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Malaria incidence is generally lower in cities than rural areas. However, reported urban malaria incidence may not accurately reflect the level of ongoing transmission, which has potentially large implications for prevention efforts. To guide mosquito net distribution, we assessed the extent of malaria transmission in Conakry, Guinea, in 2018. We found evidence of active malaria transmission.

Resumen Introducción. El desarrollo de las imágenes diagnósticas hizo posible el diagnóstico topográfico de los tumores de mediastino; sin embargo, aún con los avances actuales de la cirugía, la anestesiología y la reanimación, el acceso quirúrgico a ese espacio medio de la caja torácica continúa siendo el gran reto que enfrentan los cirujanos torácicos. Objetivo. Profundizar en los diferentes aspectos cognoscitivos actualizados sobre los tumores mediastinales. Métodos. Búsqueda documental digital en bases de datos: Scielo, Lilacs, Web of Science, PubMed, realizada en enero de 2019, de publicaciones sobre el tema en la presente centuria. Resultados. Las neoplasias mediastinales son poco frecuentes, pueden aparecer a cualquier edad, aunque son más frecuentes entre la tercera y quinta décadas, y la mayoría se descubren incidentalmente en una radiografía de tórax de rutina en pacientes asintomáticos. Los tumores malignos del mediastino son poco frecuentes, pero los benignos constituyen un desafío diagnóstico para radiólogos y patólogos. En las neoplasias malignas se identifica una amplia gama de variedades histológicas, atribuibles a las características del órgano afectado. Conclusiones. El diagnóstico definitivo generalmente se establece mediante el estudio histopatológico posquirúrgico, si bien la tomografía computarizada, asociada o no a la biopsia percutánea, es el estándar de oro para el diagnóstico preoperatorio. La selección de la vía de entrada al tórax, así como el procedimiento quirúrgico, están condicionados por la localización y el tamaño del tumor en el mediastino. Abstract Introduction. The development of diagnostic images made the topographic diagnosis of mediastinal tumors possible; however, even with current advances in surgery, anesthesiology, and resuscitation, surgical access to this mid-rib cage space continues to be the great challenge faced by chest surgeons. Objective. To deepen in the different updated cognitive aspects about mediastinal tumors. Methods. Digital documentary search in databases: Scielo, Lilacs, Web of Science, and PubMed, performed in January 2019, of publications on the subject in the present century. Results. Mediastinal neoplasms are rare, they can appear at any age, although they are most common between the third and fifth decades, and most are discovered incidentally on a routine chest radiograph in asymptomatic patients. Malignant tumors of the mediastinum are rare, but benign tumors pose a diagnostic challenge for radiologists and pathologists. In malignant neoplasms, a wide range of histological varieties is identified, attributable to the characteristics of the affected organ. Conclusions. The definitive diagnosis is generally established by postoperative histopathological study, although computed tomography, associated or not with percutaneous biopsy, is the gold standard for preoperative diagnosis. The selection of the entry route to the thorax, as well as the surgical procedure, are conditioned by the location and size of the tumor in the mediastinum.

Introducción: Las neoplasias mediastinales son tumores poco frecuentes, pueden aparecer a cualquier edad y por lo general se descubren incidentalmente en una radiografía de tórax de rutina en pacientes asintomáticos. Objetivo: Caracterizar a los pacientes operados por tumores de mediastino según variables clínico- epidemiológicas y diagnósticas seleccionadas. Métodos: Se realizó un estudio observacional, descriptivo, de tipo serie de casos con 37 enfermos ingresados y operados con diagnóstico de tumor mediastinal, en el Servicio de Cirugía General del Hospital Provincial Docente "Saturnino Lora" de Santiago de Cuba, durante los años 2010 a 2017. Resultados: Predominó el sexo femenino con 23 pacientes y el intervalo de edad entre 31 y 40 años (11 casos). Los síntomas más comunes fueron dolor torácico, tos y disnea. El compartimiento posterior fue el mayormente afectado (11 pacientes), así como los tumores con tamaños entre 7 y 9 cm (17 enfermos). Los medios diagnósticos más utilizados fueron la tomografía computarizada, la broncoscopia y la mediastinoscopia. Primaron los tumores malignos (54,1 %) en los que se identificó una amplia gama de variedades histológicas. Conclusiones: El diagnóstico definitivo generalmente se establece mediante el estudio histopatológico posquirúrgico, aunque la tomografía computarizada asociada o no a la biopsia percutánea es la regla de oro para el diagnóstico preoperatorio. Las variedades histológicas de los tumores malignos son atribuibles a las características del órgano afectado.

