Using image segmentation models to analyse high-resolution earth observation data: new tools to monitor disease risks in changing environments.

BACKGROUND: In the near future, the incidence of mosquito-borne diseases may expand to new sites due to changes in temperature and rainfall patterns caused by climate change. Therefore, there is a need to use recent technological advances to improve vector surveillance methodologies. Unoccupied Aerial Vehicles (UAVs), often called drones, have been used to collect high-resolution imagery to map detailed information on mosquito habitats and direct control measures to specific areas. Supervised classification approaches have been largely used to automatically detect vector habitats. However, manual data labelling for model training limits their use for rapid responses. Open-source foundation models such as the Meta AI Segment Anything Model (SAM) can facilitate the manual digitalization of high-resolution images. This pre-trained model can assist in extracting features of interest in a diverse range of images. Here, we evaluated the performance of SAM through the Samgeo package, a Python-based wrapper for geospatial data, as it has not been applied to analyse remote sensing images for epidemiological studies. RESULTS: We tested the identification of two land cover classes of interest: water bodies and human settlements, using different UAV acquired imagery across five malaria-endemic areas in Africa, South America, and Southeast Asia. We employed manually placed point prompts and text prompts associated with specific classes of interest to guide the image segmentation and assessed the performance in the different geographic contexts. An average Dice coefficient value of 0.67 was obtained for buildings segmentation and 0.73 for water bodies using point prompts. Regarding the use of text prompts, the highest Dice coefficient value reached 0.72 for buildings and 0.70 for water bodies. Nevertheless, the performance was closely dependent on each object, landscape characteristics and selected words, resulting in varying performance. CONCLUSIONS: Recent models such as SAM can potentially assist manual digitalization of imagery by vector control programs, quickly identifying key features when surveying an area of interest. However, accurate segmentation still requires user-provided manual prompts and corrections to obtain precise segmentation. Further evaluations are necessary, especially for applications in rural areas.

Íleo biliar complicado con infección con SARS-CoV-2. Reporte de caso

Introducción: El Íleo biliar (IB) es una obstrucción intestinal mecánica muy poco frecuente, del 1 al 4 % de todas las obstrucciones intestinales, y es más común en pacientes de edad avanzada. Se produce a través de una fístula bilioentérica en el intestino delgado, sobre todo en el íleon distal. Luego de tener un enfoque diagnóstico mediante imagenología, en su gran mayoría, se opta por el tratamiento quirúrgico para eliminar el o los cálculos impactados. El éxito de esta intervención depende en gran medida del tamaño del cálculo biliar, de la ubicación de la obstrucción intestinal y comorbilidades preexistentes. Caso clínico: Mujer de 78 años con cuadro clínico de obstrucción intestinal, emesis de contenido fecaloide y sintomática respiratoria; se evidenció una masa concéntrica a nivel de íleon distal y proceso neumónico concomitante por tomografía toracoabdominal. Se realizó laparotomía exploratoria con enterolitotomía, extracción de cálculo y anastomosis íleo-ileal y fue trasladada a la UCI en donde presentó falla ventilatoria y requerimiento de ventilación mecánica; se confirmó infección viral por SARS-CoV-2 mediante RT - PCR. Discusión: El IB es una obstrucción intestinal que ocurre con mayor frecuencia en pacientes de edad avanzada. Se habla de la fisiopatología y mecanismo de producción de la fístula entérica y se presentan opciones diagnósticas, terapéuticas y quirúrgicas para dirigir el manejo clínico más apropiado. Conclusión: El IB es difícil de diagnosticar. Debido a su baja incidencia, no existe un consenso que paute el manejo a seguir en los pacientes con diagnóstico de IB. Aunque el tratamiento estándar es la intervención quirúrgica, hay diversas opiniones en cuanto al tipo de cirugía a realizar.

