COVID-19: an opportunity of systematic integration for Chagas disease. Example of a community-based approach within the Bolivian population in Barcelona.

BACKGROUND: As a Neglected Tropical Disease associated with Latin America, Chagas Disease (CD) is little known in non-endemic territories of the Americas, Europe and Western Pacific, making its control challenging, with limited detection rates, healthcare access and consequent epidemiological silence. This is reinforced by its biomedical characteristics-it is usually asymptomatic-and the fact that it mostly affects people with low social and financial resources. Because CD is mainly a chronic infection, which principally causes a cardiomyopathy and can also cause a prothrombotic status, it increases the risk of contracting severe COVID-19. METHODS: In order to get an accurate picture of CD and COVID-19 overlapping and co-infection, this operational research draws on community-based experience and participative-action-research components. It was conducted during the Bolivian elections in Barcelona on a representative sample of that community. RESULTS: The results show that 55% of the people interviewed had already undergone a previous T. cruzi infection screening-among which 81% were diagnosed in Catalonia and 19% in Bolivia. The prevalence of T. cruzi infection was 18.3% (with 3.3% of discordant results), the SARS-CoV-2 22.3% and the coinfection rate, 6%. The benefits of an integrated approach for COVID-19 and CD were shown, since it only took an average of 25% of additional time per patient and undoubtedly empowered the patients about the co-infection, its detection and care. Finally, the rapid diagnostic test used for COVID-19 showed a sensitivity of 89.5%. CONCLUSIONS: This research addresses CD and its co-infection, through an innovative way, an opportunity of systematic integration, during the COVID-19 pandemic.

Intra-Discrete Typing Unit TcV Genetic Variability of Trypanosoma cruzi in Chronic Chagas' Disease Bolivian Immigrant Patients in Barcelona, Spain.

Background: Trypanosoma cruzi has a high rate of biological and genetic variability, and its population structure is divided into seven distinct genetic groups (TcI-TcVI and Tcbat). Due to immigration, Chagas disease (ChD), caused by T. cruzi, has become a serious global health problem including in Europe. Therefore, the aim of this study was to evaluate the existence of genetic variability within discrete typing unit (DTU) TcV of T. cruzi in Bolivian patients with chronic ChD residing in Barcelona, Spain. Methods: The DNA was extracted from the peripheral blood of 27 patients infected with T. cruzi DTU TcV and the fragments of the genetic material were amplificated through the low stringency single primer-polymerase chain reaction (LSSP-PCR). The data generated after amplification were submitted to bioinformatics analysis. Results: Of the 27 patients evaluated in the study, 8/27 (29.6%) were male and 19/27 (70.4%) female, 17/27 (62.9%) were previously classified with the indeterminate clinical form of Chagas disease and 10/27 (37.1%) with Chagas cardiomyopathy. The LSSP-PCR detected 432 band fragments from 80 to 1,500 bp. The unweighted pair-group method analysis and principal coordinated analysis data demonstrated the existence of three distinct genetic groups with moderate-high rates of intraspecific genetic variability/diversity that had shared parasite's alleles in patients with the indeterminate and cardiomyopathy forms of ChD. Conclusions: This study demonstrated the existence of a moderate to high rate of intra-DTU TcV variability in T. cruzi. Certain alleles of the parasite were associated with the absence of clinical manifestations in patients harboring the indeterminate form of ChD. These results support the need to search for increasingly specific targets in the genome of T. cruzi to be correlated with its main biological properties and clinical features in patients with chronic ChD.

Quantification of parasite burden of Trypanosoma cruzi and identification of Discrete Typing Units (DTUs) in blood samples of Latin American immigrants residing in Barcelona, Spain.

