32%). Short duration of the trip (<1 month), not having pre-travel consultation, travelling to Southeast Asia and being unvaccinated for HBV were identified as risk factors for STIs.

CONCLUSION

Strategies to prevent STIs and sexually transmitted BBVs should be discussed at pre-travel consultations, and recommendations should be prioritized in high-risk groups of travellers, such as backpackers, VFRs and MSMs. Additionally, healthcare providers should tailor recommendations for safe sex practices to individual travellers' unique needs.

Screening and routine diagnosis of mental disorders among migrants in primary care: A cross-sectional study

Background

Migrants in host countries are at risk for the development of mental health conditions. The two aims of the study were to describe routine diagnoses of mental disorders among migrant patients at primary healthcare level and the associated risk factors, and to test the utility of an innovative migrant mental health assessment by evaluating whether the health professionals followed the recommendations proposed by the clinical decision support system (CDSS) tool.

Methods

A cross-sectional study was carried out in eight primary care centres (PCCs) in four non-randomly selected health regions of Catalonia, Spain from March to December 2018. Routine health data and mental health diagnoses based on the International Classification of Diseases (10th edition), including mental, behavioural and neuro developmental disorders (F01-F99), symptoms and signs involving emotional state (R45), and sleep disorders (G47), were extracted from the electronic health records. The proportion of mental health conditions was estimated and logistic regression models were used to assess any possible association with mental health disorders. The utility of the mental health assessment was assessed with the proportion of questionnaires performed by health professionals for migrants fulfilling the mental health screening criterion (country of origin with an active conflict in 2017) and the diagnoses given to the screened patients.

Results

Of 14,130 migrants that visited any of the PCCs during the study period, 7,358 (52.1 %) were women with a median age of 38.0 years-old. There were 520/14,130 (3.7 %) migrant patients diagnosed with a mental disorder, being more frequent among women (342/7,358; 4.7 %, p-value < 0.001), migrants from Latin-America (177/3,483; 5.1 %, p < 0.001) and those who recently arrived in Spain (170/3,672; 4.6 %, p < 0.001). A lower proportion of mental disorders were reported in migrants coming from conflicted countries in 2017 (116/3,669, 3.2 %, p = 0.053).Out of the 547 mental health diagnoses reported in 520 patients, 69/14,130 (0.5 %) were mood disorders, 346/14,130 (2.5 %) anxiety disorders and 127/14,130 (0.9 %) sleeping disorders. Mood disorders were more common in migrants from Eastern Europe (25/2,971; 0.8 %, p < 0.001) and anxiety disorders in migrants from Latin-America (126/3,483; 3.6 %, p < 0.001), while both type of disorders were more often reported in women (p < 0.001).In the adjusted model, women (aOR: 1.5, [95 % CI 1.2-1.8, p < 0.001]), migrants with more than one visit to the health center during the study period (aOR: 4.4, [95 %CI 2.8-6.8, p < 0.001]) and who presented an infectious disease (aOR: 2.1, [95 %CI 1.5-3.1, p < 0.001]) had higher odds of having a mental disorder.Lastly, out of the 1,840 migrants coming from a conflicted country in 2017 who were attended in centres where the CDSS tool was implemented, 29 (1.6 %) had a mental health assessment performed and the tool correctly identified one individual.

Conclusions

Mental health is a condition that may be overlooked in migrants at primary healthcare. Interventions at this level of care must be reinforced and adapted to the needs and circumstances of migrants to ensure equity in health services.

Infections in travellers returning to the UK: a retrospective analysis (2015-2020)

BACKGROUND

Every year, many thousands of travellers return to the United Kingdom (UK) from visits to other countries and some will become unwell due to infections acquired abroad. Many imported infections have similar clinical presentations, such as fever and myalgia, so diagnostic testing is an important tool to improve patient management and outcomes. The aim of this study was to examine the demographics, travel history, presenting symptoms and diagnostic outcomes of referrals to the UK's specialist diagnostic Rare & Imported Pathogens Laboratory (RIPL) for the period 2015-2020.

METHODS

Anonymised clinical and laboratory data was extracted from RIPL's Laboratory Information Management System (LIMS) and cleaned prior to descriptive analysis of the data. Travel history data was mapped to one of eight world regions, while symptom data was categorised into presenting syndromes. Diagnostic data was categorised as either positive, equivocal or negative.

RESULTS

During the period 2015-2020, RIPL received 73 951 samples from 53 432 patients suspected of having infections that are rare in the UK. The most common age group for unwell returning travellers was 30-39 years and the most commonly reported travel destination was Southern and SE Asia. Dengue virus was the most diagnosed infection overall, followed by chikungunya, Zika, leptospirosis and spotted fever group Rickettsia. Dengue virus was among the top three most frequent diagnoses for all world regions except Europe and represented 62.5% of all confirmed/probable diagnoses.

CONCLUSIONS

None of the top five infections diagnosed by RIPL in travellers are vaccine-preventable, therefore understanding traveller demographics, destination-specific risk factors and encouraging preventative behaviours is the best available strategy to reduce the number of returning travellers who become infected. Prompt referral of acute samples with a detailed travel history, including purpose of travel and activities undertaken as well as dates and destinations can be a valuable tool in designing public health interventions and diagnostic algorithms.

Provision of Travel Health Advice Through Local Tourist Handlers: Perspectives of Safari Tour Operators in Uganda

BACKGROUND

The public health burden of travel related diseases (TRDs) remains significant despite the fact that most can be avoided, particularly with the assistance of local tourist handlers such as Safari Tour Operators' (STOs). The STO's are the immediate close contact with tourist groups, and yet their perspectives regarding provision of travel health advice are unknown in Uganda. This study was conducted to determine the level of knowledge, attitude, and practices of STOs regarding TRDs in Uganda.

METHODS

A cross sectional study was carried out among selected STOs in Kampala and Wakiso Districts using self-administered questionnaires.

RESULTS

The overall level of knowledge about travel health information was inadequate. Although 77.5% of the STOs were aware of some TRDs, the availability of travel health information or database in their organisations was not observed. Knowledge of the current TRDs in Uganda among the STOs was very low, with a few individuals mentioning yellow fever (9.7%), malaria (9.2%), cholera (9.2%), and HIV/AIDs (8.9%). Knowledge related to the sources of the travel health information was also low, with STOs (19.1%) and travel health clinics (14.9%) being mentioned as the main sources. The STOs had mostly positive attitude towards provision of travel health advice related to travellers, and all agreed that STOs should play a big role in the provision of travel health advice. First Aid and simple treatment options were mentioned as practices that STOs conducted to keep the travellers safe.

CONCLUSIONS

While the STOs are motivated to do the right thing and provide their clients with sound travel health advice, they have a limited awareness of the actual TRDs in Uganda. The STOs must be educated on pertinent travel health advice, and intra-travel disease and injury management. The responsible government and non-governmental entities in Uganda need to develop educational materials emphasising the relevance of travel health advice.

Non-Endemic Leishmaniases Reported Globally in Humans between 2000 and 2021—A Comprehensive Review

Leishmaniases are human and animal parasitic diseases transmitted by phlebotomine sand flies. Globalization is an important driver of the burden and in the current dynamics of these diseases. A systematic review of articles published between 2000 and 2021 was conducted using the PubMed search engine to identify the epidemiology and clinical management of imported human leishmaniases as a fundamental step to better manage individual cases and traveler and migrant health from a global perspective. A total of 275 articles were selected, representing 10,341 human imported cases. Identified drivers of changing patterns in epidemiology include conflict and war, as well as host factors, such as immunosuppression, natural and iatrogenic. Leishmania species diversity associated with different clinical presentations implies diagnostic and treatment strategies often complex to select and apply, especially in non-endemic settings. Thus, diagnostic and management algorithms for medical clinical decision support are proposed. Increased surveillance of non-endemic cases, whether in vulnerable populations such as refugees/migrants and immunocompromised individuals or travelers, could improve individual health and mitigate the public health risk of introducing Leishmania species into new areas.

