23 research outputs found
Persistence of Zika virus in semen 93 days after the onset of symptoms
INTRODUCTION: Zika virus is mainly transmitted through the bites
of infected Aedes mosquitoes, although mother-to-child and
sexual transmission have also been described. The presence of
Zika virus in semen after infection seems to be not uncommon,
but the duration of viral persistence has not been
well-determined. METHODS: Molecular, serological and cell
culture methods were used for the diagnosis and follow up of a
case of Zika virus infection imported from Venezuela. Serial
samples of serum, urine and semen were analyzed to investigate
the persistence of the Zika virus. RESULTS: Zika virus was
detected in semen samples up to 93 days after the onset of
symptoms. CONCLUSIONS: Our results confirm the persistence of
Zika virus in semen samples for long periods after infection
Immunosuppression and Chagas disease: a management challenge
Immunosuppression, which has become an increasingly relevant clinical condition in the last 50 years, modifies the natural history of Trypanosoma cruzi infection in most patients with Chagas disease. The main goal in this setting is to prevent the consequences of reactivation of T. cruzi infection by close monitoring. We analyze the relationship between Chagas disease and three immunosuppressant conditions, including a description of clinical cases seen at our center, a brief review of the literature, and recommendations for the management of these patients based on our experience and on the data in the literature. T. cruzi infection is considered an opportunistic parasitic infection indicative of AIDS, and clinical manifestations of reactivation are more severe than in acute Chagas disease. Parasitemia is the most important defining feature of reactivation. Treatment with benznidazole and/or nifurtimox is strongly recommended in such cases. It seems reasonable to administer trypanocidal treatment only to asymptomatic immunosuppressed patients with detectable parasitemia, and/or patients with clinically defined reactivation. Specific treatment for Chagas disease does not appear to be related to a higher incidence of neoplasms, and a direct role of T. cruzi in the etiology of neoplastic disease has not been confirmed. Systemic immunosuppressive diseases or immunosuppressants can modify the natural course of T. cruzi infection. Immunosuppressive doses of corticosteroids have not been associated with higher rates of reactivation of Chagas disease. Despite a lack of evidence-based data, treatment with benznidazole or nifurtimox should be initiated before immunosuppression where possible to reduce the risk of reactivation. Timely antiparasitic treatment with benznidazole and nifurtimox (or with posaconazole in cases of therapeutic failure) has proven to be highly effective in preventing Chagas disease reactivation, even if such treatment has not been formally incorporated into management protocols for immunosuppressed patients. International consensus guidelines based on expert opinion would greatly contribute to standardizing the management of immunosuppressed patients with Chagas disease
First field and laboratory evaluation of LAMP assay for malaria diagnosis in Cubal, Angola
Angola; MalariaAngola; MalariaAngola; MalàriaBackground
Malaria is a globally distributed infectious disease. According to the World Health Organization, Angola is one of the six countries that account for over half the global malaria burden in terms of both malaria cases and deaths. Diagnosis of malaria still depends on microscopic examination of thin and thick blood smears and rapid diagnostic tests (RDTs), which often lack analytical and clinical sensitivity. Molecular methods could overcome these disadvantages. The aim of this study was to evaluate, for the first time to our knowledge, the performance of a loop-mediated isothermal amplification (LAMP) for the diagnosis of malaria in an endemic area in Cubal, Angola, and to assess the reproducibility at a reference laboratory.
Methods
A total of 200 blood samples from patients attended at Hospital Nossa Senhora da Paz, Cubal, Angola, were analysed for Plasmodium spp. detection by microscopy, RDTs, and LAMP. LAMP assay was easily performed in a portable heating block, and the results were visualized by a simple colour change. Subsequently, the samples were sent to a reference laboratory in Spain to be reanalysed by the same colorimetric LAMP assay and also in real-time LAMP format.
