Executive Summary of the Spanish Guidelines for the Diagnosis and Management of Imported Febrile Illnesses from the Spanish Society of Tropical Medicine and International Health (SEMTSI), the Imported Pathology Group of the Spanish Society of Infectious Diseases and Clinical Microbiology (GEPI-SEIMC), the Spanish Society of Family and Community Medicine (SEMFYC), the Spanish Society of Primary Care Physicians (SEMERGEN) and the Spanish Society of Emergency Medicine (SEMES).

The Spanish Society of Tropical Medicine and International Health (SEMTSI), the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), the Spanish Society of Emergency Medicine (SEMES), the Spanish Society of Primary Care Physicians (SEMERGEN) and the Spanish Society of Family and Community Medicine (SEMFYC) have prepared a consensus statement on the diagnosis and management of patients with imported febrile illnesses. Twenty authors with different backgrounds and representing different healthcare perspectives (ambulatory primary care, travel and tropical medicine specialists, emergency medicine, hospital care, microbiology and parasitology and public health), identified 39 relevant questions, which were organised in 7 thematic blocks. After a systematic review of the literature and a thoughtful discussion, the authors prepared 125 recommendations, as well as several tables and figures to be used as a consulting tool. The present executive summary shows a selection of some of the most relevant questions and recommendations included in the guidelines.

Screening blood donors for malaria, can we increase the number of eligible donors? An observational retrospective study.

BACKGROUND: In non-endemic countries, malaria can be transmitted through blood donations from imported cases. To ensure standards of quality and safety of human blood, the European Union and Spanish national law, requires a deferral period, or a screening by immunological or genomic test among those donors with potential risk of malaria. Scientific societies, European Committee on Blood Transfusion, and Spanish Society of Haematology and Haemotherapy, refer only to the result of the immunological test. METHODS: An observational retrospective study was performed in potential donors with a positive immunological test for malaria done in the Regional Transfusion Center in Madrid and referred to the National Reference Unit for Tropical Diseases in Madrid between 2015-2020. At consultation a Polymerase Chain Reaction (PCR) for malaria was performed. RESULTS: During the study period, 121 possible donors attended for consultation at NRU-Trop. Median age: 38.5 (IQR:33-48); median time to consultation was 32 months (IQR:12.5-110). Eighty-two (67.8%) donors were migrants and thirty-nine were travellers (32.2%). ELISA values were available for 109 subjects (90.1%), 56 individual left malaria endemic area > 3 years before. All donors tested negative for Plasmodium spp PCR test (n = 121, 100%). CONCLUSIONS: None of the subjects with a positive immunologic test deferred as blood donors had a positive genomic test. The presence of Plasmodium spp in collected blood was not detected by molecular techniques. To avoid the loss of potential blood donors, especially those with low incidence red blood cell antigens, as more precise microbiology techniques become available, updating the existing legislation becomes necessary to increase the availability of donated blood.

Real-life application of a stratification model for HIV care.

INTRODUCTION: HIV infection has become a chronic disease with a good long-term prognosis, necessitating a change in the care model. For this study, we applied a proposal for an Optimal Care Model (OCM) for people with HIV (PHIV), which includes tools for assessing patient complexity and their classification into profiles to optimize care provision. METHODS: Observational, cross-sectional, and retrospective study. Adult PHIV treated at the Tropical Medicine consultations at Ramón y Cajal Hospital from January 1 to June 30, 2023, were included. The complexity calculation and the stratification into profiles for each patient were done according to the OCM. RESULTS: Ninety-four participants were included, 76.6% cisgender men, with a median age of 41 years (range 23-76). Latin America and Africa were the main regions of origin (72.4%). 98% had an undetectable HIV viral load. The degree of complexity was 78.7% low, 11.7% medium, 1% high, and 8.5% extreme. The predominant profile was blue (64.9%), followed by lilac (11.7%), purple (6.3%), and green (4.3%). 7.4% were unclassifiable, of whom 57.2% had high/extreme complexity. Among the unclassifiable, mental health problems were the most common. CONCLUSIONS: The OCM tools for People Living with HIV (PLWH) allow for the classification and stratification of most patients in a consultation with a non-standard population. Patients who did not fit into the pre-established profiles presented high complexity. Creating a profile focused on mental health or mixed profiles could facilitate the classification of more patients.