Introduction: Biliary ileus (BI) is a very rare mechanical intestinal obstruction, responsible for 1-4% of all intestinal obstructions and more frequent in elderly patients. It occurs through a bilioenteric fistula in the small bowel, mainly in the distal ileum. After a diagnostic imaging approach, the vast majority opt for surgical treatment to remove the impacted stone or stones. The success of this intervention depends largely on the size of the stone, the location of the bowel obstruction and pre-existing comorbidities. Case report: 78-year-old woman with clinical symptoms of intestinal obstruction, fecaloid emesis, respiratory symptoms, concentric mass at the level of the distal ileum and concomitant pneumonic process in the thoraco-abdominal CT scan. Exploratory laparotomy was performed, with total lithotomy, extraction of the calculus and ileo-ileal anastomosis, and she was transferred to the ICU, where she presented ventilatory failure and required mechanical ventilation. SARS-CoV-2 infection was confirmed with RT-PCR. Discussion: IB is an intestinal obstruction that occurs more frequently in elderly patients. The pathophysiology and the mechanism of production of enteric fistula are discussed and diagnostic, therapeutic and surgical options are presented to guide the most appropriate clinical management. Conclusion: Enteric fistula is difficult to diagnose. Due to its low incidence, there is no consensus on the management of patients diagnosed with IB. Although the standard treatment is surgical intervention, there are divergent opinions as to the type of surgery to be performed.

Mapping Malaria Vector Habitats in West Africa: Drone Imagery and Deep Learning Analysis for Targeted Vector Surveillance.

Disease control programs are needed to identify the breeding sites of mosquitoes, which transmit malaria and other diseases, in order to target interventions and identify environmental risk factors. The increasing availability of very-high-resolution drone data provides new opportunities to find and characterize these vector breeding sites. Within this study, drone images from two malaria-endemic regions in Burkina Faso and Côte d'Ivoire were assembled and labeled using open-source tools. We developed and applied a workflow using region-of-interest-based and deep learning methods to identify land cover types associated with vector breeding sites from very-high-resolution natural color imagery. Analysis methods were assessed using cross-validation and achieved maximum Dice coefficients of 0.68 and 0.75 for vegetated and non-vegetated water bodies, respectively. This classifier consistently identified the presence of other land cover types associated with the breeding sites, obtaining Dice coefficients of 0.88 for tillage and crops, 0.87 for buildings and 0.71 for roads. This study establishes a framework for developing deep learning approaches to identify vector breeding sites and highlights the need to evaluate how results will be used by control programs.

The use of drones for mosquito surveillance and control.

In recent years, global health security has been threatened by the geographical expansion of vector-borne infectious diseases such as malaria, dengue, yellow fever, Zika and chikungunya. For a range of these vector-borne diseases, an increase in residual (exophagic) transmission together with ecological heterogeneity in everything from weather to local human migration and housing to mosquito species' behaviours presents many challenges to effective mosquito control. The novel use of drones (or uncrewed aerial vehicles) may play a major role in the success of mosquito surveillance and control programmes in the coming decades since the global landscape of mosquito-borne diseases and disease dynamics fluctuates frequently and there could be serious public health consequences if the issues of insecticide resistance and outdoor transmission are not adequately addressed. For controlling both aquatic and adult stages, for several years now remote sensing data have been used together with predictive modelling for risk, incidence and detection of transmission hot spots and landscape profiles in relation to mosquito-borne pathogens. The field of drone-based remote sensing is under continuous change due to new technology development, operation regulations and innovative applications. In this review we outline the opportunities and challenges for integrating drones into vector surveillance (i.e. identification of breeding sites or mapping micro-environmental composition) and control strategies (i.e. applying larval source management activities or deploying genetically modified agents) across the mosquito life-cycle. We present a five-step systematic environmental mapping strategy that we recommend be undertaken in locations where a drone is expected to be used, outline the key considerations for incorporating drone or other Earth Observation data into vector surveillance and provide two case studies of the advantages of using drones equipped with multispectral cameras. In conclusion, recent developments mean that drones can be effective for accurately conducting surveillance, assessing habitat suitability for larval and/or adult mosquitoes and implementing interventions. In addition, we briefly discuss the need to consider permissions, costs, safety/privacy perceptions and community acceptance for deploying drone activities.

Quantifying the effect of human population mobility on malaria risk in the Peruvian Amazon.