Results
In field tests, a total of 67/200 (33.5%) blood samples were microscopy-positive for Plasmodium spp., 98/200 RDT positive, and 112/200 (56%) LAMP positive. Using microscopy as reference standard, field LAMP detected more microscopy-positive samples than RDTs (66/67; 98% vs. 62/67; 92.5%). When samples were reanalysed at a reference laboratory in Spain using both colorimetric and real-time assays, the overall reproducibility achieved 84.5%.
Conclusions
This is the first study to our knowledge in which LAMP has been clinically evaluated on blood samples in a resource-poor malaria-endemic area. The colorimetric LAMP proved to be more sensitive than microscopy and RDTs for malaria diagnosis in field conditions. Furthermore, LAMP showed an acceptable level of reproducibility in a reference laboratory. The possibility to use LAMP in a real-time format in a portable device reinforces the reliability of the assay for molecular diagnosis of malaria in resource-poor laboratories in endemic areas.The work was supported by the Institute of Health Carlos III, ISCIII, Spain (www.isciii.es) grant number PI22/01721 (PFS), European Union cofinancing by FEDER (Fondo Europeo de Desarrollo Regional) ‘Una manera de hacer Europa’. We also acknowledge support by the Predoctoral Fellowship Program of Junta de Castilla y León cofounded by Fondo Social Europeo: (BDNS Identif.: 422058, BFS) and (BDNS Identif: 487971, BCV)
First field and laboratory evaluation of LAMP assay for malaria diagnosis in Cubal, Angola
[EN]Malaria is a globally distributed infectious disease. According to the World Health Organization, Angola is one of the six countries that account for over half the global malaria burden in terms of both malaria cases and deaths. Diagnosis of malaria still depends on microscopic examination of thin and thick blood smears and rapid diagnostic tests (RDTs), which often lack analytical and clinical sensitivity. Molecular methods could overcome these disadvantages. The aim of this study was to evaluate, for the first time to our knowledge, the performance of a loop-mediated isothermal amplification (LAMP) for the diagnosis of malaria in an endemic area in Cubal, Angola, and to assess the reproducibility at a reference laboratory
Analytical Evaluation of Dried Blood Spot and Rapid Diagnostic Test as a New Strategy for Serological Community Screening for Chronic Chagas Disease
Trypanosoma cruzi; Mancha de sangre seca (DBS); Cribado serológicoTrypanosoma cruzi; Taca de sang seca (DBS); Cribratge serològicTrypanosoma cruzi; Dried blood spot (DBS); Serological screeningBackground: Chagas disease is a public health problem not only in Latin America, but also in other regions, including Spain, due to migration movements. Conventional serological diagnosis requires an invasive sample (plasma or serum) and a well-equipped laboratory. To circumvent those limitations, blood samples dried on filter paper (DBS) or Rapid Diagnostic Test (RDT) could be a practical alternative to reference protocol for serological screening in epidemiological studies. We evaluated the usefulness of dried blood sampling and a rapid diagnostic test (Trypanosoma Detect™) for the detection of antibodies against T. cruzi for their use in community-based screening.
Methodology/Principal Findings: A total of 162 stored paired whole-blood and serum samples from Latin American migrants and 25 negative-control blood samples were included. Diagnosis of chronic Chagas disease was performed in serum according to WHO algorithms. Blood samples were retrospectively collected as dried spots and then analyzed using two different serological techniques, enzyme-linked immunosorbent assay (ELISA) and electrochemiluminescence immunoassay (E-CLIA). Whole-blood samples were also used to evaluate a rapid diagnostic test based on immunochromatography. A better correlation with conventional serum was observed in dried blood elutes using E-CLIA than ELISA (97% vs. 77% sensitivity, respectively). Both assays reported 100% specificity. The median cut-off index values of E-CLIA for dried blood were significantly lower than those for serum (138.1 vs. 243.3, P<0.05). The Trypanosoma Detect™ test presented a sensitivity and specificity of 89.6% and 100%, respectively.
