Assessing viral metagenomics for the diagnosis of acute undifferentiated fever in returned travellers: a multicenter cohort study.

BACKGROUND: Up to 45% of febrile returning travellers remain undiagnosed after a thorough diagnostic work-up, even at referral centres. Although metagenomic next-generation sequencing (mNGS) has emerged as a promising tool, evidence of its usefulness in imported fever is very limited. METHODS: Travellers returning with fever were prospectively recruited in three referral clinics from November 2017 to November 2019. Unbiased mNGS optimised for virus detection was performed on serum samples of participants with acute undifferentiated febrile illness (AUFI), and results were compared to those obtained by reference diagnostic methods (RDM). RESULTS: Among 507 returned febrile travellers, 433(85.4%) presented with AUFI. Dengue virus (n = 86) and Plasmodium spp. (n = 83) were the most common causes of fever. 103/433(23.8%) AUFI remained undiagnosed at the end of the follow-up.Metagenomic next-generation sequencing unveiled potentially pathogenic microorganisms in 196/433(38.7%) AUFI. mNGS identifications were more common in patients with a shorter duration of fever (42.3% in ≤5 days vs 28.7% in >5 days, P = 0.005). Potential causes of fever were revealed in 25/103(24.2%) undiagnosed AUFI and 5/23(21.7%) travellers with severe undiagnosed AUFI. Missed severe aetiologies included eight bacterial identifications and one co-infection of B19 parvovirus and Aspergillus spp.Additional identifications indicating possible co-infections occurred in 29/316(9.2%) travellers with AUFI, and in 11/128(8.6%) travellers with severe AUFI, who had received a diagnosis through RDM. The most common co-infections detected in severe AUFI were caused by Gram-negative bacteria. Serum mNGS was unable to detect >50% of infectious diagnoses achieved by RDM and also yielded 607 non-pathogenic identifications. DISCUSSION: mNGS of serum can be a valuable diagnostic tool for selected travellers with undiagnosed AUFI or severe disease in addition to reference diagnostic techniques, especially during the first days of symptoms. Nevertheless, mNGS results interpretation presents a great challenge. Further studies evaluating the performance of mNGS using different sample types and protocols tailored to non-viral agents are needed.

Characterization of Latin American migrants at risk for Trypanosoma cruzi infection in a non-endemic setting. Insights into initial evaluation of cardiac and digestive involvement.

BACKGROUND: Trypanosoma cruzi causes Chagas disease (CD), a potentially fatal disease characterized by cardiac disorders and digestive, neurological or mixed alterations. T. cruzi is transmitted to humans by the bite of triatomine vectors; both the parasite and disease are endemic in Latin America and the United States. In the last decades, population migration has changed the classic epidemiology of T. cruzi, contributing to its global spread to traditionally non-endemic countries. Screening is recommended for Latin American populations residing in non-endemic countries. METHODS: The present study analyzes the epidemiological characteristics of 2,820 Latin American individuals who attended the International Health Service (IHS) of the Hospital Clinic de Barcelona between 2002 and 2019. The initial assessment of organ damage among positive cases of T. cruzi infection was analyzed, including the results of electrocardiogram (ECG), echocardiogram, barium enema and esophagogram. RESULTS: Among all the screened individuals attending the clinic, 2,441 (86.6%) were born in Bolivia and 1,993 (70.7%) were female. Of individuals, 1,517 (81.5%) reported previous exposure to the vector, which is a strong risk factor associated with T. cruzi infection; 1,382 individuals were positive for T. cruzi infection. The first evaluation of individuals with confirmed T. cruzi infection, showed 148 (17.1%) individuals with Chagasic cardiomyopathy, the main diagnostic method being an ECG and the right bundle branch block (RBBB) for the most frequent disorder; 16 (10.8%) individuals had a normal ECG and were diagnosed of Chagasic cardiomyopathy by echocardiogram. CONCLUSIONS: We still observe many Latin American individuals who were at risk of T. cruzi infection in highly endemic areas in their countries of origin, and who have not been previously tested for T. cruzi infection. In fact, even in Spain, a country with one of the highest proportion of diagnosis of Latin American populations, T. cruzi infection remains underdiagnosed. The screening of Latin American populations presenting with a similar profile as reported here should be promoted. ECG is considered necessary to assess Chagasic cardiomyopathy in positive individuals, but echocardiograms should also be considered as a diagnostic approach given that it can detect cardiac abnormalities when the ECG is normal.