The impact of human population movement (HPM) on the epidemiology of vector-borne diseases, such as malaria, has been described. However, there are limited data on the use of new technologies for the study of HPM in endemic areas with difficult access such as the Amazon. In this study conducted in rural Peruvian Amazon, we used self-reported travel surveys and GPS trackers coupled with a Bayesian spatial model to quantify the role of HPM on malaria risk. By using a densely sampled population cohort, this study highlighted the elevated malaria transmission in a riverine community of the Peruvian Amazon. We also found that the high connectivity between Amazon communities for reasons such as work, trading or family plausibly sustains such transmission levels. Finally, by using multiple human mobility metrics including GPS trackers, and adapted causal inference methods we identified for the first time the effect of human mobility patterns on malaria risk in rural Peruvian Amazon. This study provides evidence of the causal effect of HPM on malaria that may help to adapt current malaria control programmes in the Amazon.

Perceptions of self-medication of the population, during the covid-19 pandemic in Peru / Percepciones de automedicación de la población durante la pandemia covid-19 en Perú

Background: Describe characteristics of self-medication of the population, in the context of the COVID 19 pandemic. Material and Methods: We carried out a cross-sectional survey with students in a major public Peruvian university. We measured perception of self-medication of the population, as well as characteristics, consequences, and associated factors. Results: A total of 274 students of Pharmacy and biochemistry filled in the questionnaire, 80.3% of which reported to know someone that self-medicated during the COVID-19 pandemic. 98.9 % of surveyed participants considered that the current pandemic increased self-medication practices in the population and that it occurred more frequently when people have symptoms associated with COVID-19 (65.4%). The medicines most frequently used were ivermectin (79.2%), azithromycin (71.2%) and hydroxychloroquine (38.7%). Conclusion: According to the surveyed participants, self-medication has increased in the general population during the COVID-19 pandemic. Strategies to prevent these practices are needed, as they could delay adequate medical care.

Introducción: Describir las características de la automedicación de la población, en el contexto de la pandemia de COVID 19. Material y Metodos: Realizamos una encuesta transversal con estudiantes de una importante universidad pública peruana. Se midió la percepción de la automedicación de la población, así como características, consecuencias y factores asociados. Resultados: Completaron el cuestionario un total de 274 estudiantes de Farmacia y Bioquímica, de los cuales el 80,3% refirió conocer a alguien que se automedicó durante la pandemia de COVID-19. El 98,9% de los encuestados consideró que la pandemia actual aumentó las prácticas de automedicación en la población y que se presentó con mayor frecuencia cuando las personas presentan síntomas asociados al COVID-19 (65,4%). Los medicamentos más utilizados fueron ivermectina (79,2%), azitromicina (71,2%) e hidroxicloroquina (38,7%). Conclusión: Según los participantes encuestados, la automedicación ha aumentado en la población general durante la pandemia de COVID-19. Se necesitan estrategias para prevenir estas prácticas, ya que podrían retrasar la atención médica adecuada.

Technical Workflow Development for Integrating Drone Surveys and Entomological Sampling to Characterise Aquatic Larval Habitats of Anopheles funestus in Agricultural Landscapes in Côte d'Ivoire.

Land-use practices such as agriculture can impact mosquito vector breeding ecology, resulting in changes in disease transmission. The typical breeding habitats of Africa's second most important malaria vector Anopheles funestus are large, semipermanent water bodies, which make them potential candidates for targeted larval source management. This is a technical workflow for the integration of drone surveys and mosquito larval sampling, designed for a case study aiming to characterise An. funestus breeding sites near two villages in an agricultural setting in Côte d'Ivoire. Using satellite remote sensing data, we developed an environmentally and spatially representative sampling frame and conducted paired mosquito larvae and drone mapping surveys from June to August 2021. To categorise the drone imagery, we also developed a land cover classification scheme with classes relative to An. funestus breeding ecology. We sampled 189 potential breeding habitats, of which 119 (63%) were positive for the Anopheles genus and nine (4.8%) were positive for An. funestus. We mapped 30.42 km2 of the region of interest including all water bodies which were sampled for larvae. These data can be used to inform targeted vector control efforts, although its generalisability over a large region is limited by the fine-scale nature of this study area. This paper develops protocols for integrating drone surveys and statistically rigorous entomological sampling, which can be adjusted to collect data on vector breeding habitats in other ecological contexts. Further research using data collected in this study can enable the development of deep-learning algorithms for identifying An. funestus breeding habitats across rural agricultural landscapes in Côte d'Ivoire and the analysis of risk factors for these sites.