Conclusions: The detection of antibodies against T. cruzi in dried blood samples shows a higher sensitivity when using E-CLIA compared with ELISA. Trypanosoma Detect™ is easier to use but has a lower sensitivity. Hence, we propose a sequential strategy based on performing the rapid test first, and a negative result will be confirmed by DBS-ECLIA for use in community Chagas disease screening programs.This work has been supported by the Fundació la Marató TV3 (project number 20182610)
Opportunistic Community Screening of Chronic Chagas Disease Using a Rapid Diagnosis Test in Pharmacies in Barcelona (Catalonia, Spain): Study Protocol and Pilot Phase Results
Chagas disease; Community pharmacies; Rapid testEnfermedad de Chagas; Farmacias comunitarias; Test rapidoMalaltia de Chagas; Farmàcies comunitàries; Prova ràpidaObjectives: This study aimed to report the protocol and results from the pilot phase of an opportunistic CP-based CD screening program in Barcelona, Spain.
Methods: Three strategies according to recruitment approach were designed: passive, active and active-community. The study process consisted of signing the informed consent form, recording the patient’s data in a web-based database system, and performing the rapid test and blood collection on dry paper.
Results: Nineteen pharmacies participated and 64 patients were included during the pilot phase of the study. The rapid diagnostic test (RDT) was positive in 2/64 (3.13%) cases. Of the 49 DBS samples that arrived at the laboratory, 22 (45%) were collected incorrectly. After quantitative and qualitative assessment of the program, the dry paper sample and passive strategy were ruled out.
Conclusion: DBS sampling and the passive strategy are not suitable for CD screening in community pharmacies. There is a need to expand the number of participating pharmacies and individuals to determine whether conducting a RDT in community pharmacies is an effective screening method to increase access to CD diagnosis in a non-endemic area.This work has been supported by the Fundació la Marató TV3 (project number 481/U/2018)
Epidemiological and clinical trends of imported strongyloidiasis in a referral international health unit, Barcelona, Spain: A 12-year period experience
Screening; Strongyloides stercoralis; StrongyloidiasisCribado; Strongyloides stercoralis; EstrongiloidiasisCribratge; Strongyloides stercoralis; EstrogiloidiasiBackground
Imported strongyloidiasis in non-endemic countries has increasingly been diagnosed. The aim of the present study is to describe the main epidemiological and clinical characteristics of patients with imported strongyloidiasis attended in a referral International Health Unit and to detect trend changes over a 12-year period.
Methods
This is an observational retrospective study including all imported strongyloidiasis cases seen at the International Health Unit Vall d’Hebron-Drassanes (Barcelona, Spain) from January 2009 to December 2020. Epidemiological and clinical characteristics from included patients were collected.
Results
Overall, 865 cases of imported strongyloidiasis were diagnosed, of whom 472 (54.6 %) were men and mean age was 38.7 (SD 13.4) years. Most cases were diagnosed in migrants (830, 96 %). The distribution of the geographic origin was: Latin America (561, 67.6 %), Sub-Saharan Africa (148, 17.8 %), Asia (113, 13.6 %), North Africa (5, 0.6 %), Eastern Europe (2, 0.2 %), and North America (1, 0.1 %). The main reasons for consultation at the Unit were screening of health status (371, 42.9 %), laboratory test alteration (367, 42.4 %), gastrointestinal symptoms (56, 6.5 %), cutaneous symptoms (26, 3 %), and other clinical symptoms (45, 5.2 %). An increase in the number of cases was observed in the last years of the study period.
Conclusions
Imported strongyloidiasis has increasingly been diagnosed in our referral unit, mostly due to screening strategies implementation. Most of the patients were young migrants coming from Latin America, with no symptoms at the time of diagnosis. The optimization of screening strategies will increase the detection and treatment of cases, reducing potential complications
Usefulness of real-time PCR for urogenital schistosomiasis diagnosis in preschool children in a high-prevalence area in Angola
Urogenital schistosomiasis; Diagnosis; AngolaDiagnòstic; Esquistosomiasi urogenital; AngolaDiagnóstico; Esquistosomiasis urogenital; AngolaBackground
Urogenital schistosomiasis caused by Schistosoma haematobium is highly endemic in the municipality of Cubal in Angola. Currently, diagnosis is based on the observation of S. haematobium eggs in urine samples by microscopy but this method has low sensitivity. Few studies have been performed using molecular techniques in high-prevalence areas for the detection of S. haematobium. The objective of this study is to evaluate the usefulness of real-time PCR as a diagnostic technique for urogenital schistosomiasis among preschool-age children and its correlation with morbidity data.