BACKGROUND: Trypanosoma cruzi has a high genetic and biological diversity and has been subdivided into seven genetic lineages, named TcI-TcVI and TcBat. DTUs TcI-TcII-TcV and TcVI are agents of ChD in different regions of Latin America. Due to population movements, the disease is an emergent global public health problem. Thus, the aim of this study was to quantify the parasitic load and identify the presence of T. cruzi DTUs in 101 Latin American immigrants with chronic ChD, residing in Barcelona, Spain. METHODOLOGY / PRINCIPAL FINDINGS: 5ml of peripheral blood were collected in guanidine/EDTA from each patient for DNA extraction, quantification of the parasitic load and genotyping. A great variation of the parasitic load of the patients was verified: from 0.001 to 22.2 T. cruzi DNA (fg) / Blood DNA (ng). In patients from Bolivia the parasitic load was 3.76±4.43 T. cruzi DNA (fg) / Blood DNA (ng) (mean ± SD), in patients of other countries was 0.95±1.38 T. cruzi DNA (fg) / Blood DNA (ng). No statistically significant difference was observed in the parasitic load between patients with the indeterminate and cardiac forms of ChD (p = 0,57). Parasite genotyping was performed by multilocus conventional PCR. In patients from Bolivia there was a nearly equal prevalence of DTUs TcV (27/77), TcII/TcV/TcVI (26/77), and TcII/TcVI (22/77). TcVI was detected in only 2 samples (2/77). A higher prevalence of TcII/TcVI (19/24) was verified in patients of other countries, with low prevalence of TcII/TcV/TcVI (4/24) and TcV (1/24). CONCLUSIONS/SIGNIFICANCE: In this study, low/medium parasitic load was found in all patients evaluated. Our data corroborate previous conclusions indicating that patients from the Bolivia, living in Spain, are predominantly infected by TcV, and TcVI DTUs. On the other hand, in Non-Bolivians patients TcII/TcVI predominated. Surprisingly, in our cohort of 101 patients no infection by TcI DTU was observed.

A Community-Based Intervention for the Detection of Chagas Disease in Barcelona, Spain.

Chagas disease (CHD) has become a challenge in Spain due to the high prevalence of immigrants coming from endemic areas. One of the main difficulties for its control and elimination is its underdiagnosis. The identification and integral treatment of CHD are key to increasing rates of diagnosis, overcoming psycho-social barriers and avoiding CHD progression. Community interventions with in situ screening have proven to be a useful tool in detecting CHD among those with difficulties accessing health services. To determine the underdiagnosis rate of the population most susceptible to CHD among those attending two different Bolivian cultural events celebrated in Barcelona; to describe the sociodemographic characteristics of the people screened; and to analyse the results of the screening. The community interventions were carried out at two Bolivian cultural events held in Barcelona in 2017. Participants were recruited through community health agents. A questionnaire was given to determine the participants' prior knowledge of CHD. In situ screening was offered to those who had not previously been screened. Those who did not wish to be screened were asked for the reason behind their decision. Results were gathered in a database and statistical analyses were performed using STATA v14. 635 interviews were carried out. 95% of the subjects reported prior knowledge of CHD. 271 subjects were screened: 71.2% women and 28.8% men, of whom 87.8% were of Bolivian origin. The prevalence of CHD was 8.9%. Community health interventions with in situ screening are essential to facilitating access to diagnosis.

A retrospective study on the influence of siblings' relatedness in Bolivian patients with chronic Chagas disease.

BACKGROUND: Chagas disease is a protozoan infection caused by Trypanosoma cruzi. The disease has a chronic course in which 20-30% of the patients would develop progressive damage to the cardiovascular system and the gastrointestinal tube. We are still unable to predict who will develop end-organ damage but there are some acquired and genetic risk factors already known. RESULTS: We reviewed data from 833 patients with serologically confirmed Chagas disease in this retrospective study. Patients were classified as siblings or non-siblings (controls) and the results of pre-treatment blood PCR assay, end-organ damage (cardiac and/or gastrointestinal), and the presence of delayed type hypersensitivity (DTH) skin involvement in patients treated with benznidazole were analyzed. Siblings were grouped by family and we randomly generated groups of 2 or 3 persons with the remaining controls. We classified the results of each variable as concordant or discordant and compared the concordance in these results among the sibling groups with that among control groups. We identified 71 groups of siblings and randomly generated 299 groups of non-related patients. Pre-treatment blood PCR concordance was significantly higher (19%) among siblings compared to controls (P = 0.02), probably due to a higher frequency in pre-treatment positive results. No other statistically significant differences were found. CONCLUSIONS: A significant difference was found in the concordance of pre-treatment blood PCR for T. cruzi among siblings compared to non-related controls.

Imported strongyloidiasis: Data from 1245 cases registered in the +REDIVI Spanish Collaborative Network (2009-2017).