Underestimation of travel-associated risks by adult and paediatric travellers compared to expert assessment: A cross-sectional study at a hospital-based family pre-travel clinic

BACKGROUND

Travellers' perception of their risk for acquiring travel-related conditions is an important contributor to decisions and behaviors during travel. In this study, we aimed to assess the differences between traveller-perceived and expert-assessed risk of travel-related conditions in children and adults travelling internationally and describe factors that influence travellers' perception of risk.

METHODS

Children and adults were recruited at the Hospital for Sick Children's Family Travel Clinic between October 2014 and July 2015. A questionnaire was administered to participants to assess their perceived risk of acquiring 32 travel-related conditions using a 7-point Likert scale. Conditions were categorized as vector-borne diseases, vaccine-preventable diseases, food and water borne diseases, sexually transmitted infections and other conditions. Two certified travel medicine experts reviewed each patient's chart and assigned a risk score based on the same 7-point Likert scale. Traveller and expert risk scores were compared using paired t-tests.

RESULTS

In total, 207 participants were enrolled to participate in this study, 97 children (self-reported, n = 8; parent-reported, n = 89), and 110 adults. Travel-related risk for adults and parents answering for their children were significantly underestimated when compared to expert-assessed risk for 26 of the 32 assessed conditions. The underestimated conditions were the same for both adults and parents answering for children. Travel-related risk was not over-estimated for any condition.

CONCLUSIONS

Adults underestimated their children's and their own risk for most travel-related conditions. Strategies to improve the accuracy of risk perception of travel-related conditions by travellers are needed to optimize healthy travel for children and their families.

Implications of a travel connectivity-based approach for infectious disease transmission risks in Oceania

INTRODUCTION

The increase in international travel brought about by globalisation has enabled the rapid spread of emerging pathogens with epidemic and pandemic potential. While travel connectivity-based assessments may help understand patterns of travel network-mediated epidemics, such approaches are rarely carried out in sufficient detail for Oceania where air travel is the dominant method of transportation between countries.

DESIGN

Travel data from the Australian Bureau of Statistics, Stats NZ and the United Nations World Tourism Organization websites were used to calculate travel volumes in 2018 within Oceania and between Oceania and the rest of the world. The Infectious Disease Vulnerability Index (IDVI) was incorporated into the analysis as an indicator of each country's capacity to contain an outbreak. Travel networks were developed to assess the spread of infectious diseases (1) into and from Oceania, (2) within Oceania and (3) between each of the Pacific Island Countries and Territories (PICTs) and their most connected countries.

RESULTS

Oceania was highly connected to countries in Asia, Europe and North America. Australia, New Zealand and several PICTs were highly connected to the USA and the UK (least vulnerable countries for outbreaks based on the IDVI), and to China (intermediate low vulnerable country). High variability was also observed between the PICTs in the geographical distribution of their international connections. The PICTs with the highest number of international connections were Fiji, French Polynesia, Guam and Papua New Guinea.

CONCLUSION

Travel connectivity assessments may help to accurately stratify the risk of infectious disease importation and outbreaks in countries depending on disease transmission in other parts of the world. This information is essential to track future requirements for scaling up and targeting outbreak surveillance and control strategies in Oceania.

Histopathology of non-IBD colitis practical recommendations from pathologists of IG-IBD Group

Pathologists are often called upon to diagnose colitides that differ from the two main forms of inflammatory bowel disease (IBD). These non-IBD colitides include infectious colitis, microscopic colitis, ischemic colitis, eosinophilic colitis, autoimmune enterocolitis, segmental colitis associated with diverticulosis, drug-induced colitis, radiation colitis and diversion colitis. The diagnosis of these different disease entities relies on the histopathological examination of endoscopic biopsies of the gastrointestinal tract. This paper reviews the main histomorphological characteristics of the various Non-IBD colitides.

Promoting, seeking, and reaching vaccination services: A systematic review of costs to immunization programs, beneficiaries, and caregivers

INTRODUCTION

Understanding the costs to increase vaccination demand among under-vaccinated populations, as well as costs incurred by beneficiaries and caregivers for reaching vaccination sites, is essential to improving vaccination coverage. However, there have not been systematic analyses documenting such costs for beneficiaries and caregivers seeking vaccination.

METHODS

We searched PubMed, Scopus, and the Immunization Delivery Cost Catalogue (IDCC) in 2019 for the costs for beneficiaries and caregivers to 1) seek and know how to access vaccination (i.e., costs to immunization programs for social mobilization and interventions to increase vaccination demand), 2) take time off from work, chores, or school for vaccination (i.e., productivity costs), and 3) travel to vaccination sites. We assessed if these costs were specific to populations that faced other non-cost barriers, based on a framework for defining hard-to-reach and hard-to-vaccinate populations for vaccination.

RESULTS

We found 57 studies describing information, education, and communication (IEC) costs, social mobilization costs, and the costs of interventions to increase vaccination demand, with mean costs per dose at $0.41 (standard deviation (SD) $0.83), $18.86 (SD $50.65) and $28.23 (SD $76.09) in low-, middle-, and high-income countries, respectively. Five studies described productivity losses incurred by beneficiaries and caregivers seeking vaccination ($38.33 per person; SD $14.72; n = 3). We identified six studies on travel costs incurred by beneficiaries and caregivers attending vaccination sites ($11.25 per person; SD $9.54; n = 4). Two studies reported social mobilization costs per dose specific to hard-to-reach populations, which were 2-3.5 times higher than costs for the general population. Eight studies described barriers to vaccination among hard-to-reach populations.

CONCLUSION

Social mobilization/IEC costs are well-characterized, but evidence is limited on costs incurred by beneficiaries and caregivers getting to vaccination sites. Understanding the potential incremental costs for populations facing barriers to reach vaccination sites is essential to improving vaccine program financing and planning.

Deployment Infectious Disease Threats: IDCRP Initiatives and Vision Forward

BACKGROUND

Infectious diseases pose a significant threat to health and readiness of military personnel deployed globally during wartime and peacekeeping activities. Surveillance and improvement in mitigation through research of infectious disease threats remain an integral part of Force Health Protection. Herein, we review research efforts of the Infectious Disease Clinical Research Program related to deployment and travel-related infections.

METHODS

The objectives of the Deployment and Travel-Related Infections Research Area are to (1) provide epidemiologic and clinical data, including pathogen-specific estimates of disease incidence among deployed troops, (2) execute clinical trials and effectiveness studies to improve recommendations regarding prevention and treatment of infections during deployment, and (3) evaluate the knowledge and practice patterns of health care providers engaged in deployment/travel medicine and the impact on outcomes. The centerpiece protocol of the research area is the Deployment and Travel-Related Infectious Disease Risk Assessment, Outcomes, and Prevention Strategies cohort study (TravMil), which was initiated in 2010 and collects data on a broad range of deployment-related infections.