Methods
A cross-sectional study was conducted in Cubal, Angola, involving 97 urine samples from preschool-age children analyzed by the dipstick test, microscopic examination of filtered urine, and real-time PCR. The diagnosis of urogenital schistosomiasis was based on microscopy and/or real-time PCR results. Clinical and ultrasonography evaluation was performed to rule out complications of schistosomiasis.
Results
We detected a total of 64.95% of samples positive by real-time PCR and 37.11% by microscopy. The sensitivity of parasitological diagnosis of urogenital schistosomiasis by real-time PCR and microscopy was 95.45% and 54.55%, respectively, and the sensitivity of real-time PCR compared with microscopy was 91.67%. A positive real-time PCR result was significantly related to older age (mean = 3.22 years), detection of eggs by microscopy, and abnormal urine dipstick results (18.56% with proteinuria, 31.96% with leukocyturia, and 31.96% with microhematuria) (p-value<0.05). Ultrasound analysis showed that 23.94% of children had urinary tract abnormalities, and it was significantly related to the real-time PCR diagnosis (p-value<0.05).
Conclusions
Real-time PCR is a more sensitive technique than microscopy for urinary schistosomiasis diagnosis in preschool-age children in Cubal. This increase in sensitivity would allow earlier diagnosis and treatment, thus reducing the morbidity associated with schistosomiasis in its early stages
Unexpected Loa loa Finding in an Asymptomatic Patient From The Gambia: A Case Report
Gambia; Epidemiology; LoiasisGambia; Epidemiología; LoiasisGàmbia; Epidemiologia; LoiasiA 17-year-old asymptomatic male from The Gambia presented for a routine health examination after migration to Spain. Laboratory diagnosis confirmed the presence of Loa loa microfilariae. This unusual finding emphasizes the importance of screening in newly arrived migrants and the need of an extended anamnesis including migratory route and previous travels
COVID-19 Clinical Profile in Latin American Migrants Living in Spain: Does the Geographical Origin Matter?
COVID-19; Latin America; SeverityCOVID-19; Amèrica Llatina; GravetatCOVID-19; América Latina; GravedadThe aim of this study was to describe and compare the clinical characteristics of hospitalized patients with COVID-19 pneumonia according to their geographical origin. This is a retrospective case-control study of hospitalized patients with confirmed COVID-19 pneumonia treated at Vall d’Hebron University Hospital (Barcelona) during the first wave of the pandemic. Cases were defined as patients born in Latin America and controls were randomly selected among Spanish patients matched by age and gender. Demographic and clinical variables were collected, including comorbidities, symptoms, vital signs and analytical parameters, intensive care unit admission and outcome at 28 days after admission. Overall, 1080 hospitalized patients were registered: 774 (71.6%) from Spain, 142 (13.1%) from Latin America and the rest from other countries. Patients from Latin America were considered as cases and 558 Spanish patients were randomly selected as controls. Latin American patients had a higher proportion of anosmia, rhinorrhea and odynophagia, as well as higher mean levels of platelets and lower mean levels of ferritin than Spanish patients. No differences were found in oxygen requirement and mortality at 28 days after admission, but there was a higher proportion of ICU admissions (28.2% vs. 20.2%, p = 0.0310). An increased proportion of ICU admissions were found in patients from Latin America compared with native Spanish patients when adjusted by age and gender, with no significant differences in in-hospital mortality.Isabel Campos-Varela’s research activity is funded by grant PI19/00330 from Instituto de Salud Carlos III. CIBERehd is supported by Instituto de Salud Carlos III. The work was independent of all funding. This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors