Evaluation and validation of a PrintrLab-based LAMP assay to identify Trypanosoma cruzi in newborns in Bolivia: a proof-of-concept study.

BACKGROUND: Vertical transmission of Trypanosoma cruzi represents approximately 20% of new Chagas disease cases. Early detection and treatment for women of childbearing age and newborns is a public health priority, but the lack of a simple and reliable diagnostic test remains a major barrier. We aimed to evaluate the performance of a point-of-care loop-mediated isothermal amplification (LAMP) assay for the detection of T cruzi. METHODS: In this proof-of-concept study, we coupled a low-cost 3D printer repurposed for sample preparation and amplification (PrintrLab) to the Eiken T cruzi-LAMP prototype to detect vertically transmitted T cruzi, which we compared with standardised PCR and with the gold-standard algorithm (microscopy at birth and 2 months and serological study several months later). We screened pregnant women from two hospitals in the Bolivian Gran Chaco province, and those who were seropositive for T cruzi were offered the opportunity for their newborns to be enrolled in the study. Newborns were tested by microscopy, LAMP, and PCR at birth and 2 months, and by serology at 8 months. FINDINGS: Between April 23 and Nov 17, 2018, 986 mothers were screened, among whom 276 were seropositive for T cruzi (28·0% prevalence, 95% CI 25·6-31·2). In total, 224 infants born to 221 seropositive mothers completed 8 months of follow-up. Congenital transmission was detected in nine of the 224 newborns (4·0% prevalence, 1·9-7·5) by direct microscopy observation, and 14 more cases were diagnosed serologically (6·3%, 3·6-10·3), accounting for an overall vertical transmission rate of 10·3% (6·6-15·0; 23 of 224). All microscopy-positive newborns were positive by PrintrLab-LAMP and by PCR, while these techniques respectively detected four and five extra positive cases among the remaining 215 microscopy-negative newborns. INTERPRETATION: The PrintrLab-LAMP yielded a higher sensitivity than microscopy-based analysis. Considering the simpler use and expected lower cost of LAMP compared with PCR, our findings encourage its evaluation in a larger study over a wider geographical area. FUNDING: Inter-American Development Bank.

Quantitative risk assessment for the introduction of bluetongue virus into mainland Europe by long-distance wind dispersal of Culicoides spp.: A case study from Sardinia.

Europe faces regular introductions and reintroductions of bluetongue virus (BTV) serotypes, most recently exemplified by the incursion of serotype 3 in the Netherlands. Although the long-distance wind dispersal of the disease vector, Culicoides spp., is recognized as a virus introduction pathway, it remains understudied in risk assessments. A Quantitative Risk Assessment framework was developed to estimate the risk of BTV-3 incursion into mainland Europe from Sardinia, where the virus has been present since 2018. We used an atmospheric transport model (HYbrid Single-Particle Lagrangian Integrated Trajectory) to infer the probability of airborne dispersion of the insect vector. Epidemiological disease parameters quantified the virus prevalence in vector population in Sardinia and its potential first transmission after introduction in a new area. When assuming a 24h maximal flight duration, the risk of BTV introduction from Sardinia is limited to the Mediterranean Basin, mainly affecting the southwestern area of the Italian Peninsula, Sicily, Malta, and Corsica. The risk extends to the northern and central parts of Italy, Balearic archipelago, and mainland France and Spain, mostly when maximal flight duration is longer than 24h. Additional knowledge on vector flight conditions and Obsoletus complex-specific parameters could improve the robustness of the model. Providing both spatial and temporal insights into BTV introduction risks, our framework is a key tool to guide global surveillance and preparedness against epizootics.

Parasitological, serological and molecular diagnosis of acute and chronic Chagas disease: from field to laboratory

There is no consensus on the diagnostic algorithms for many scenarios of Trypanosoma cruzi infection, which hinders the establishment of governmental guidelines in endemic and non-endemic countries. In the acute phase, parasitological methods are currently employed, and standardised surrogate molecular tests are being introduced to provide higher sensitivity and less operator-dependence. In the chronic phase, IgG-based serological assays are currently used, but if a single assay does not reach the required accuracy, PAHO/WHO recommends at least two immunological tests with different technical principles. Specific algorithms are applied to diagnose congenital infection, screen blood and organ donors or conduct epidemiological surveys. Detecting Chagas disease reactivation in immunosuppressed individuals is an area of increasing interest. Due to its neglect, enhancing access to diagnosis of patients at risk of suffering T. cruzi infection should be a priority at national and regional levels.

Executive Summary of the Consensus Statement of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), the Spanish Society of Tropical Medicine and International Health (SEMTSI), the Spanish Association of Surgeons (AEC), the Spanish Society of Pneumology and Thoracic Surgery (SEPAR), the Spanish Society of Thoracic Surgery (SECT), the Spanish Society of Vascular and Interventional Radiology (SERVEI), and the Spanish Society of Paediatric Infectious Diseases (SEIP), on the Management of Cystic Echinococcosis / Resumen ejecutivo de la Declaración de consenso de la Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica (SEIMC), la Sociedad Española de Medicina Tropical y Salud Internacional (SEMTSI), la Asociación Española de Cirujanos (AEC), la Sociedad Española de Neumología y Cirugía Torácica (SEPAR), la Sociedad Española de Cirugía Torácica (SECT), la Sociedad Española de Radiología Vascular e Intervencionista (SERVEI) y la Sociedad Española de Infectología Pediátrica (SEIP) sobre el tratamiento de la equinococosis quística

The Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), the Spanish Society of Tropical Medicine and International Health (SEMTSI), the Spanish Association of Surgeons (AEC), the Spanish Society of Pneumology and Thoracic Surgery (SEPAR), the Spanish Society of Thoracic Surgery (SECT), the Spanish Society of Vascular and Interventional Radiology (SERVEI), and the Spanish Society of Paediatric Infectious Diseases (SEIP) considered it pertinent to issue a consensus statement on the management of cystic echinococcosis (CE) to guide healthcare professionals in the care of patients with CE. Specialists from several fields (clinicians, surgeons, radiologists, microbiologists, and parasitologists) identified the most clinically relevant questions and developed this Consensus Statement, evaluating the available evidence-based data to propose a series of recommendations on the management of this disease. This Consensus Statement is accompanied by the corresponding references on which these recommendations are based. Prior to publication, the manuscript was open for comments and suggestions from the members of the SEIMC and the scientific committees and boards of the various societies involved

La Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica (SEIMC), la Sociedad Española de Medicina Tropical y Salud Internacional (SEMTSI), la Asociación Española de Cirujanos (AEC), la Sociedad Española de Neumología y Cirugía Torácica (SEPAR), la Sociedad Española de Cirugía Torácica (SECT), la Sociedad Española de Radiología Vascular e Intervencionista (SERVEI) y la Sociedad Española de Infectología Pediátrica (SEIP) han considerado pertinente la elaboración de una declaración de consenso sobre el tratamiento de la equinococosis quística (EQ) que sirva de ayuda al personal sanitario en la atención de pacientes con EQ. Varios tipos de profesionales (médicos, cirujanos, radiólogos, microbiólogos y parasitólogos) han seleccionado las preguntas más clínicamente relevantes y han desarrollado esta Declaración de consenso, en la que evalúan los datos basados en la evidencia disponibles para proponer una serie de recomendaciones sobre el tratamiento de esta enfermedad. Esta Declaración de consenso se acompaña de la bibliografía correspondiente que fundamenta estas recomendaciones. Antes de su publicación, el manuscrito estuvo abierto a comentarios y sugerencias de los miembros de la SEIMC y de los comités científicos y juntas directivas de las diferentes sociedades implicadas

Effect of untreated bed nets on blood-fed Phlebotomus argentipes in kala-azar endemic foci in Nepal and India

Observational studies in the Indian subcontinent have shown that untreated nets may be protective against visceral leishmaniasis (VL). In this study, we evaluated the effect of untreated nets on the blood feeding rates of Phlebotomus argentipes as well as the human blood index (HBI) in VL endemic villages in India and Nepal. The study had a "before and after intervention" design in 58 households in six clusters. The use of untreated nets reduced the blood feeding rate by 85 percent (95 percent CI 76.5-91.1 percent) and the HBI by 42.2 percent (95 percent CI 11.1-62.5 percent). These results provide circumstantial evidence that untreated nets may provide some degree of personal protection against sand fly bites.

Evaluación de las consecuencias de una epidemia de fiebre aftosa para el sector bovino en España / An evaluation of the consequences of a foot and mouth epidemic for the Spanish bovine industry

Este estudio evalúa el riesgo de introducción de la fiebre aftosa (FA) en España y las consecuencias de una epidemia para el sector bovino. El riesgo medio de introducción de la FA en España es de 0,079 por año. Andalucía y Cataluña son las comunidades con mayor probabilidad de aparición de un foco primario. Para determinar la difusión de la epidemia, se han simulado tres escenarios en función de su dispersión geográfica. El número medio de granjas de bovinos sacrificadas sería de entre 90 y 509 (con una población total de entre 10.500 y 45.400 animales). El número medio de explotaciones inmovilizadas oscilaría entre 1.103 y 4.477 con un censo de 28.000 y 185.500 bovinos respectivamente. Los resultados de este estudio han sido empleados para determinar la viabilidad y el costo de la inclusión de la FA en un seguro agrario (AU)

In this paper we evaluate both the risk of Foot-and-Mouth disease introduction into Spain and the consequences of an epidemic for the cattle industry. The mean risk of FMD introduction into Spain is 0,079 per year. Andalusia and Catalonia are the regions with the highest risk of a primary outbreak appearance. In order to determine the spread of the epidemic, we have simulated three likely scenarios according to the geographic distribution. The mean number of stamping out herds would be between 90 and 509 (with a cattle population between 10.500 and 45.400 bovines). The mean number of herds affected by the stand-still of livestock transport varies between 1.103 and 4.477 with a census of 28.000 and 185.500 bovines respectively. The results of this study are used by an agricultural insurance company to determine the feasibility and the cost of the inclusion of FMD insurance in their products (AU)