RESULTS

To date, 4,154 deployed military personnel and traveling Department of Defense (DoD) beneficiaries have been enrolled in TravMil. Surveillance data collected through the TravMil study provide assessment of deployment and travel-related infectious disease threats, and the effectiveness of mitigation strategies. The incidence of travelers' diarrhea, influenza-like illness, and undifferentiated febrile illness is 20.48%, 9.34%, and 6.16%, respectively. The cohort study also provides necessary infrastructure to execute clinical trials. The TrEAT TD clinical trial evaluated the effectiveness of single-dose antibiotic therapy for travelers' diarrhea in the deployed setting. When compared to levofloxacin, azithromycin was not inferior; however, inferiority was not demonstrated with use of single dose of rifaximin. The trial findings supported the development of a deployment-related health guideline for the management of acute diarrheal disease. A clinical trial evaluating the effectiveness of rifaximin for prevention for travelers' diarrhea (Prevent TD) is underway.

CONCLUSIONS

The research area has proven its ability to conduct impactful research, including the development of field-expedient diagnostics, the largest DoD multi-site travelers' diarrhea randomized control trial in peacetime and combat settings, and informed Force Health Protection guidance. The research area continues to provide surveillance data to military commands via an established collaborative network of military treatment facilities, DoD laboratories (both within and outside the continental United States), foreign militaries, and academia. The conduct of clinical and translational research in a deployment setting presents significant challenges, most notably in recruitment/enrollment and compliance with study-related procedures during deployment.

Imaging of toxocariasis

Several imaging modalities have now been employed to visualize the manifestations of larval Toxocara infection in hepatic, neurologic, ocular, renal, and other anatomical sites. This report reviews the usefulness and value of these individual imaging methods in diagnosis and follow-up of the different cases causing eosinophilic (granulomatous) infiltrations the liver, lungs, brain, heart, and eyes. Imaging provides a means of assisting in diagnosis and management in this infection where diagnosis by biopsy is often unlikely to capture an actual larva for the purpose of making a definitive diagnosis on the basis of larval morphology or DNA detection.

Low incidence of helminth infections (schistosomiasis, strongyloidiasis, filariasis, toxocariasis) among Dutch long-term travelers: A prospective study, 2008-2011

BACKGROUND

Despite the considerable burden of helminth infections in developing countries and increasing international travel, little is known about the risks of infection for travelers.

OBJECTIVE

We studied the attack and incidence rate of serology confirmed strongyloidiasis, filariasis, and toxocariasis among long-term travelers and associated factors. A second objective was to evaluate eosinophilia as a positive/negative predictive value (PPV/NPV) for a recent helminth infection.

METHODS

From 2008 to 2011, clients of the Public Health Service travel clinic planning travel to (sub)tropical countries for 12-52 weeks were invited to participate in a prospective study. Participants kept a weekly diary, recording itinerary, symptoms, and physician visits during travel and completed a post-travel questionnaire. Pre- and post-travel blood samples were serologically tested for the presence of IgG antibodies against Schistosoma species, Strongyloides stercoralis, filarial species, and Toxacara species and were used for a blood cell count. Factors associated with recent infection were analyzed using Poisson regression. Differences among groups of travelers were studied using chi square tests.

RESULTS

For the 604 participants, median age was 25 years (interquartile range [IQR]: 23-29), 36% were male, median travel duration was 20 weeks (IQR: 15-25), and travel purpose was predominantly tourism (62%). Destinations were Asia (45%), Africa (18%), and the Americas (37%). Evidence of previous infection was found in 13/604 participants: antibodies against Schistosoma spp. in 5 (0.8%), against S.stercoralis in 3 (0.5%), against filarial species in 4 (0.7%), and against Toxocara spp. in 1 (0.2%). Ten recent infections were found in 9 participants (3, 1, 6, 0 cases, in the above order), making the attack rates 0.61, 0.17, 1.1 and 0, and the incidence rates per 1000 person-months 1.5, 0.34, 2.6 and 0. The overall PPV and NPV of eosinophila for recent infection were 0 and 98%, respectively.

CONCLUSIONS

The risk of the helminth infections under study in this cohort of long-term travelers was low. Routine screening for eosinophilia appeared not to be of diagnostic value.

Navigating the jungles of tropical infectious gastrointestinal pathology: a pattern-based approach to the endoscopic biopsy

International travels and global human migration have had the unforeseen consequence of increasing the exposure of histopathologists in developed countries to the pathology of tropical infectious disease. The gastrointestinal tract (GIT) is often the primary site of infection due to the faecal-oral route of transmission and the high risk of exposure to contaminated water, food or soil when travelling to these regions. Whilst current microbiologic techniques are far more sensitive than histology in detecting infectious pathogens, the histopathologist nonetheless retains a pivotal role in diagnosing tropical GIT disease. This role entails evaluating endoscopic biopsies for any characteristic inflammatory pattern, identifying pathogens which may be present and excluding other look-alike pathologies. Recent advances in commercially available diagnostic modalities, including molecular techniques, have further broadened the scope of the histopathologist's armamentarium. This review outlines a practical pattern-based approach to diagnosing tropical GIT infections in endoscopic material, so as to assist pathologists less familiar with this spectrum of pathology.

The Epidemiology of Imported Acute Infectious Diseases in Zhejiang Province, China, 2011-2016: Analysis of Surveillance Data

To explore epidemiological characteristics of imported acute infectious diseases between 2011 and 2016 in Zhejiang province, China. Data of imported infectious diseases from 2011 to 2016 was collected from the China Information System for Disease Control and Prevention in Zhejiang province, and subsequently analyzed for epidemiological characteristics. A survey was conducted to investigate clinicians' abilities to diagnose these diseases in Zhejiang province. From 2011 to 2016, 1,241 cases of imported acute infectious disease were reported in Zhejiang province, including 1,078 malaria cases, 156 dengue cases, three chikungunya fever cases and four Zika cases. Between 2011 and 2016, incidences of these diseases increased (P < 0.001). For malaria, male adults for labor export were the most affected group. Seasonal fluctuation was not obvious. Plasmodium falciparum was the main malaria type (822 cases) and most cases were acquired from African Region (791/822, 96.1%). Plasmodium vivax cases (194 cases) were mainly from African Region (78/194, 40.2%) and South-East Asia Region (51/194, 26.3%). Meanwhile, for dengue, adults and tourists were the most affected groups. The incidence of dengue was particularly high in August and October. The percent of correct clinician responses in the survey of diagnosis knowledge was 54.6% (standard deviation = 21.0%); this percentage was particularly low in general practitioners and clinicians from township hospitals. The capabilities of clinicians to diagnose these diseases were low and should be improved. Efforts should be made in improving and disseminating proper preventive measures of high-risk populations, surveillance of imported cases, and prevention and control of local epidemics.

Intrinsic DNA curvature in trypanosomes

Background

Trypanosoma cruzi and Trypanosoma brucei are protozoan parasites causing Chagas disease and African sleeping sickness, displaying unique features of cellular and molecular biology. Remarkably, no canonical signals for RNA polymerase II promoters, which drive protein coding genes transcription, have been identified so far. The secondary structure of DNA has long been recognized as a signal in biological processes and more recently, its involvement in transcription initiation in Leishmania was proposed. In order to study whether this feature is conserved in trypanosomatids, we undertook a genome wide search for intrinsic DNA curvature in T. cruzi and T. brucei.

Results

Using a region integrated intrinsic curvature (RIIC) scoring that we previously developed, a non-random distribution of sequence-dependent curvature was observed. High RIIC scores were found to be significantly correlated with transcription start sites in T. cruzi, which have been mapped in divergent switch regions, whereas in T. brucei, the high RIIC scores correlated with sites that have been involved not only in RNA polymerase II initiation but also in termination. In addition, we observed regions with high RIIC score presenting in-phase tracts of Adenines, in the subtelomeric regions of the T. brucei chromosomes that harbor the variable surface glycoproteins genes.

Conclusions

In both T. cruzi and T. brucei genomes, a link between DNA conformational signals and gene expression was found. High sequence dependent curvature is associated with transcriptional regulation regions. High intrinsic curvature also occurs at the T. brucei chromosome subtelomeric regions where the recombination processes involved in the evasion of the immune host system take place. These findings underscore the relevance of indirect DNA readout in these ancient eukaryotes.

Electronic supplementary material

The online version of this article (10.1186/s13104-017-2908-y) contains supplementary material, which is available to authorized users.

The potential use of melatonin to treat protozoan parasitic infections: A review

Melatonin (N-acetyl-5-methoxytryptamine) is a circadian hormone produced in vertebrates by the pineal gland and other organs. Melatonin is believed to influence immune cells leading to modulation of the proliferative response of stimulated lymphocytes as well as cytokine production. Due to the antioxidant and immunomodulatory effects of melatonin, it is suggested that this molecule could be a therapeutic alternative agent to fight bacterial, viral, and parasitic infections by a variety of mechanisms. Herein, we review the effects of melatonin on the cell biology of protozoan parasites and host's immune response. In toxoplasmosis, African trypanosomiasis and Chagas' disease, melatonin enhances host's immune response against the parasite via regulating the secretion of inflammatory mediators. In amoebiasis, melatonin reduces the amoebic lesions as well as increasing the leukophagocytosis and the number of dead amoebae. In giardiasis, serum melatonin levels are elevated in these patients; this suggests a positive correlation between the level of melatonin and phagocytic activity in the G. duodenalis infected patients, possibly related to melatonin's immunomodulatory effect. In leishmaniasis, melatonin arrests parasite replication accompanied by releasing mitochondrial Ca²⁺ into the cytosol, increasing the level of mitochondrial nitrites as well as reducing superoxide dismutase (SOD) activity. In malaria, melatonin synchronizes the Plasmodium cell cycle via modulating cAMP-PKA and IP3-Ca²⁺ pathways. Thus, simultaneous administration of melatonin agonists or giving pharmacological doses of melatonin may be considered a novel approach for treatment of malarial infection.

Redefining priorities towards graded travel-related infectious disease research

Our knowledge of the health problems and infections encountered by international travellers has evolved considerably in the past decades. The growth of global networks such as the GeoSentinel Surveillance network, TropNet Europe, EuroTravNet and networks based in North America have provided valuable information on the frequency of a wide array of travel-related diseases and accidents, including details on the destination of travel and trends over time. The information gained from these network studies has provided important data for the practice of travel medicine and in some instances for the development of practice guidelines. However, network data due to a lack of denominators usually cannot serve as a basis for a GRADE approach to guideline development. Although epidemiological network studies will continue to serve an important role in travel medicine we encourage an additional strong focus towards translational scientific research questions and towards the broader use of novel techniques to obtain more accurate epidemiological analyses to address the many unanswered questions in our field.

Increasing prevalence of infectious diseases in asylum seekers at a tertiary care hospital in Switzerland

OBJECTIVE

The increasing number of refugees seeking asylum in Europe in recent years poses new challenges for the healthcare systems in the destination countries. The goal of the study was to describe the evolution of medical problems of asylum seekers at a tertiary care centre in Switzerland.

METHODS

At the University Hospital Basel, we compared all asylum seekers during two 1-year time periods in 2004/05 and 2014/15 concerning demographic characteristics and reasons for referrals and hospitalizations.

RESULTS

Hundred ninety five of 2'544 and 516 of 6'243 asylum seekers registered at the national asylum reception and procedure centre Basel were referred to the University Hospital Basel in 2004/05 and 2014/15, and originated mainly from Europe (62.3%, mainly Turkey) and Africa (49.1%, mainly Eritrea), respectively. Median age was similar in both study periods (26.9 and 26.2 years). Infectious diseases in asylum seekers increased from 22.6% to 36.6% (p<0.001) and were the main reasons for hospitalizations (33.3% of 45 and 55.6% of 81 hospitalized patients, p = 0.017) in 2004/05 compared to 2014/15. The leading infectious diseases in hospitalized patients were tuberculosis (n = 4) and bacterial skin infections (n = 2) in 2004/05; Malaria (n = 9), pneumonia (n = 6), Chickenpox (n = 5), other viral infections (n = 5) and bacterial skin infections (n = 5) in 2014/15. Infectious diseases like malaria, cutaneous diphtheria, louseborne-relapsing fever or scabies were only found in the second study period. Almost one third of the admitted asylum seekers required isolation precautions with median duration of 6-9.5 days in both study periods.

CONCLUSIONS

The changing demography of asylum seekers arriving in Switzerland in the current refugee crisis has led to a shift in disease patterns with an increase of infectious diseases and the re-emergence of migration-associated neglected infections. Physicians should be aware of these new challenges.

A severe case of visceral leishmaniasis and liposomal amphotericin B treatment failure in an immunosuppressed patient 15 years after exposure

Background

Visceral leishmaniasis (VL) is a protozoan disease, which is responsible for 200.000–400.000 yearly infections worldwide. If left untreated, the fatality rate can be as high as 100% within 2 years. 90% of cases occur in just six countries: India, Bangladesh, Sudan, South Sudan, Ethiopia and Brazil. It is thus a disease rarely seen by physicians in Europe or North America. We report on the fatal case of VL in an 80-year-old immunosuppressed patient who presented with a latency of over 15 years after having visited an endemic region. This is the first report showing such extreme latency of VL in a European traveller. This case is furthermore unusual because it suggests primary treatment failure to liposomal amphotericin B.

Case presentation

An 80-year-old man who was on immunosuppressive treatment due to a non-specific inflammatory disease of the liver and kidney presented to our hospital with recurrent fever, fatigue and bloody diarrhoea. Histopathological analysis from a colon biopsy showed intracellular amastigotes. The diagnosis of VL was confirmed by polymerase-chain-reaction (PCR) of the colon biopsy. PCR was also performed in plasma, a bronchopulmonary lavage, a lymph node, liver and bone marrow biopsy and proved L. donovani as causative species. The disseminated infection was unresponsive to treatment with liposomal amphotericin B as recommended in immunosuppressed individuals despite stopping immunosuppressive treatment.

Conclusion

Imported cases of VL to non-endemic regions are increasing due to extensive international travel and migration. Furthermore, the increase of elderly patients and immunosuppressed individuals, secondary to HIV, post-transplant and chemotherapeutic agents, has resulted in an increase of VL also in endemic regions of Europe. It is thus important for physicians to be able to recognize the infection. This case also demonstrates treatment failure to amphotericin B, which was only a known problem in patients with HIV until now. The knowledge of this as a possible complication is important for specialists treating the disease.

Amphotericin B-loaded mannose modified poly(d,l-lactide-co-glycolide) polymeric nanoparticles for the treatment of visceral leishmaniasis: in vitro and in vivo approaches

Amphotericin B-loaded mannose modified PLGA nanoparticles are more efficacious in the treatment of visceral leishmaniasis in bothin vitroandin vivomodels than unmodified nanoformulations.

Frequency of infectious diseases in immigrants in a Western European country: a population-based study

The aim of this population-based study was to assess the incidence rates of infectious diseases in native- (Italian) and foreign-born (immigrants) populations in a North Italy area, in 2006-2010. Crude, age-specific incidence rates (IRs) and age-standardised rate ratios (SRRs) between foreign- and native-born subjects and their 95% confidence intervals (95% CI) were estimated. A total of 32,554 cases of infectious diseases were found (9.9% in foreign-born subjects). The highest SRRs between foreign- and nativeborn subjects were found for tuberculosis (SRR = 27.1; 95% CI 21.3-34.3), malaria (SRR = 21.1; 14.6-30.4), scabies (SRR = 8.5; 7.6-9.4), AIDS (SRR = 2.5; 1.8-3.4) and viral hepatitis B (SRR = 3.3; 2.1-5.2). The highest IR was found for AIDS in people from the Americas (IR = 4.57; 95% CI 2.2-8.4), for malaria and tuberculosis in people from Africa (IR = 13.89; 11.6-16.5 and IR = 11.87; 9.8-14.3 respectively). Therefore immigrants are at a higher risk of acquiring some common infectious diseases compared to the native population in Western European countries.