Open-Source 3D Printable GPS Tracker to Characterize the Role of Human Population Movement on Malaria Epidemiology in River Networks: A Proof-of-Concept Study in the Peruvian Amazon.

Human movement affects malaria epidemiology at multiple geographical levels; however, few studies measure the role of human movement in the Amazon Region due to the challenging conditions and cost of movement tracking technologies. We developed an open-source low-cost 3D printable GPS-tracker and used this technology in a cohort study to characterize the role of human population movement in malaria epidemiology in a rural riverine village in the Peruvian Amazon. In this pilot study of 20 participants (mean age = 40 years old), 45,980 GPS coordinates were recorded over 1 month. Characteristic movement patterns were observed relative to the infection status and occupation of the participants. Applying two analytical animal movement ecology methods, utilization distributions (UDs) and integrated step selection functions (iSSF), we showed contrasting environmental selection and space use patterns according to infection status. These data suggested an important role of human movement in the epidemiology of malaria in the Peruvian Amazon due to high connectivity between villages of the same riverine network, suggesting limitations of current community-based control strategies. We additionally demonstrate the utility of this low-cost technology with movement ecology analysis to characterize human movement in resource-poor environments.

Travel Time to Health Facilities as a Marker of Geographical Accessibility Across Heterogeneous Land Coverage in Peru.

To better estimate the travel time to the most proximate health care facility (HCF) and determine differences across heterogeneous land coverage types, this study explored the use of a novel cloud-based geospatial modeling approach. Geospatial data of 145,134 cities and villages and 8,067 HCF were gathered with land coverage types, roads and river networks, and digital elevation data to produce high-resolution (30 m) estimates of travel time to HCFs across Peru. This study estimated important variations in travel time to HCFs between urban and rural settings and major land coverage types in Peru. The median travel time to primary, secondary, and tertiary HCFs was 1.9-, 2.3-, and 2.2-fold higher in rural than urban settings, respectively. This study provides a new methodology to estimate the travel time to HCFs as a tool to enhance the understanding and characterization of the profiles of accessibility to HCFs in low- and middle-income countries.

Malaria vector species in Amazonian Peru co-occur in larval habitats but have distinct larval microbial communities.

In Amazonian Peru, the primary malaria vector, Nyssorhynchus darlingi (formerly Anopheles darlingi), is difficult to target using standard vector control methods because it mainly feeds and rests outdoors. Larval source management could be a useful supplementary intervention, but to determine its feasibility, more detailed studies on the larval ecology of Ny. darlingi are essential. We conducted a multi-level study of the larval ecology of Anophelinae mosquitoes in the peri-Iquitos region of Amazonian Peru, examining the environmental characteristics of the larval habitats of four species, comparing the larval microbiota among species and habitats, and placing Ny. darlingi larval habitats in the context of spatial heterogeneity in human malaria transmission. We collected Ny. darlingi, Nyssorhynchus rangeli (formerly Anopheles rangeli), Nyssorhynchus triannulatus s.l. (formerly Anopheles triannulatus s.l.), and Nyssorhynchus sp. nr. konderi (formerly Anopheles sp. nr. konderi) from natural and artificial water bodies throughout the rainy and dry seasons. We found that, consistent with previous studies in this region and in Brazil, the presence of Ny. darlingi was significantly associated with water bodies in landscapes with more recent deforestation and lower light intensity. Nyssorhynchus darlingi presence was also significantly associated with a lower vegetation index, other Anophelinae species, and emergent vegetation. Though they were collected in the same water bodies, the microbial communities of Ny. darlingi larvae were distinct from those of Ny. rangeli and Ny. triannulatus s.l., providing evidence either for a species-specific larval microbiome or for segregation of these species in distinct microhabitats within each water body. We demonstrated that houses with more reported malaria cases were located closer to Ny. darlingi larval habitats; thus, targeted control of these sites could help ameliorate malaria risk. The co-occurrence of Ny. darlingi larvae in water bodies with other putative malaria vectors increases the potential impact of larval source management in this region.

High-accuracy detection of malaria vector larval habitats using drone-based multispectral imagery.

Interest in larval source management (LSM) as an adjunct intervention to control and eliminate malaria transmission has recently increased mainly because long-lasting insecticidal nets (LLINs) and indoor residual spray (IRS) are ineffective against exophagic and exophilic mosquitoes. In Amazonian Peru, the identification of the most productive, positive water bodies would increase the impact of targeted mosquito control on aquatic life stages. The present study explores the use of unmanned aerial vehicles (drones) for identifying Nyssorhynchus darlingi (formerly Anopheles darlingi) breeding sites with high-resolution imagery (~0.02m/pixel) and their multispectral profile in Amazonian Peru. Our results show that high-resolution multispectral imagery can discriminate a profile of water bodies where Ny. darlingi is most likely to breed (overall accuracy 86.73%- 96.98%) with a moderate differentiation of spectral bands. This work provides proof-of-concept of the use of high-resolution images to detect malaria vector breeding sites in Amazonian Peru and such innovative methodology could be crucial for LSM malaria integrated interventions.

Efecto del extracto etanólico de Chuquiraga spinosa (huamanpinta) sobre el síndrome metabólico e hipercolesterolemia inducida en ratas / Effect of ethanol extract of Chuquiraga spinosa (huamanpinta) on the metabolic syndrome and hypercholesterolemia induced in rats

Objetivo: Determinar el efecto del extracto etanólico de Chuquiraga spinosa (huamanpinta) sobre el síndrome metabólico (SM) e hipercolesterolemia inducidas en ratas con fructosa y colesterol. Materiales y Métodos: Se indujo el SM con la administración vía oral de fructosa al 60% P/V durante 90 días y la inducción de hipercolesterolemia fue mediante la administración oral de solución de colesterol a una dosis diaria de 120 mg/kg suspendida en goma de tragacanto al 2%. Se formaron 06 grupos de 15 animales cada grupo, dividido en grupo blanco negativo (solución salina fisiológica) y positivo (fructosa más colesterol), extracto etanólico a dosis de 50, 250 y 500 mg/kg y un grupo atorvastatina más enalapril a 20 mg/kg (se administró fructosa más colesterol a todos los grupos). Los tratamientos respectivos se iniciaron en el día 31 posinducción y se continuó con la inducción coadministrando los tratamientos hasta los 90 días. Se determinó el perfil lipídico, glicemia y niveles de presión arterial. En la determinación de la toxicidad crónica se realizó la evaluación a nivel hematológico y bioquímico de todos los grupos que fueron inducidos y recibieron tratamiento. Resultados: Se obtuvo una disminución de los niveles de colesterol total, triglicéridos, glucosa, presión arterial y del peso corporal, así como una elevación de los niveles de HDL-colesterol, que fueron estadísticamente significativos (p<0,05). En la determinación de la toxicidad crónica se observo que no hubo toxicidad y no se evidenció alteraciones anatomopatológicas. Conclusiones: El extracto etanólico de Chuquiraga spinosa presenta efecto positivo sobre los niveles de perfil lipídico, glucosa y presión arterial inducido en ratas, sin efectos tóxicos.

Objective: To determine the effect of ethanolic extract of Chuquiraga spinosa (huamanpinta) on the metabolic syndrome and hypercholesterolemia in rats induced with fructose and cholesterol. Material and methods: SM was induced in rats with oral administration of 60% fructose for 90 days and the induction of hypercholesterolemia was by oral administration of cholesterol solution at a daily dose of 120 mg/kg suspended in gum tragacanth 2 %. Six groups of 15 animals were formed in each group, divided into negative white group (physiological saline solution) and positive (fructose plus cholesterol), ethanolic extract at doses of 50, 250 and 500 mg/kg and one atorvastatin plus enalapril group at 20 mg/Kg. The respective treatments were initiated on day 31 postinduction and continued induction along with treatments up to 90 days. The lipid profile, glycemia and blood pressure levels were determined. In the determination of chronic toxicity, hematological and biochemical evaluation of all the groups that were induced and treated were performed. Results: There was a decrease in total cholesterol, triglycerides, glucose, blood pressure and body weight, as well as a rise in HDL-cholesterol levels, which were statistically significant (p <0.05). In the determination of chronic toxicity, it was observed that there was no toxicity and no anatomopathological alterations were evidenced. Conclusions: The ethanolic extract of Chuquiraga spinosa has a positive effect on the metabolic syndrome and induced hypercholesterolemia in rats, without toxic effects.