Efficacy and safety of fexinidazole for treatment of chronic indeterminate Chagas disease (FEXI-12): a multicentre, randomised, double-blind, phase 2 trial.

BACKGROUND: More than six million people worldwide, particularly in vulnerable communities in Latin America, are infected with Trypanosoma cruzi, the causative agent of Chagas disease. Only a small portion have access to diagnosis and treatment. Both drugs used to treat this chronic, neglected infection, benznidazole and nifurtimox, were developed more than 50 years ago, and adverse drug reactions during treatment pose a major barrier, causing 20% of patients to discontinue therapy. Fexinidazole proved efficacious in an earlier, interrupted clinical trial, but the doses evaluated were not well tolerated. The present study evaluated fexinidazole at lower doses and for shorter treatment durations. METHODS: In this randomised, double-blind, phase 2 trial, we included adult patients (18-60 years old) with confirmed T cruzi infection by serology and PCR and without signs of organ involvement. We evaluated three regimens of fexinidazole-600 mg once daily for 10 days (6·0 g total dose), 1200 mg daily for 3 days (3·6 g), and 600 mg daily for 3 days followed by 1200 mg daily for 4 days (6·6 g)-and compared them with a historical placebo control group (n=47). The primary endpoint was sustained negative results by PCR at end of treatment and on each visit up to four months of follow-up. This study is registered with ClinicalTrials.gov, NCT03587766, and EudraCT, 2016-004905-15. FINDINGS: Between Oct 16, 2017, and Aug 7, 2018, we enrolled 45 patients (n=15 for each group), of whom 43 completed the study. Eight (19%) of 43 fexinidazole-treated patients reached the primary endpoint, compared with six (13%) of 46 in the historical control group. Mean parasite load decreased sharply following treatment but rebounded beginning 10 weeks after treatment. Five participants had seven grade 3 adverse events: carpal tunnel, sciatica, device infection, pneumonia, staphylococcal infection, and joint and device dislocation. Two participants discontinued treatment due to adverse events unrelated to fexinidazole. INTERPRETATION: The fexinidazole regimens in this study had an acceptable safety profile but did not prove effective against T cruzi infection. Development of fexinidazole monotherapy for treating T cruzi infection has been stopped. FUNDING: The Drugs for Neglected Diseases initiative.

Chagas Disease in Europe.

Chagas disease is currently present in many non-endemic countries and remains a neglected tropical disease globally. A review of the literature identified significant gaps and scarcity of updated information from European countries, with most studies reporting data from Spain and Italy. The index of underdiagnosis may be as high as 70%, affecting mainly females of child-bearing age. Standardized screening of fertile, non-pregnant, women from endemic countries and subsequent treatment is considered an essential strategy to control transmission and prevent new cases, yet no uniform legislation for screening risk groups exists. There is heterogeneity in Europe in terms of preventive strategies to avoid transfusion-related transmission of Chagas disease, not necessarily in line with the European directives, with some countries conducting systematic screening for T. cruzi infection in blood donors, whilst others rely on pre-transfusion questionnaires. The growing burden of the infection in resource-rich areas may provide an opportunity for progress in certain aspects of control and prevention. Options for improving screening strategies, management and linkage to care are reviewed.

Chagas disease is related to structural changes of the gut microbiota in adults with chronic infection (TRIPOBIOME Study).

BACKGROUND: The implications of the gut microbial communities in the immune response against parasites and gut motility could explain the differences in clinical manifestations and treatment responses found in patients with chronic Chagas disease. METHODOLOGY/PRINCIPAL FINDINGS: In this pilot prospective cross-sectional study, we included 80 participants: 29 with indeterminate CD (ICD), 16 with cardiac CD (CCD), 15 with digestive CD (DCD), and 20 controls without CD. Stool was collected at the baseline visit and faecal microbial community structure DNA was analyzed by whole genome sequencing. We also performed a comprehensive dietary analysis. Ninety per cent (72/80) of subjects were of Bolivian origin with a median age of 47 years (IQR 39-54) and 48.3% (29/60) had received benznidazole treatment. There were no substantial differences in dietary habits between patients with CD and controls. We identified that the presence or absence of CD explained 5% of the observed microbiota variability. Subjects with CD exhibited consistent enrichment of Parabacteroides spp, while for Enterococcus hirae, Lactobacillus buchneri and Megamonas spp, the effect was less clear once excluded the outliers values. Sex, type of visceral involvement and previous treatment with benznidazole did not appear to have a confounding effect on gut microbiota structure. We also found that patients with DCD showed consistent Prevotella spp enrichment. CONCLUSIONS: We found a detectable effect of Chagas disease on overall microbiota structure with several potential disease biomarkers, which warrants further research in this field. The analysis of bacterial diversity could prove to be a viable target to improve the prognosis of this prevalent and neglected disease.

Contribution of Low CD4 Cell Counts and High Human Immunodeficiency Virus (HIV) Viral Load to the Efficacy of Preferred First-Line Antiretroviral Regimens for Treating HIV Infection: A Systematic Review and Meta-Analysis.

We assessed whether low CD4 count and high viral load (VL) affect the response to currently preferred ART. We performed a systematic review of randomized, controlled clinical trials that analyzed preferred first-line ART and a subgroup analysis by CD4 count (≤ or >200 CD4/µL) or VL (≤ or >100 000 copies/mL). We computed the odds ratio (OR) of treatment failure (TF) for each subgroup and individual treatment arm. Patients with ≤200 CD4 cells or VL ≥100 000 copies/mL showed an increased likelihood of TF at 48 weeks: OR, 1.94; 95% confidence interval (CI): 1.45-2.61 and OR, 1.75; 95% CI: 1.30-2.35, respectively. A similar increase in the risk of TF was observed at 96 weeks. There was no significant heterogeneity regarding integrase strand transfer inhibitor or nucleoside reverse transcriptase inhibitor backbone. Our results show that CD4 <200 cells/µL and VL ≥100,000 copies/mL impair ART efficacy in all preferred regimens.

Screening of imported malaria infection in asymptomatic migrants from Sub-Saharan Africa: A retrospective analysis of a 2010-2019 cohort.

BACKGROUND: Up to 40% of cases of imported malaria in Europe are diagnosed in recently arrived migrants, who generally exhibit asymptomatic or mild symptoms and show low parasitaemia (submicroscopic). The study describes the prevalence of malaria infection among asymptomatic Sub-Saharan African migrants (ASSAM) and compares asymptomatic malaria-infected (AMI) vs non-malaria infected patients. METHODS: An observational, comparative, retrospective study was carried out in ASSAM who underwent a medical examination, between 2010 and 2019 at the National Reference Unit for Tropical Diseases (NRU-Trop) in Madrid, Spain. Medical examination and systematic screening protocol for infectious diseases, including screening for malaria infection by Polymerase Chain Reaction (PCR) was performed. RESULTS: During the study period, 632 out of 1061 ASSAM were screened for malaria, median age: 24 years (IQR:1-5); median time from arrival to diagnosis: 2 months (IQR:1-5). P. falciparum was the most frequent species: 61 patients (67.8%). Compared to non-malaria infected, AMI subjects had: higher rate of co-infection with S. stercoralis (41.1%VS 22.9%;p < 0.001) and filariae (8.9% VS 2.4%;p = 0.006), lower erythrocyte corpuscular volume (83.6 VS 84.4;p = 0.008) and lower levels of cholesterol (151.0 VS 167.3;p < 0.001). CONCLUSIONS: We observed a high prevalence of AMI among ASSAM. This highlights the need to consider routing screening of migrants from endemic areas and to study if such screening could avoid the potential morbidities associated with chronic infection, reduce morbi-mortality of acute malaria and the risk of transmission in host communities.

Use of benznidazole to treat chronic Chagas disease: An updated systematic review with a meta-analysis.