Parasitic and infectious diseases of the biliary tract in migrants and international travelers

In recent years, global and regional crises have led to extraordinary worldwide migration, accompanied by an increase in long-distance travel from Western countries. Both are linked to a rising incidence of rare parasitic and infectious diseases in first world countries, including in the biliary tract. Areas covered: A selective literature research in PubMed was performed to review the most important parasitic and infectious biliary diseases, which are caused by a wide variety of pathogens and may be latent over long periods, with chronic courses leading to cholangitis, hepatic failure or development of cholangiocarcinoma. Parasites such as Ascaris, Fasciola and Clonorchis/Opisthorchis are particularly important and may trigger biliary diseases or predisposition for bacterial superinfections. Viral or protozoal cholangitis is mainly a problem of impaired immunity. Expert commentary: Currently, these entities are still rare in migrants and long-distance travelers. However, a significant increase in Western countries has to be expected. Incidences are most likely underestimated because of protracted clinical latency. Diagnosis depends on the relevant pathogens, the host's immune status and the extent or distribution of biliary obstruction. Modern tomographic methods, ERCP and specific microbiological/parasitological/virological tests are of crucial diagnostic importance. Antimicrobial/antiparasitic/antiviral therapy along with ERCP and interventional sonography/radiology provide effective treatment options.

A closer look at travellers' infections abroad: Finnish nationwide data with incidences, 2010 to 2012

BACKGROUND

Although infections represent the most common health problem of travellers abroad, data on morbidity and incidences of various infections are scarce.

METHOD

Data on infections of Finnish travellers during 2010-2012 were retrieved from the database of SOS International, an assistance organization covering 95% of Finns requiring aid abroad. The study included 30,086 cases. For incidence calculation, the data were linked to the numbers of Finns visiting these regions during the same period as recorded by the Official Statistics of Finland.

RESULTS

The incidence of infections was particularly high in Africa, southern Europe plus the eastern Mediterranean, and Asia plus Oceania. The most frequent diagnoses were acute gastroenteritis (38.0%) and respiratory-tract infections (RTI) (34.5%), followed by infections of the ear (12.6%), skin or subcutaneous tissue (5.1%), urogenital tract (4.2%), eye (3.1%), and systemic febrile infections (2.2%). Vaccine-preventable diseases (VPD) accounted for 0.8% of cases, with varicella as most (49%) and influenza as second-most (27%) common.

CONCLUSIONS

Incidence of infections was higher in southern than in eastern and western Europe. Gastroenteritis and RTI proved the most frequent diagnoses, whereas systemic febrile infections were uncommon. Despite pre-travel immunizations, VPDs still occurred; pre-travel consultation should cover both varicella and influenza.

Brucella melitensis prosthetic joint infection in a traveller returning to the UK from Thailand: Case report and review of the literature

BACKGROUND

Brucella spp. prosthetic joint infections are infrequently reported in the literature, particularly in returning travellers, and optimal treatment is unknown.

METHOD

We describe a prosthetic joint infection (PJI) caused by Brucella melitensis in a traveller returning to the UK from Thailand, which we believe to be the first detailed report of brucellosis in a traveller returning from this area. The 23 patients with Brucella-related PJI reported in the literature are summarised, together with our case.

RESULTS

The diagnosis of Brucella-related PJI is difficult to make; only 30% of blood cultures and 75% of joint aspiration cultures were positive in the reported cases. Culture of intraoperative samples provides the best diagnostic yield. In the absence of radiological evidence of joint loosening, combination antimicrobial therapy alone may be appropriate treatment in the first instance; this was successful in 6/7 [86%] of patients, though small numbers of patients and the likelihood of reporting bias warrant caution in drawing any firm conclusions about optimal treatment. Aerosolisation of synovial fluid during joint aspiration procedures and nosocomial infection has been described.

CONCLUSIONS

Brucella-related PJI should be considered in the differential of travellers returning from endemic areas with PJI, including Thailand. Personal protective equipment including fit tested filtering face piece-3 (FFP3) mask or equivalent is recommended for personnel carrying out joint aspiration when brucellosis is suspected. Travellers can reduce the risk of brucellosis by avoiding unpasteurised dairy products and animal contact (particularly on farms and abattoirs) in endemic areas and should be counselled regarding these risks as part of their pre-travel assessment.

Imported brucellosis: A case series and literature review

BACKGROUND

Brucellosis is one of the main neglected zoonotic diseases. Several factors may contribute to the epidemiology of brucellosis. Imported cases, mainly in travellers but also in recently arrived immigrants, and cases associated with imported products, appear to be infrequently reported.

METHODS

Cases of brucellosis diagnosed at a referral unit for imported diseases in Europe were described and a review of the literature on imported cases and cases associated with contaminated imported products was performed.

RESULTS

Most imported cases were associated with traditional risk factors such as travel/consumption of unpasteurized dairy products in endemic countries. Cases associated with importation of food products or infected animals also occurred. Although a lower disease incidence of brucellosis has been reported in developed countries, a higher incidence may still occur in specific populations, as illustrated by cases in Hispanic patients in the USA and in Turkish immigrants in Germany. Imported brucellosis appears to present with similar protean manifestations and both classical and infrequent modes of acquisition are described, leading on occasions to mis-diagnoses and diagnostic delays.

CONCLUSIONS

Importation of Brucella spp. especially into non-endemic areas, or areas which have achieved recent control of both animal and human brucellosis, may have public health repercussions and timely recognition is essential.

Leprosy in England and Wales 1953-2012: surveillance and challenges in low incidence countries

OBJECTIVE

To review all notified cases of leprosy in England and Wales between 1953 and 2012.

DESIGN

National surveillance study of all reported cases.

SETTING

England and Wales.

OUTCOME

Number and characteristics of reported cases.

RESULTS

During this period, a total of 1449 leprosy cases were notified. The incidence fell from 356 new cases notified between 1953 and 1962 to 139 new cases between 2003 and 2012. Where data were available, leprosy was more common in men, 15-45 year olds and those from the Indian subcontinent. There was considerable undernotification in 2001-2012.

CONCLUSIONS

The high level of under-reporting indicates a need for improved surveillance in the UK. Public Health England, in collaboration with the UK Panel of Leprosy opinion, has revised the UK Memorandum on Leprosy in order to provide updated guidance on diagnostic procedures, treatment, case management, contact tracing and notification.

Travelers' Diarrhea in Children at Risk: An Observational Study From a Spanish Database

BACKGROUND

Gastrointestinal symptoms are a common cause of consultation about children traveling to or coming from developing countries. The aim of this study was to identify the risk factors associated with gastrointestinal syndrome in children who travel.

METHODS

A prospective observational analytical and multicenter study was performed within +Redivi, a Spanish Tropical Medicine network on imported infections, from January 2009 to December 2013. All participants aged 16 years and younger were included in the analysis. Ethical approval was obtained from all the participating centers.

RESULTS

A total of 606 children ≤16 years of age were registered in the +Redivi database during the study period. Median age was 8.7 years (interquartile range, 4.4-12.4 years), 65.8% (399/606) were immigrants, 90% were >2 years old and 54% were male. Median travel duration, excluding immigrants, was 50 days (interquartile range, 30-150 days). Children with gastrointestinal symptoms represented 13.5% (82/606) of total consultations. A significant association was found in bivariate analysis between gastrointestinal disorder and age <2 years (P < 0.01) and travel duration (P = 0.046). Immigrants had less gastrointestinal disorders than tourists (P < 0.05). The most prevalent infection was protozoan in 23.4% (142/606), and Giardia intestinalis was the most common pathogen in 10.1% (61/606) of total children. Independent risk factors for gastrointestinal symptoms were tourist and traveler child visiting friends and relatives (P = 0.03), travel duration <90 days (P = 0.008) and bacterial cause (P < 0.001).

CONCLUSIONS

Traveling children who developed a gastrointestinal syndrome represented 13.5% of the total pediatric consultations in +Redivi. Independent risk factors were tourist or traveler visiting friends and relatives, travel duration <90 days and bacterial infection. G. intestinalis was the most common infectious agent causing a gastrointestinal disorder in the traveler children.

Spectrum of Imported Infectious Diseases: A Comparative Prevalence Study of 16,817 German Travelers and 977 Immigrants from the Tropics and Subtropics

The aim of this study was to assess the spectrum of imported infectious diseases (IDs) among patients consulting the University of Munich, Germany, between 1999 and 2014 after being in the sub-/tropics. The analysis investigated complete data sets of 16,817 diseased German travelers (2,318 business travelers, 4,029 all-inclusive travelers, and 10,470 backpackers) returning from Latin America (3,225), Africa (4,865), or Asia (8,727), and 977 diseased immigrants, originating from the same regions (112, 654 and 211 respectively). The most frequent symptoms assessed were diarrhea (38%), fever (29%), and skin disorder (22%). The most frequent IDs detected were intestinal infections with species of Blastocystis(900),Giardia(730),Campylobacter(556),Shigella(209), and Salmonella(183). Also frequently observed were cutaneous larva migrans (379), dengue (257), and malaria (160). The number of IDs with significantly elevated proportions was higher among backpackers (18) and immigrants (17), especially among those from Africa (18) and Asia (17), whereas it was lower for business travelers (5), all-inclusive travelers (1), and those from Latin America (5). This study demonstrates a large spectrum of imported IDs among returning German travelers and immigrants, which varies greatly based not only on travel destination and origin of immigrants, but also on type of travel.

Social and Economic Burden of Human Leishmaniasis

Leishmaniasis continues to pose a major public health problem worldwide. With new epidemics occurring in endemic areas and the spread of the disease to previously free areas because of migration, tourism, and military activities, there is a great need for the development of an effective vaccine. Leishmaniasis is a disease of the poor, occurring mostly in remote rural villages with poor housing and little or no access to modern health-care facilities. In endemic areas, diagnosis of any form of leishmaniasis puts a huge financial strain on an already meagre financial resource at both the individual and community levels. Most often families need to sell their assets (land and livestock) or take loans from informal financial outfits with heavy interest rates to pay for the diagnosis and treatment of leishmaniasis. Here, we discuss the disease with special emphasis on its socioeconomic impact on the affected individual and community. In addition, we highlight the reasons why continued research aimed at developing an effective Leishmania vaccine is necessary.

Leishmaniasis: diagnostic issues in Europe

Leishmaniasis is a parasitic disease with clinical presentations that vary from asymptomatic infection to cutaneous, mucocutaneous or visceral disease. Recent epidemiological studies have shown an increased prevalence in Europe largely caused by an increase in international travel, difficulty eradicating leishmanial infection in AIDS patients, and the use of immunosuppressive medications. Clinical diagnosis may be challenging, and parasitological diagnosis entails the use of invasive procedures which may be unrevealing in the immunosuppressed. A number of less invasive tests for the detection of anti-leishmanial antibodies or leishmanial antigen are available but their sensitivity and specificity may vary with the infective species and results have to be interpreted in light of the clinical presentation. The availability of polymerase chain reaction assays amplifying leishmanial genetic material has been a major step forward in improving the diagnosis of leishmanial disease and the response to treatment.

Characteristics of HIV infected individuals traveling abroad. Results from the +REDIVI Collaborative Network

INTRODUCTION

The improvement in the prognosis of HIV infection, coupled with the increase in international travel and migration, has led to a rising number of HIV infected travelers. The objective of this study was to describe the epidemiological and clinical features of returning travelers, according to their HIV status.

METHODS

An observational prospective study was conducted including travelers and immigrants who traveled to visit friends and relatives (VFRs) registered in the +REDIVI collaborative network (January-2009; October-2014). +REDIVI is a national network that registers information regarding infections imported by travelers and immigrants at 21 different centers using a standardized protocol.

RESULTS

A total of 3464 travellers were identified: 72 were HIV+ (2.1%) and 3.392 HIV- (98%). HIV+ vs. HIV- travelers were often older (40.5y vs. 34.2y P=.001), VFRs (79.1% vs. 44.4%; P<.001), and consulted less for pre-travel advice (27% vs. 37%; P=.078). The main destinations for both groups were sub-Saharan Africa and Latin America. The most frequent reasons for consultation after travel were fever, request for a health examination, gastrointestinal complaints, and abnormal laboratory tests (mainly eosinophilia and anemia), which differed between groups. The most frequent diagnoses in HIV+ travelers were malaria (38.8%), newly diagnosed HIV infection (25%), and intestinal parasites (19.4%), while for HIV- travelers the main diagnoses were "healthy" (17.9%), malaria (14%), and intestinal parasites (17.3%).

CONCLUSIONS

The typical profile of an HIV+ traveler in +REDIVI was that of a VFR traveler who did not seek pre-travel advice and made high-risk trips. This may increase the chance of acquiring travel-related infections which may pose a special risk for HIV-infected travelers. The post-travel visit was a good opportunity for HIV infection screening.

Illness and injury of travellers abroad: Finnish nationwide data from 2010 to 2012, with incidences in various regions of the world

Binary file ES_Abstracts_Final_ECDC.txt matches

Complementary exams in the diagnosis of American tegumentary leishmaniasis

The diagnosis of American Tegumentary Leishmaniasis is a difficult but essential task when considering the high toxicity profile of the drugs available. Since the discovery of its etiologic agent, numerous diagnostic tests have been developed. None of the tests available today can be considered as the gold standard, since they do not add enough accuracy for the disease detection. Good epidemiological and clinical knowledge of the disease are fundamental precepts of the dermatology practice and precede the rational use of existing diagnostic tests. In this article we aim, through extensive literature review, to recall fundamental concepts of any diagnostic test. Subsequently, based on this information, we will weave important comments about the characteristics of existing diagnostic tests, including immunological tests such as Montenegro's skin test, serology and detection of parasites by direct examination, culture or histopathology. Finally we will discuss the new technologies and options for the diagnosis of Cutaneous Leishmaniasis. The molecular biology technique is considered a promising tool, promoting the rapid identification of the species involved. We also aim to educate dermatologists about a disease with high morbidity and assist in its difficult recognition.

Vaccination in the elderly: what can be recommended?

The age-associated increased susceptibility to infectious disease would suggest that vaccination should be a route to promote healthy aging and keep our seniors autonomous and independent. While vaccination represents a cost-effective and efficient strategy at community level, the ability of the immune system to mount a protective immune response is still unpredictable at the level of the individual. Thus, at a similar age, some individuals, including the elderly, might still be 'good' responders while some other, even younger, would definitely fail to mount a protective response. In this review, the current burden of vaccine-preventable diseases in the aging and aged population will be detailed with the aim to identify the ideal vaccine candidates over the age of 50 years. This article will conclude with potential strategies to reduce, as best as possible, this burden and the imperative need to overcome barriers in extending current vaccine coverage towards to a lifelong vaccine schedule.

Dengue: an update for clinicians working in non-endemic areas

Dengue is one of the most rapidly emerging viral infections globally, with 2.5 billion people now thought to live in dengue-endemic areas. In addition, reports of travel-related and autochthonous infections are increasing in non-endemic areas. Most patients with dengue experience a self-limiting febrile illness, but a proportion develop potentially life threatening complications around the time of fever clearance, including plasma leakage occasionally leading to shock, bleeding, and organ impairment. As dengue can present with non-specific symptoms of fever, headache and myalgias, the potential for misdiagnosis and inappropriate management by medical staff inexperienced with the disease is a concern. This short review will outline the latest World Health Organisation disease classification, potential complications, clinical assessment and management for clinicians working in non-endemic areas.

Travel-associated infection presenting in Europe (2008-12): an analysis of EuroTravNet longitudinal, surveillance data, and evaluation of the effect of the pre-travel consultation

BACKGROUND

Travel is important in the acquisition and dissemination of infection. We aimed to assess European surveillance data for travel-related illness to profile imported infections, track trends, identify risk groups, and assess the usefulness of pre-travel advice.

METHODS

We analysed travel-associated morbidity in ill travellers presenting at EuroTravNet sites during the 5-year period of 2008-12. We calculated proportionate morbidity per 1000 ill travellers and made comparisons over time and between subgroups. We did 5-year trend analyses (2008-12) by testing differences in proportions between subgroups using Pearson's χ(2) test. We assessed the effect of the pre-travel consultation on infection acquisition and outcome by use of proportionate morbidity ratios.

FINDINGS

The top diagnoses in 32 136 patients, ranked by proportionate morbidity, were malaria and acute diarrhoea, both with high proportionate morbidity (>60). Dengue, giardiasis, and insect bites had high proportionate morbidity (>30) as well. 5-year analyses showed increases in vector borne infections with significant peaks in 2010; examples were increased Plasmodium falciparum malaria (χ(2)=37·57, p<0·001); increased dengue fever (χ(2)=135·9, p<0·001); and a widening geographic range of acquisition of chikungunya fever. The proportionate morbidity of dengue increased from 22 in 2008 to 36 in 2012. Five dengue cases acquired in Europe contributed to this increase. Dermatological diagnoses increased from 851 in 2008 to 1102 in 2012, especially insect bites and animal-related injuries. Respiratory infection trends were dominated by the influenza H1N1 pandemic in 2009. Illness acquired in Europe accounted for 1794 (6%) of all 32 136 cases-mainly, gastrointestinal (634) and respiratory (357) infections. Migration within Europe was associated with more serious infection such as hepatitis C, tuberculosis, hepatitis B, and HIV/AIDS. Pre-travel consultation was associated with significantly lower proportionate morbidity ratios for P falciparum malaria and also for acute hepatitis and HIV/AIDS.

INTERPRETATION

The pattern of travel-related infections presenting in Europe is complex. Trend analyses can inform on emerging infection threats. Pre-travel consultation is associated with reduced malaria proportionate morbidity ratios and less severe illness. These findings support the importance and effectiveness of pre-travel advice on malaria prevention, but cast doubt on the effectiveness of current strategies to prevent travel-related diarrhoea.

FUNDING

European Centre for Disease Prevention and Control, University Hospital Institute Méditerranée Infection, US Centers for Disease Control and Prevention, and the International Society of Travel Medicine.

Unraveling Mycobacterium tuberculosis genomic diversity and evolution in Lisbon, Portugal, a highly drug resistant setting

Background

Multidrug- (MDR) and extensively drug resistant (XDR) tuberculosis (TB) presents a challenge to disease control and elimination goals. In Lisbon, Portugal, specific and successful XDR-TB strains have been found in circulation for almost two decades.

Results

In the present study we have genotyped and sequenced the genomes of 56 Mycobacterium tuberculosis isolates recovered mostly from Lisbon. The genotyping data revealed three major clusters associated with MDR-TB, two of which are associated with XDR-TB. Whilst the genomic data contributed to elucidate the phylogenetic positioning of circulating MDR-TB strains, showing a high predominance of a single SNP cluster group 5. Furthermore, a genome-wide phylogeny analysis from these strains, together with 19 publicly available genomes of Mycobacterium tuberculosis clinical isolates, revealed two major clades responsible for M/XDR-TB in the region: Lisboa3 and Q1 (LAM).

The data presented by this study yielded insights on microevolution and identification of novel compensatory mutations associated with rifampicin resistance in rpoB and rpoC. The screening for other structural variations revealed putative clade-defining variants. One deletion in PPE41, found among Lisboa3 isolates, is proposed to contribute to immune evasion and as a selective advantage. Insertion sequence (IS) mapping has also demonstrated the role of IS6110 as a major driver in mycobacterial evolution by affecting gene integrity and regulation.

Conclusions

Globally, this study contributes with novel genome-wide phylogenetic data and has led to the identification of new genomic variants that support the notion of a growing genomic diversity facing both setting and host adaptation.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-991) contains supplementary material, which is available to authorized users.

The effect of a multi-strain probiotic on the resistance toward Escherichia coli challenge in a randomized, placebo-controlled, double-blind intervention study

BACKGROUND

Several probiotic strains have been shown to enhance human resistance to infectious disease. It is speculated that these strains may impose this effect by excretion of anti-microbial components, by competing with pathogens for intestinal nutrients and/or mucosal adhesion sites or modulating the immune system.

OBJECTIVE

A parallel, double-blind, placebo-controlled 4-week intervention was performed in healthy males, to study the effect of a blend of probiotic bacteria (Lactobacillus helveticus Rosell-52, Lactobacillus rhamnosus Rosell-11, Bifidobacterium longum ssp. longum Rosell-175) and a probiotic yeast (Saccharomyces cerevisiae var boulardii CNCM I-1079) on enterotoxigenic Escherichia coli (ETEC) challenge. Primary outcomes studied were fecal ETEC excretion and total fecal output per day.

SUBJECTS/METHODS

Subjects were randomized to the probiotic (5 × 10(9) colony-forming units (CFUs); twice daily; n=30) or placebo group (twice daily; n=30). After 2 weeks, subjects were orally challenged with a live attenuated ETEC (3 × 10(9) CFU), previously demonstrated to induce mild, short-lived symptoms of a foodborne infection. Before and after ETEC challenge, subjects collected 24 h fecal samples. Compliance to study guidelines, stool consistency (Bristol Stool Score), stool frequency, and frequency and severity of gastrointestinal (GI) complaints were recorded by the subjects on a Daily Record Questionnaire.

RESULTS

ETEC challenge induced a significant increase in fecal ETEC excretion in both groups. However, a statistically significant increase in fecal output was only observed in the probiotic group. ETEC challenge resulted in a decrease in the percentage of fecal dry weight, and an increase in reported Bristol Stool Score, stool frequency and GI complaints. Dietary probiotics significantly decreased the percentage of fecal dry weight. In addition, ETEC increased C-reactive protein, total secretory Immunoglobulin A (IgA) and Immunoglobulin G Colonization Factor Antigen II.

CONCLUSION

Dietary probiotics did not increase resistance to oral attenuated ETEC challenge in human subjects.