Biodegradación de fenol en aguas tratadas de la industria petrolera para re-uso en cultivos agrícolas / Biodegradation of phenol in treated water from the oil industry to re-use in agricultural crops

ResumenLa explotación del petróleo y el uso de sus derivados han contribuido para el desarrollo tecnológico a nivel mundial. Esta actividad, no obstante, genera muchos subproductos los cuales atentan contra la salud del ambiente. Las aguas de producción, por ejemplo, pueden contener trazas de metales pesados e hidrocarburos, razón por la cual deben ser reincorporadas de forma adecuada al ambiente. En este trabajo, se aislaron, caracterizaron e identificaron molecularmente ocho bacterias en base a su capacidad para degradar fenol. Primero, se evaluó el crecimiento y la degradación de fenol bajo diferentes concentraciones (500, 800 y 1 200 mg / L), y posteriormente se emplearon diseños estadísticos para la selección de condiciones óptimas de degradación. Los resultados mostraron que las ocho cepas evaluadas fueron capaces de usar el fenol como fuente única de carbono; no obstante, las cinéticas de degradación y la máxima tolerancia de las cepas al fenol variaron ampliamente. Debido a su tolerancia y capacidad para metabolizar fenol, la cepa Pseudomonas sp. Sps1 fue seleccionada para posteriores estudios. Mediante el uso de un diseño de Plackett Burman y un diseño factorial fraccionado en el cual diferentes fuentes de carbono, nitrógeno, y fósforo fueron evaluadas y degradación de fenol fue usado como variable de respuesta, fue posible seleccionar las condiciones óptimas para la degradación de fenol por Sps1. Finalmente, se emplearon estas condiciones para evaluar la degradación de fenol en aguas de re-uso provenientes directamente de la industria petrolera. Los resultados, mostraron que la bioestimulación favoreció el proceso de degradación del fenol comparado con el control. En conclusión, en este estudio se demostró que la bioaumentación con bacterias nativas acompañada de bioestimulación generan una tecnología económica y ambientalmente amigable para la remoción de contaminantes en aguas residuales tratadas de la industria petrolera.

AbstractOil exploitation and the usage of its derivatives have undeniably contributed to the technological advance worldwide. This industrial activity, however, generates several by-products that can threaten environmental sustainability. Seawage, for example, can contain organic pollutants and heavy metals; therefore, its deposition must be preceded by adequate water treatment. In this study, we isolated, characterized, and molecularly identified eight bacteria on the basis of their capability to degrade phenol. First, we determined the rates of bacterial growth and phenol degradation using different concentrations of the aromatic hydrocarbon (500, 800 and 1 200 mg / L), and then used sequential statistical designs to select optimal conditions for its degradation. Results showed that all isolated strains were capable of degrading phenol as the sole carbon source; the degradation kinetics and phenol tolerance, however, widely varied among strains. We chose the strain Pseudomonas sp. Sps1 for further studies due to its remarkable tolerance and capability to degrade phenol. By using a Plackett Burman design, followed by a fractionated factorial design in which several carbon, nitrogen, and phosphorus sources were evaluated, and phenol degradation was used as the response variable, we found optimal conditions for phenol degradation by Sps1. Finally, we compared phenol degradation in seawage by the use or not of the optimal conditions established by the statistical methods. Results showed that biostimulation dramatically increased phenol degradation compared with the control. In conclusion, we found that bioaugmentation with the native bacteria Sps1 and a statistically-based biostimulation approach provided an economically and environmentally friendly alternative for the removal of pollutants from oil industry sewage.

Nutrición enteral temprana en trauma abdominal: Hospital Eugenio Espejo 1994-1999

La terapia nutricional, constituye una técnica de soporte en pacientes traumatizados, por cuanto constituye una opción terapéutica de sostén nutricional en pacientes cuya ingesta nutricional por vía oral es limitada. Varios estudios han demostrado su importancia en relación con la recuperación de este tipo de pacientes. El presente estudio, pretende establecer la relación existente entre aporte nutricional adecuado y temprano con la recuperación, mortalidad y complicaciones de pacientes, ingresados con trauma abdominal penetrante y contuso a la Unidad de Terapia Intensiva del Hospital Eugenio Espejo, aplicando un diseño descriptivo de series de casos clínicos. El total de pacientes estudiados fue de 52, con una promedio de 34 años...