BACKGROUND: Approximately 6 million people worldwide are affected by Chagas disease, with many in the chronic phase of the disease (CCD). It is crucial to evaluate the effectiveness of benznidazole for CCD treatment. METHODS/PRINCIPAL FINDINGS: We updated a meta-analysis published in 2009 up to February 2021, including controlled trials (RCT) and prospective observational studies (OBS) that compared benznidazole vs placebo/no-treatment (P/nT). Main outcomes evaluated were clinical progression (CP) and seroreversion with subgroup analysis performed according to study design and participants' age. Parasitological response and safety were also described. We identified 879 articles and selected nine for inclusion (corresponding to eight studies). After adding the nine articles from the previous meta-analysis, 17 studies were analyzed corresponding to 6640 patients. The odds ratio (OR) for seroreversion in children treated with benznidazole vs P/nT was 38.3 (95%CI: 10.7-137) and 34.9 (95%CI: 1.96-624.09) in RCT and OBS, respectively. In adults the OR for seroreversion in OBS was 17.1 (95%CI: 2.3-129.1). CP was only evaluated in adults, where benznidazole did not demonstrate a beneficial effect: OR 0.93 (95%CI: 0.8-1.1) and OR 0.49 (95%CI:0.2-1.2) for RCT and OBS, respectively. Most outcomes were deemed to have a low level of certainty, except for the beneficial effect in children and the low efficacy in adults (moderate certainty). CONCLUSIONS: Benznidazole should be recommended for CCD in children, though this is only based on serological response and a moderate grade of evidence, while in adults benznidazole efficacy remains uncertain. More data on clinical efficacy of benznidazole in CCD is needed in both children and adults.

Imported fascioliasis in Spain: Report of 12 cases from the +REDIVI collaborative network (2009-2019).

BACKGROUND: There are few reports of imported fascioliasis in Spain. This study aimed to describe the characteristics of cases registered in +REDIVI network. METHODS: Observational, retrospective, descriptive study of imported fascioliasis cases registered in the +REDIVI, a multicenter collaborative network collecting information on imported infectious diseases in Spain, from October 2009 to May 2019. RESULTS: Of 25,203 cases of imported disease registered over the study period, 16 (0.063%) were fascioliasis, acquired mainly in Pakistan, Morocco, Bolivia, and Peru. Clinical, analytical, and therapeutic data were available for 12 cases (6 immigrants, 4 people visiting friends and relatives, 2 travelers). Eleven (91.6%) had eosinophilia. The most frequent symptoms were abdominal pain (n = 5) and cough (n = 5). Two cases (16.66%) were acute and 10 (83.33%) chronic. Two patients presented lung involvement, and four had other parasitic co-infections. Twelve cases (100%) were seropositive for Fasciola hepatica. Ten patients underwent a coproparasitological study, none of which detected Fasciola spp. eggs. The probable food origin (watercress) was confirmed in 3 cases (25%). Nine of the 10 patients treated with triclabendazole (90%) and one patient treated with praziquantel were considered to meet the criteria for cure. One patient was lost to follow-up. CONCLUSIONS: Fascioliasis is a rare imported parasitosis in Spain. Eosinophilia, along with geographical origin, is the main clue for diagnosis.

Trypanocidal treatment of Chagas disease.

Chagas disease is a neglected parasitosis caused by the protozoan parasite Trypanosoma cruzi. This infection is present in most Latin American countries, although, due to migratory movements, it is a growing cause for concern in non-endemic countries. The only two drugs currently available for its treatment-benznidazole and nifurtimox-were marketed 50 years ago. While they are very effective for acute and recent infection, and for the prevention of maternofoetal transmission, their efficacy declines in people who have chronic infection, especially those older than 18 years of age. In the presence of visceral involvement, parasiticidal treatment is of little or no value. The safety profile of both drugs is far from ideal, with frequent adverse events and high rates of drug discontinuation, mainly in adults. So far, new drugs and new strategies have not been shown to improve the results of the current nitroimidazoles, although the results are promising. In this review, we focus on the aspects that allow clinicians to make the best use of currently available drugs. In addition, we discuss new therapeutic options and ongoing research in the field.

Risk of Trypanosoma cruzi infection among travellers visiting friends and relatives to continental Latin America.