BACKGROUND: Imported strongyloidiasis is increasingly being diagnosed in non-endemic areas. The aim of this study was to describe the epidemiological, clinical and microbiological characteristics of patients with imported strongyloidiasis in Spain. METHODOLOGY: This is an observational retrospective study that included all patients diagnosed of strongyloidiasis registered in the +REDIVI Collaborative Network from 2009 to 2017. Demographic, epidemiological and clinical information was collected from the +REDIVI database, and extra information regarding microbiological techniques, treatment and follow-up was requested to participant centers. FINDINGS: Overall, 1245 cases were included. Most of them were immigrants (66.9%), and South America was the most frequent area of origin. Detection of larvae in stool samples was observed in 21.9% of the patients, and serological tests allowed making the diagnosis in the rest of the cases. Eosinophilia was present in 82.2% of cases. Treatment with ivermectin (compared with albendazole) was the most strongly associated factor to achieve the cure (OR 2.34). CONCLUSIONS: Given the long latency of the infection and the risk of developing a severe presentation, screening of S. stercoralis infection should be mandatory in patients coming from or had traveling to endemic areas, especially in those with immunosuppressant conditions.

First external quality assurance program for bloodstream Real-Time PCR monitoring of treatment response in clinical trials of Chagas disease.

Real-Time PCR (qPCR) testing is recommended as both a diagnostic and outcome measurement of etiological treatment in clinical practice and clinical trials of Chagas disease (CD), but no external quality assurance (EQA) program provides performance assessment of the assays in use. We implemented an EQA system to evaluate the performance of molecular biology laboratories involved in qPCR based follow-up in clinical trials of CD. An EQA program was devised for three clinical trials of CD: the E1224 (NCT01489228), a pro-drug of ravuconazole; the Sampling Study (NCT01678599), that used benznidazole, both conducted in Bolivia; and the CHAGASAZOL (NCT01162967), that tested posaconazole, conducted in Spain. Four proficiency testing panels containing negative controls and seronegative blood samples spiked with 1, 10 and 100 parasite equivalents (par. eq.)/mL of four Trypanosoma cruzi stocks, were sent from the Core Lab in Argentina to the participating laboratories located in Bolivia and Spain. Panels were analyzed simultaneously, blinded to sample allocation, at 4-month intervals. In addition, 302 random blood samples from both trials carried out in Bolivia were sent to Core Lab for retesting analysis. The analysis of proficiency testing panels gave 100% of accordance (within laboratory agreement) and concordance (between laboratory agreement) for all T. cruzi stocks at 100 par. eq./mL; whereas their values ranged from 71 to 100% and from 62 to 100% at 1 and 10 par. eq./mL, respectively, depending on the T. cruzi stock. The results obtained after twelve months of preparation confirmed the stability of blood samples in guanidine-EDTA buffer. No significant differences were found between qPCR results from Bolivian laboratory and Core Lab for retested clinical samples. This EQA program for qPCR analysis of CD patient samples may significantly contribute to ensuring the quality of laboratory data generated in clinical trials and molecular diagnostics laboratories of CD.

Seroprevalence of Strongyloides stercoralis infection among HTLV-I infected blood donors in Barcelona, Spain: A cross-sectional study.

Strongyloides stercoralis infection in patients with HTLV-I infection may lead to severe clinical manifestations. The aim of the present study is to determine the seroprevalence of S. stercoralis infection among blood donors who tested positive for HTLV-I infection. A cross-sectional study was performed at the Vall d'Hebron University Hospital (Barcelona, Spain) in 2016. Serum samples from HTLV-I positive patients diagnosed from 2008 to 2015 were retrieved from the Blood Bank, and S. stercoralis serology was performed. Thirty six serum samples from HTLV-I positive patients were retrieved from the Blood Bank. The blood samples came from 36 blood donors, and most of them were born in Latin America (75%), being Peru the most frequent country (11 participants). S. stercoralis serology was positive in one patient, corresponding to a prevalence of 2.8% (3.4% if we exclude donors coming from European countries, where the risk of S. stercoralis infection is highly unlikely).

Chikungunya virus infections among travellers returning to Spain, 2008 to 2014.

Since the first documented autochthonous transmission of chikungunya virus in the Caribbean island of Saint Martin in 2013, the infection has been reported within the Caribbean region as well as North, Central and South America. The risk of autochthonous transmission of chikungunya virus becoming established in Spain may be elevated due to the large numbers of travellers returning to Spain from countries affected by the 2013 epidemic in the Caribbean and South America, as well as the existence of the Aedes albopictus vector in certain parts of Spain. We retrospectively analysed the laboratory diagnostic database of the National Centre for Microbiology, Institute of Health Carlos III (CNM-ISCIII) from 2008 to 2014. During the study period, 264 confirmed cases, of 1,371 suspected cases, were diagnosed at the CNM-ISCIII. In 2014 alone, there were 234 confirmed cases. The highest number of confirmed cases were reported from the Dominican Republic (n = 136), Venezuela (n = 30) and Haiti (n = 11). Six cases were viraemic in areas of Spain where the vector is present. This report highlights the need for integrated active case and vector surveillance in Spain and other parts of Europe where chikungunya virus may be introduced by returning travellers.