Leishmaniasis in travelers: a literature review

Leishmaniasis is a vector-borne protozoan infection whose clinical spectrum ranges from asymptomatic infection to fatal visceral leishmaniasis. Over the last decades, an increase in imported leishmaniasis cases in developed, non-endemic countries, have been pointed-out from a review of the international literature. Among the possible causes are increasing international tourism, influx of immigrants from endemic regions and military operations. The main area for the acquisition of cutaneous leishmaniasis, especially for adventure travelers on long-term trips in highly-endemic forested areas, is represented from South America, whereas popular Mediterranean destinations are emerging as the main areas to acquire visceral variant. Leishmaniasis should be considered in the diagnostic assessment of patients presenting with a compatible clinical syndrome and a history of travel to an endemic area, even if this occurred several months or years before. Adventure travelers, researchers, military personnel, and other groups of travelers likely to be exposed to sand flies in endemic areas, should receive counseling regarding leishmaniasis and appropriate protective measures.

Leishmaniasis

Leishmaniasis remains an important neglected tropical infection that affects children more than adults. Geographical variation exists in the distribution of the various Leishmania species. Although the majority of the disease burden is found in poor countries, leishmaniasis is also endemic in several countries within Southern Europe. Transmission is mediated by the sandfly and may follow an anthroponotic or zoonotic cycle that also varies by region. The expression of leishmaniasis depends on a complex interaction between the type of infecting species and the host immune response. Infection may be asymptomatic or may manifest as cutaneous disease that is pleiomorphic in presentation, muco-cutaneous disease or the visceral form that may be lethal if untreated. Molecular techniques aid diagnosis especially in cases where amastigotes are not visualised. The efficacy of treatment varies with the type of infecting species and resistance patterns. Preventive measures aimed at avoiding sandfly bites are effective in reducing acquisition of leishmaniasis and should be promoted for travellers visiting endemic regions. The persistent lack of a vaccine against human leishmaniasis is a result of the poor investment in this neglected parasitosis.

Leptospirosis in Sub-Saharan Africa: a systematic review

BACKGROUND

Leptospirosis is an emerging zoonotic infection worldwide, possibly due to climate change and demographic shifts. It is regarded as endemic in Sub-Saharan Africa; however, for most countries scarce epidemiological data, if any, exist. The primary objectives were to describe the prevalence of leptospirosis in countries in Sub-Saharan Africa, and to develop options for prevention and control in the future.

METHODS

A systematic review was conducted to determine the prevalence of leptospirosis in Sub-Saharan Africa; the PRISMA guidelines were followed. Medline/PubMed, Embase, The Cochrane Library, Web of Science, BIOSIS Previews, the African Index Medicus, AJOL, and Google Scholar were searched.

RESULTS

Information about the prevalence and incidence of leptospirosis in humans is available, but remains scarce for many countries. Data are unavailable or outdated for many countries, particularly those in Central Africa. Most data are available from animals, probably due to the economic losses caused by leptospirosis in livestock. In humans, leptospirosis is an important cause of febrile illness in Sub-Saharan Africa. It concerns numerous serogroups, harboured by many different animal carriers.

DISCUSSION

A wide variety of data was identified. Prevalence rates vary throughout the continent and more research, especially in humans, is needed to reliably gauge the extent of the problem. Preventive measures need to be reconsidered to control outbreaks in the future.

Globalization of leptospirosis through travel and migration

Leptospirosis remains the most widespread zoonotic disease in the world, commonly found in tropical or temperate climates. While previous studies have offered insight into intra-national and intra-regional transmission, few have analyzed transmission across international borders. Our review aimed at examining the impact of human travel and migration on the re-emergence of Leptospirosis. Results suggest that alongside regional environmental and occupational exposure, international travel now constitute a major independent risk factor for disease acquisition. Contribution of travel associated leptospirosis to total caseload is as high as 41.7% in some countries. In countries where longitudinal data is available, a clear increase of proportion of travel-associated leptospirosis over the time is noted. Reporting patterns is clearly showing a gross underestimation of this disease due to lack of diagnostic facilities. The rise in global travel and eco-tourism has led to dramatic changes in the epidemiology of Leptospirosis. We explore the obstacles to prevention, screening and diagnosis of Leptopirosis in health systems of endemic countries and of the returning migrant or traveler. We highlight the need for developing guidelines and preventive strategies of Leptospirosis related to travel and migration, including enhancing awareness of the disease among health professionals in high-income countries.

Travel-related infection in European travelers, EuroTravNet 2011

BACKGROUND

Limited data exist on infectious diseases imported to various locations in Europe, particularly after travel within the continent.

METHODS

To investigate travel-related disease relevant to Europe that is potentially preventable through pre-travel intervention, we analyzed the EuroTravNet database of 5,965 ill travelers reported by 16 centers in "Western" Europe in 2011.

RESULTS

There were 54 cases of vaccine-preventable disease, mostly hepatitis A (n = 16), typhoid fever (n = 11), and measles (n = 8); 6 cases (including 3 measles cases) were associated with travel within "Western" Europe. Malaria was the most commonly diagnosed infection (n = 482, 8.1% of all travel-related morbidity). Among patients with malaria, the military most commonly received pre-travel advice (95%), followed by travelers for missionary, volunteer, research, or aid work (81%) but travelers visiting friends and relatives (VFRs) were least likely to receive pre-travel advice (21%). The vast majority (96%) of malaria patients were resident in "Western" Europe, but over half (56%) were born elsewhere. Other significant causes of morbidity, which could be reduced through advice and behavioral change, include Giardia (n = 221, 3.7%), dengue (n = 146, 2.4%), and schistosomiasis (n = 131, 2.2%). Of 206 (3.5%) travelers with exposure in "Western" Europe, 75% were tourists; the highest burden of disease was acute gastrointestinal infection (35% cases). Travel from "Eastern" Europe (n = 132, 2.2%) was largely associated with migration-related travel (53%); among chronic infectious diseases, tuberculosis was frequently diagnosed (n = 20). Travelers VFRs contributed the largest group of malaria patients (46%), but also had the lowest documented rate of pre-travel health advice in this subset (20%). Overall, 44% of nonimmigrant ill travelers did not receive pre-travel advice.

CONCLUSION

There is a burden of infectious diseases in travelers attending European health centers that is potentially preventable through comprehensive pre-travel advice, chemoprophylaxis, and vaccination. Targeted interventions for high-risk groups such as travelers VFRs and migration-associated travelers are of particular importance.

Morbidity and outcomes of foreign travelers in Zakynthos island, Greece: a retrospective study

Background

Although there is satisfactory recording of diseases affecting travelers visiting developing countries, little is known regarding morbidity of travelers when visiting developed countries. We sought to evaluate the morbidity of foreign travelers in Zakynthos, a popular Greek island attracting large number of foreign tourists every summer.

Methods

Data from foreign travelers that accommodated in Zakynthos and sought medical services from the private offices of Zante Medical Care from May 1 to October 30 2012 were retrospectively analyzed.

Results

Two thousand six hundred and eighty-eight patients were included in the study. The mean age (±SD) of the patients whom the age was recorded was 29.6 (±18.3) and 51.5% of them were from 18 to 40 years old. Disorders of the respiratory tract (32.7%), dermatologic conditions (21.1%), musculoskeletal injuries (16.4%), and gastrointestinal disorders (16.3%) were the four most prevalent clinical categories among patients. Ear disorder was the most common syndromic description (14.5%) among which 81.2% were ear infections; otitis externa and otitis media were diagnosed in 8.5% and 3.3% patients in total. The most common specific diagnosis was gastroenteritis (14.3%). Insect bite and sunburn were the most common diagnosis (6.5% and 3.8%, respectively) among patients with a dermatologic condition. Ear infection was the most common diagnosis in pediatric patients.

Conclusion

Disorders mainly of the upper respiratory tract were the predominant causes of illness among foreign travelers in Zakynthos. Traveler's diarrhea was the most common specific diagnosis but the prevalence within the total population was not very high.