BACKGROUND: Chagas disease (CD) is regarded as a possible risk for travellers to endemic areas of continental Latin America (LA). The aim of the study is to determine the risk of Trypanosoma cruzi (TC) infection among travellers to CD endemic areas and to identify risk factors for acquiring TC infection. METHODS/PRINCIPAL FINDING: We designed a multicenter cross-sectional study among travellers in Spain (Badalona, Barcelona and Madrid). All available adults with laboratory confirmed proof of absence of TC infection from January 2012 to December 2015 were contacted. Participants referring a trip to LA after the negative TC screening were offered to participate. We performed a standardized questionnaire of travel related factors and measurement of TC antibodies in serum. A total of 971 participants with baseline negative TC serology were selected from the microbiology records. After excluding participants not meeting inclusion criteria, eighty participants were selected. Sixty three (78.8%) were female, and the median age was 38 (IQR 34-47) years. The reason to travel was visiting friends and relatives in 98.8% of the participants. The median duration of travel was 40 (IQR 30-60) days, with 4911 participants-day of exposure. Seventy seven cases (96.25%) participants had two negative TC serology tests after the travel, two cases (2.5%) had discordant serology results (considered false positive results) and one case was infected before travelling to LA. According to our data, the upper limit of the 95% confidence interval of the incidence rate of TC acquisition in travellers is 0.8 per 1000 participant-days. CONCLUSIONS/SIGNIFICANCE: Among 79 non-CD travellers to TC endemic areas, we found no cases of newly acquired TC infection. The incidence rate of TC acquisition in travellers to endemic countries is less than or equal to 0.8 per 1000 traveller-days.

COVID-19 and geographical area of origin.

OBJECTIVES: To describe and compare the main clinical characteristics and outcome measures in hospitalized patients with confirmed coronavirus disease 2019 (COVID-19) according to geographical area of origin. METHODS: A retrospective analysis of patients hospitalized with confirmed COVID-19 at a referral centre in Madrid, Spain, during March-May 2020 was performed. Recorded variables (age, gender, intensive care unit (ICU) admission, outcome), and geographical area of origin were compared for Europeans and non-Europeans (Latin Americans, Asians and Africans). RESULTS: In total, 2345 patients with confirmed COVID-19 hospitalized during the study period were included in the study. Of these, 1956 (83.4%) were European and 389 (16.6%) were non-European (of whom over 90%, 354/389, were Latin American). Non-Europeans were significantly younger than Europeans (mean 54 (SD 13.5) versus 70.4 (SD 15.1) years, p < 0.001); the majority were male (1420/2345, 60.6%), with no significant differences in gender between Europeans and non-Europeans (1197/1956 (61.2%) male in the European group versus 223/389 (57.3%) male in the non-European group, p 0.15). In-hospital mortality overall was higher in Europeans (443/1956, 22.7%) than in non-Europeans (40/389, 10.3%) (p < 0.001), but there were no significant differences when adjusted for age/gender (OR 1.27, 95% CI 0.86-1.88). Non-Europeans were more frequently admitted to ICU (71/389, 18.3%) compared with Europeans (187/1956, 9.6%) (p < 0.001) and a difference in ICU admission rate was also found when adjusted for age/gender (OR 1.43, 95% CI 1.03-1.98). CONCLUSIONS: No significant differences in mortality were observed between Europeans and non-Europeans (mainly Latin Americans), but an increase in ICU admission rate was found in non-Europeans.

Travelling with HIV in the XXI century: Case report and narrative review.

The number of migrants and travellers has grown in recent decades. This phenomenon is also true of people living with HIV, given their much-improved life expectancy and quality of life. A significant number of travellers with HIV are migrants returning to their home countries to visit friends and relatives (VFRs). This population constitutes a high-risk group because they travel for longer and often to rural and remote areas and have closer contact with the local population. In this review we discuss the sociodemographic characteristics of travellers with HIV, the differences between conventional travellers and VFRs, and the risks of HIV acquisition and transmission during travel. We also present the most relevant travel-associated illnesses and highlight the particularities of pre-travel advice given to this population, including immunosuppression, responses to vaccines, high incidence of comorbidities, drug interactions, legal and language barriers. The need to integrate these factors based on far less evidence than that available for the general population makes pre-travel advice for travellers with HIV genuinely challenging.

Trypanocidal treatment of Chagas disease.

Chagas disease is a neglected parasitosis caused by the protozoan parasite Trypanosoma cruzi. This infection is present in most Latin American countries, although, due to migratory movements, it is a growing cause for concern in non-endemic countries. The only two drugs currently available for its treatment-benznidazole and nifurtimox-were marketed 50 years ago. While they are very effective for acute and recent infection, and for the prevention of maternofoetal transmission, their efficacy declines in people who have chronic infection, especially those older than 18 years of age. In the presence of visceral involvement, parasiticidal treatment is of little or no value. The safety profile of both drugs is far from ideal, with frequent adverse events and high rates of drug discontinuation, mainly in adults. So far, new drugs and new strategies have not been shown to improve the results of the current nitroimidazoles, although the results are promising. In this review, we focus on the aspects that allow clinicians to make the best use of currently available drugs. In addition, we discuss new therapeutic options and ongoing research in the field.

Zika among international travellers presenting to GeoSentinel sites, 2012-2019: implications for clinical practice.

INTRODUCTION: International travellers contribute to the rapid spread of Zika virus (ZIKV) and its sentinel identification globally. We describe ZIKV infections among international travellers seen at GeoSentinel sites with a focus on ZIKV acquired in the Americas and the Caribbean, describe countries of exposure and traveller characteristics, and assess ZIKV diagnostic testing by site. METHODS: Records with an international travel-related diagnosis of confirmed or probable ZIKV from January 2012 through December 2019 reported to GeoSentinel with a recorded illness onset date were included to show reported cases over time. Records from March 2016 through December 2019 with an exposure region of the Americas or the Caribbean were included in the descriptive analysis. A survey was conducted to assess the availability, accessibility and utilization of ZIKV diagnostic tests at GeoSentinel sites. RESULTS: GeoSentinel sites reported 525 ZIKV cases from 2012 through 2019. Between 2012 and 2014, eight cases were reported, and all were acquired in Asia or Oceania. After 2014, most cases were acquired in the Americas or the Caribbean, a large decline in ZIKV cases occurred in 2018-19.Between March 2016 and December 2019, 423 patients acquired ZIKV in the Americas or the Caribbean, peak reporting to these regions occurred in 2016 [330 cases (78%)]. The median age was 36 years (range: 3-92); 63% were female. The most frequent region of exposure was the Caribbean (60%). Thirteen travellers were pregnant during or after travel; one had a sexually acquired ZIKV infection. There was one case of fetal anomaly and two travellers with Guillain-Barré syndrome. GeoSentinel sites reported various challenges to diagnose ZIKV effectively. CONCLUSION: ZIKV should remain a consideration for travellers returning from areas with risk of ZIKV transmission. Travellers should discuss their travel plans with their healthcare providers to ensure ZIKV prevention measures are taken.

Rabies postexposure prophylaxis in international travellers: Results from a Spanish travellers referral unit.

BACKGROUND: Rabies represents a major public health issue for travellers because pretravel preexposure (PrEP) rabies vaccination is not routinely indicated. For those unvaccinated, adequate postexposure prophylaxis (PEP), including rabies immunoglobulin (RIG) if needed, is the only effective method to prevent this fatal disease. METHODS: Descriptive retrospective study at a National Referral Unit for Tropical and Travel Medicine in Madrid, Spain, among travellers treated with PEP for rabies (January 2012-December 2017). Demographic, clinical and management data were reviewed. RESULTS: 168 patients were treated for possible rabies exposure (53% females, median age 35 years; IQR: 31-42). Southeast Asia accounted for more than half of the cases (N=86, 57.3%; CI 95% 49-65%). Dogs were the primary animal involved (n=67, 44.9%; CI 37-53%). After the bite, in half of the cases (n=88, 52.4%; CI 44-60%) PEP rabies vaccine was started abroad, and the vaccine plus RIG in about 10% (n=22, 13.1%; CI: 8-19%). Most of patients classified as category III did not received RIG at all (n=88, 69.3% CI: 60-77%). CONCLUSIONS: Although indicated, most travellers did not receive RIG abroad, nor appropriate first doses of PEP. Clinicians should be aware of the importance of appropriate PrEP in selected individuals.