Chagas Cardiomyopathy: Usefulness of EKG and Echocardiogram in a Non-Endemic Country.

BACKGROUND: Chagas disease (CD) is a major cause of cardiomyopathy in Latin America, and migration movements have now spread the disease worldwide. However, data regarding Chagas cardiomyopathy (CC) and the usefulness of echocardiography in non endemic countries are still scarce. METHODS AND RESULTS: We selected 485 patients in the chronic phase of CD from two Spanish settings. Data from physical examination, electrocardiogram (EKG), x-ray, and two dimensional transthoracic echocardiogram were recorded. Trypanosoma cruzi DNA was assessed by PCR in peripheral blood. Patients were stratified according to the Kuschnir classification and a combination of echocardiogram and electrocardiogram findings. Patients mainly came from Bolivia (459; 94.6%). One hundred and forty three patients (31.5%) had at least one electrocardiogram abnormality. Twenty seven patients (5.3%) had an abnormal echocardiography. Patients with abnormal echocardiography were older (47 (IQR 38-57) years vs 41 (IQR 38-57) years); p = 0.019) and there was a greater proportion of males (66.7% vs 29.7%); p<0.001). Among echocardiographic variables, diastolic dysfunction was associated with poor cardiac status. In the multivariate analysis, abnormal EKG and gender were associated with abnormal echocardiography. Echocardiography may be spared for males under 30 and females under 45 years old with normal EKG as the likelihood of having an abnormal echocardiography is minimal. Association between T. cruzi DNA in the peripheral blood and cardiac involvement was not observed. CONCLUSION: CC rates in the studied population are low. Age and sex are important determinants for the development of CC, and with the EKG should guide echocardiogram performance.

Imported cases of Chikungunya in Barcelona in relation to the current American outbreak.

BACKGROUND: The Chikungunya virus (CKIKV) is currently present in America. Travel between America and Europe is particularly intense and one of the main vectors of CHIKV, Aedes albopictus, is well established in the Mediterranean basin. We describe a series of imported cases that could originate a European outbreak. METHODS: We retrospectively studied cases of CHIKV originating in America and diagnosed in the last year in three Tropical Medicine Units of Barcelona of the International Health Program of the Catalan Health Institute (PROSICS). Clinical, microbiological and epidemiological data were analyzed. RESULTS: Forty-two CHIKV cases who had returned from 11 American countries were included. Fever was the most common symptom at onset (96.1%). Three months after symptom onset 50% continued with arthralgias, 35.3% fatigue and 11.8% arthritis. Three patients were viremic at the time of diagnosis by RT-PCR, and the remaining were diagnosed by serology (CHIKV IgM or IgG). Five (11.9%) patients had positive IgM for both dengue virus and CHIKV. CONCLUSIONS: The origin of the cases was diverse, the most frequent being initially the Dominican Republic, followed later by Venezuela and Colombia. Symptoms were not severe but persisted, accompanied by unremitting positive IgM. Diagnosis was mainly based on serology and RT-PCR, with the performance of the rapid immunochromatographic test being low. Phylogenetic studies showed that two viremic cases were caused by a strain of Asian lineage with a lower adaptability to Aedes albopictus. Co-infection with the dengue virus was common, but the clinical course was not affected by coinfection. Non-steroidal anti-inflammatory drugs were administered to 71.4% and steroids to 21.4%. The number of imported cases of CHIKV in Spain is rising due to introduction of this virus in America, and this could lead to an autochthonous outbreak if Public Health measures are not taken.

Concurrent Infection With Dengue Type 4 and Plasmodium falciparum Acquired in Haiti.

We report one laboratory-confirmed coinfection by dengue type 4 and Plasmodium falciparum imported to Spain from Haiti. Diagnosis was made by real-time polymerase chain reaction (RT-PCR), serology, quantitative buffy coat, and thick blood smear. In areas where both infections are present, diagnosis of both diseases should be considered because a delay in the treatment of malaria could be fatal.

Safety of liver transplantation with Chagas disease-seropositive donors for seronegative recipients.

The shortage of organs for transplantation has prompted the investigation of extended criteria donors, such as donors with transmissible infectious diseases. Here we report our recent experience with liver transplantation using organs from donors who were serologically positive for Chagas disease. We also provide a review of the literature and emphasize donor screening and preventive measures.