Clinical evaluation of BioFire® multiplex-PCR panel for acute undifferentiated febrile illnesses in travellers: a prospective multicentre study.

BACKGROUND: Identifying the causes of Acute Undifferentiated Febrile Illness (AUFI) is key to improve the management of returning travellers with fever. We evaluated a BioFire®FilmArray® prototype panel of multiplex nucleic acid amplification tests (NAAT) targeting different relevant pathogens in travellers returning with fever. METHODS: Prospective, multicentre study to evaluate a prototype panel in whole blood samples of adult international travellers presenting with AUFI in three European travel Clinics/Hospitals (November 2017-November 2019). We evaluated 15 target analytes: Plasmodium spp., Plasmodium falciparum, Plasmodium knowlesi, Plasmodium malariae, Plasmodium ovale, Plasmodium vivax, chikungunya virus, dengue virus, Zika virus, Anaplasma phagocytophilum, Borrelia spp., Leptospira spp., Orientia tsutsugamushi, Rickettsia spp. and Salmonella spp. Results were compared with composite reference standards (CRSs) for each target infection, including direct methods [smear microscopy, rapid diagnostic test (RDT), reference NAAT and blood cultures] and indirect methods (paired serology). FINDINGS: Among 455 travellers with AUFI, 229 target infections were diagnosed; the prototype panel detected 143 (overall sensitivity and specificity of 62.5 and 99.8%, respectively). The panel identified all Plasmodium infections (n = 82). Sensitivity for dengue (n = 71) was 92.9, 80.8 and 68.5% compared with RDT, NAAT and CRS, respectively. Compared with direct methods and CRS, respectively, the prototype panel detected 4/4 and 4/6 chikungunya, 2/2 and 4/29 Leptospira spp., 1/1 and 1/6 O. tsutsugamushi and 2/2 and 2/55 Rickettsia spp., but 0/2 and 0/10 Zika, 0/1 and 0/11 A. phagocytophylum and 0/3 Borrelia spp. diagnosed by serology and only 1/7 Salmonella spp. diagnosed by blood cultures. 77/86 (89.5%) infections not detected by the panel were diagnosed by serology. INTERPRETATION: The prototype panel allowed rapid and reliable diagnosis for malaria, dengue and chikungunya. Further improvements are needed to improve its sensitivity for Zika and important travel-related bacterial infections.

Doxycycline responding illnesses in returning travellers with undifferentiated non-malaria fever: a European multicentre prospective cohort study.

BACKGROUND: Diagnosis of undifferentiated non-malaria fevers (NMF) in returning travellers is a great challenge. Currently, there is no consensus about the use of empirical antibiotics in returning travellers with undifferentiated NMF. Although studies in endemic areas showed that a wide range of pathogens implicated in undifferentiated NMF are treatable with doxycycline, the role of doxycycline in returning travellers with fever still has to be explored. METHODS: Prospective European multicentre cohort study of febrile international travellers (November 2017-November 2019). Immunological and molecular diagnostic techniques for doxycycline responding illnesses (DRI) agents such as Anaplasma phagocytophilum, spotted fever group Rickettsia spp., typhus group Rickettsia spp., Coxiella burnetii, Bartonella spp., Orientia tsutsugamushi, Borrelia miyamotoi, Borrelia recurrentis and Leptospira spp. were systematically performed in all patients with undifferentiated NMF. We estimated the prevalence and predictive factors of DRI in returning travellers with undifferentiated NMF. RESULTS: Among 347 travellers with undifferentiated NMF, 106 (30·5%) were finally diagnosed with DRI. Only 57 (53·8%) of the 106 DRI infections were diagnosed by the standard of care. The main causes of DRI were: 55 (51·9%) Rickettsia spp., 16 (15·1%) C. burnetii; 15 (14·2%) Bartonella spp.; 13 (12·3%) Leptospira spp. and 10 (9·5%) A. phagocytophilum. The only predictive factor associated with DRI was presenting an eschar (aOR 39·52, 95%CI 4·85-322·18). Features of dengue such as retro-orbital pain (aOR 0·40, 95%CI 0·21-0·76) and neutropenia (aOR 0·41, 95%CI 0·21-0·79) were negatively associated with DRI. CONCLUSIONS: Although DRI are responsible for 30% of undifferentiated NMF cases in travellers, those are seldom recognized during the first clinical encounter. Empirical treatment with doxycycline should be considered in returning travellers with undifferentiated fever and negative tests for malaria and dengue, particularly when presenting severe illness, predictive factors for rickettsiosis or no features of dengue.

Correction: Lack of efficacy of standard doses of ivermectin in severe COVID-19 patients.

[This corrects the article DOI: 10.1371/journal.pone.0242184.].

Estimating chagas disease prevalence and number of underdiagnosed, and undertreated individuals in Spain.

BACKGROUND: Chagas disease constitutes a public health problem, and Spain is the non-endemic country with the highest burden of disease outside the Americas. It represents a model for non-endemic countries regarding health policies to control the disease. This study is aimed to generate estimates of the T.cruzi prevalence and the number of undetected and untreated individuals with the infection in Spain and to compare them with the actual number of cases reported by official sources. METHODS: Using aggregate data collected from the literature and official sources (Spanish National Statistics Institute; Spanish Agency of Medicines and Medical Devices) from 2010 to 2018, this study estimates the number of Chagas disease cases, plus the underdiagnosis and undertreatment rates. RESULTS: We estimated that 55,367 out of 2,602,285 migrants originally from endemic countries were living with Chagas disease in Spain in 2018, accounting for a prevalence of 2.1%. Only 1% of these cases(613/455,566) were children aged 14 years or less resulting in a prevalence of 0.1%. Bolivian migrants accounted for 53.9% of the total estimated cases. The index of underdiagnosis and undertreatment were heterogeneous across different Spanish autonomous regions, but the overall index of underdiagnosis was around 71%, and the overall index of undertreatment was 82.5% in patients aged 15 years or older, and 60% in children. CONCLUSION: The burden of Chagas disease in Spain is considerable. Index of underdiagnosis and undertreatment are high, particularly in women of childbearing age, but they have improved in children since the implementation of antenatal screening programmes.

Causes of fever in returning travelers: a European multicenter prospective cohort study.

BACKGROUND: Etiological diagnosis of febrile illnesses in returning travelers is a great challenge, particularly when presenting with no focal symptoms [acute undifferentiated febrile illnesses (AUFI)], but is crucial to guide clinical decisions and public health policies. In this study, we describe the frequencies and predictors of the main causes of fever in travelers. METHODS: Prospective European multicenter cohort study of febrile international travelers (November 2017-November 2019). A predefined diagnostic algorithm was used ensuring a systematic evaluation of all participants. After ruling out malaria, PCRs and serologies for dengue, chikungunya and Zika viruses were performed in all patients presenting with AUFI ≤ 14 days after return. Clinical suspicion guided further microbiological investigations. RESULTS: Among 765 enrolled participants, 310/765 (40.5%) had a clear source of infection (mainly traveler's diarrhea or respiratory infections), and 455/765 (59.5%) were categorized as AUFI. AUFI presented longer duration of fever (p < 0.001), higher hospitalization (p < 0.001) and ICU admission rates (p < 0.001). Among travelers with AUFI, 132/455 (29.0%) had viral infections, including 108 arboviruses, 96/455 (21.1%) malaria and 82/455 (18.0%) bacterial infections. The majority of arboviral cases (80/108, 74.1%) was diagnosed between May and November. Dengue was the most frequent arbovirosis (92/108, 85.2%). After 1 month of follow-up, 136/455 (29.9%) patients with AUFI remained undiagnosed using standard diagnostic methods. No relevant differences in laboratory presentation were observed between undiagnosed and bacterial AUFI. CONCLUSIONS: Over 40% of returning travelers with AUFI were diagnosed with malaria or dengue, infections that can be easily diagnosed by rapid diagnostic tests. Arboviruses were the most common cause of AUFI (above malaria) and most cases were diagnosed during Aedes spp. high season. This is particularly relevant for those areas at risk of introduction of these pathogens. Empirical antibiotic regimens including doxycycline or azithromycin should be considered in patients with AUFI, after ruling out malaria and arboviruses.

Incidence of human granulocytic anaplasmosis in returning travellers with fever.

BACKGROUND: Although tick-borne pathogens have been reported as an important cause of imported fever, the incidence of Anaplasma phagocytophilum, the causative agent of human granulocytic anaplasmosis (HGA), in travellers is unknown. METHODS: We conducted a prospective cohort study to investigate the aetiologies of fever in returning travellers (November 2017-July 2019). Polymerase chain reaction for msp2 gene amplification and indirect immunofluorescence assay for A. phagocitophilum were performed in all returning travellers with undifferentiated non-malarial fever. RESULTS: Among 141 travellers included, 8 patients were diagnosed with probable or confirmed HGA. The overall incidence rate of HGA was 19.9 cases/1000 person-week of travel. The main destination of travel was Asia, accounting for 62.5% patients with HGA. Co-infections were found in 37.5% of patients with HGA. CONCLUSIONS: Diagnosis of HGA and empirical treatment with doxycycline should be considered in travellers with fever.

Relevance of screening for Chagas and viral hepatitis in Bolivian migrants.

OBJECTIVES: Given the scarcity of data regarding prevalence of various infectious diseases in Latin-American countries, our study aims to assess the burden of T. cruzi, S. stercoralis, HIV and viral hepatitis in Latin-American migrants, with a focus on Bolivian migrants. METHODS: We performed a retrospective observational study of 565 screening evaluations in adults (≥18 years) carried out at our International Healthcare referral service in Barcelona. We reviewed structured clinical records and microbiological results of patients attended between February 2012 and April 2015. RESULTS: The median age was 35 years and 74% were women. Of the population screened, 87% were of Bolivian origin. We found a 48% prevalence of T. cruzi, 16% of S. stercoralis, 0.2% of HIV, 0.2% HBV and 0.2% HCV. CONCLUSIONS: These results support the relevance of screening for T. cruzi and S. stercoralis in Bolivian migrants but challenge the pertinence of systematic screening for HBV in this population.

Lack of efficacy of standard doses of ivermectin in severe COVID-19 patients.

Ivermectin has recently shown efficacy against SARS-CoV-2 in-vitro. We retrospectively reviewed severe COVID-19 patients receiving standard doses of ivermectin and we compared clinical and microbiological outcomes with a similar group of patients not receiving ivermectin. No differences were found between groups. We recommend the evaluation of high-doses of ivermectin in randomized trials against SARS-CoV-2.

High Prevalence of Strongyloidiasis in Spain: A Hospital-Based Study.

Introduction: Strongyloidiasis is a prevailing helminth infection ubiquitous in tropical and subtropical areas, however, seroprevalence data are scarce in migrant populations, particularly for those coming for Asia. Methods: This study aims at evaluating the prevalence of S. stercoralis at the hospital level in migrant populations or long term travellers being attended in out-patient and in-patient units as part of a systematic screening implemented in six Spanish hospitals. A cross-sectional study was conducted and systematic screening for S. stercoralis infection using serological tests was offered to all eligible participants. Results: The overall seroprevalence of S. stercoralis was 9.04% (95%CI 7.76-10.31). The seroprevalence of people with a risk of infection acquired in Africa and Latin America was 9.35% (95%CI 7.01-11.69), 9.22% (7.5-10.93), respectively. The number of individuals coming from Asian countries was significantly smaller and the overall prevalence in these countries was 2.9% (95%CI -0.3-6.2). The seroprevalence in units attending potentially immunosuppressed patients was significantly lower (5.64%) compared with other units of the hospital (10.20%) or Tropical diseases units (13.33%) (p < 0.001). Conclusions: We report a hospital-based strongyloidiasis seroprevalence of almost 10% in a mobile population coming from endemic areas suggesting the need of implementing strongyloidiasis screening in hospitalized patients coming from endemic areas, particularly if they are at risk of immunosuppression.

[Recommendations for the screening for infectious diseases, mental health, and female genital mutilation in immigrant patients seen in Primary Care]. / Recomendaciones para el cribado de enfermedad infecciosa, salud mental y mutilación genital femenina en pacientes inmigrantes atendidos en Atención Primaria.

Immigrant health status may be improved if certain health conditions are identified early through the implementation of a screening program. This document presents the recommendations resulting from the Screening in immigrant population project (CRIBMI) aimed at implementing a screening program for infectious diseases (HIV, HBV, HCV, tuberculosis, strongyloidiasis, schistosomiasis and Chagas disease), as well as female genital mutilation and mental health (MH) in migrant population at Primary Care level. Screening recommendations were based on: coming from an endemic country for strongyloidiasis, schistosomiasis, and Chagas diseases; on a threshold level of prevalence for HIV (> 1%), HBV (> 2%), and HCV (> 2%), and on incidence (> 50 cases/100,000-inhabitants) for active tuberculosis in immigrants with < 5 years in Europe. Exploring the risk of FGM is recommended in women from countries where this practice is prevalent. Evaluation of MH status is recommended for people from areas of conflict and violence.

Geographic analysis and estimation of hepatitis C cases in migrant populations living in Spain: is a country-based screening strategy appropriate?

BACKGROUND: Spain needs to increase the number of new known cases in order to achieve the goal of eliminating hepatitis C virus (HCV) by 2030. The aim of this study was to estimate the number of HCV cases among the migrant population in Spain and propose different scenarios for micro-elimination strategies, targeting the most relevant migrant groups. METHODOLOGY: this epidemiological and demographic cross-sectional descriptive study employed a systematic approach to estimate the number of migrants infected by HCV in Spain. Estimates are based on demographic data and details the size of the foreign-born population living in every Spanish province and the anti-HVC+ prevalence rates in their respective countries of origin. RESULTS: in Spain, there are 100,268 estimated cases of anti-HCV+ among the total adult migrant population who live in the country. The estimated cases of anti-HCV+ among migrants from moderate-high endemic countries with a prevalence of ≥ 2%, > 3%, > 4% and > 5% are 48,979, 48,029, 24,176 and 15,646, respectively. The anti-HCV+ endemic countries (≥ 2%) that contribute to the highest number of estimated cases in Spain are Romania, Italy, Pakistan, Ukraine, Senegal, Russia and Nigeria. The autonomous communities with the highest prevalence and number of estimated anti-HCV+ cases among migrant population are Catalonia, Valencian Community, Madrid and Andalusia, respectively. CONCLUSION: these data show the need to establish HCV screening strategies for the migrant population in Spain and, particularly, in the most affected areas. The strategy should target those migrant communities with a higher prevalence and a higher number of estimated cases, such as people from Eastern Europe, Sub-Saharan Africa and Pakistan.