Vector-borne pathogens cause many human infectious diseases and are responsible for high mortality and morbidity throughout the world. They can also cause livestock epidemics with dramatic social and economic consequences. Due to its high costs, vector-borne disease surveillance is often limited to current threats, and the investigation of emerging pathogens typically occurs after the reports of clinical cases. Here, we use high-throughput sequencing to detect and identify a wide range of parasites and viruses carried by mosquitoes from Cambodia, Guinea, Mali and the USA. We apply this approach to individual Anopheles mosquitoes as well as pools of mosquitoes captured in traps; and compare the outcomes of this assay when applied to DNA or RNA. We identified known human and animal pathogens and mosquito parasites belonging to a wide range of taxa, as well as DNA sequences from previously uncharacterized organisms. Our results also revealed that analysis of the content of an entire trap could be an efficient approach to monitor and identify rare vector-borne pathogens in large surveillance studies. Overall, we describe a high-throughput and easy-to-customize assay to screen for a wide range of pathogens and efficiently complement current vector-borne disease surveillance approaches., Summary: We describe a surveillance technique enabling the detection of known and previously uncharacterized pathogens present in mosquitoes. This approach could reduce the costs of vector-borne disease monitoring and provide early warning of emerging diseases.

Vector-borne pathogens cause many human infectious diseases and are responsible for high mortality and morbidity throughout the world. They can also cause livestock epidemics with dramatic social and economic consequences. Due to the high costs, vector-borne disease surveillance is often limited to current threats, and the investigation of emerging pathogens typically occur after the reports of clinical cases. Here, we use high-throughput sequencing to detect and identify a wide range of parasites and viruses carried by mosquitoes from Cambodia, Guinea, Mali and Maryland. We apply this approach to individual Anopheles mosquitoes as well as pools of mosquitoes captured in traps; and compare the outcomes of this assay when applied to DNA or RNA. We identified known human and animal pathogens and mosquito parasites belonging to a wide range of taxa, insect Flaviviruses, and novel DNA sequences from previously uncharacterized organisms. Our results also revealed that analysis of the content of an entire trap is an efficient approach to monitor and identify potential vector-borne pathogens in large surveillance studies, and that analyses of RNA extracted from mosquitoes is preferable, when possible, over DNA-based analyses. Overall, we describe a flexible and easy-to-customize assay that can provide important information for vector-borne disease surveillance and research studies to efficiently complement current approaches.

Background The commensal microbiota of mosquitoes impacts their development, immunity, and competency, and could provide a target for alternative entomological control approaches. However, despite the importance of the mosquito/microbiota interactions, little is known about the relative contribution of endogenous and exogenous factors in shaping the bacterial communities of mosquitoes. Methods We used a high-throughput sequencing-based assay to characterize the bacterial composition and diversity of 665 individual field-caught mosquitoes, as well as their species, genotype at an insecticide resistance locus, blood-meal composition, and the eukaryotic parasites and viruses they carry. We then used these data to rigorously estimate the individual effect of each parameter on the bacterial diversity as well as the relative contribution of each parameter to the microbial composition. Results Overall, multivariate analyses did not reveal any significant contribution of the mosquito species, insecticide resistance, or blood meal to the bacterial composition of the mosquitoes surveyed, and infection with parasites and viruses only contributed very marginally. The main driver of the bacterial diversity was the location at which each mosquito was collected, which explained roughly 20% of the variance observed. Conclusions This analysis shows that when confounding factors are taken into account, the site at which the mosquitoes are collected is the main driver of the bacterial diversity of wild-caught mosquitoes, although further studies will be needed to determine which specific components of the local environment affect bacterial composition. Graphical Abstract

Background The commensal microbiota of mosquitoes impacts their development, immunity, and competency, and could provide a target for alternative entomological control approaches. However, despite the importance of the mosquito/microbiota interactions, little is known about the relative contribution of genetic and non-genetic factors in shaping the bacterial communities of mosquitoes. Methods We used a high-throughput sequencing based assay to characterize the bacterial composition and diversity of 665 individual field-caught mosquitoes, as well as their species, genotype at an insecticide resistance locus, blood meal composition, and the eukaryotic parasites and viruses they carry. We then used these data to rigorously estimate the individual effect of each parameter on the bacterial diversity as well as their relative contribution to the microbial composition. Results Overall, multivariate analyses did not reveal any significant contribution of the mosquito species, insecticide resistance or blood meal to the bacterial composition of the mosquitoes surveyed. Infection with parasites and viruses only contributed very marginally and the main driver of the bacterial diversity was the location where each mosquito was collected which explained roughly 20% of the variance observed. Conclusions This analysis shows that, when confounding factors are taken into account, the sites where the mosquitoes are collected is the main driver of the bacterial diversity of wild-caught mosquitoes, although further studies will be needed to determine how the specific components of the local environment affecting the bacterial composition.

Background: Wolbachia, a common insect endosymbiotic bacterium that can influence pathogen transmission and manipulate host reproduction, has historically been considered absent from the Anopheles (An.) genera, but has recently been found in An. gambiae s.l. populations in West Africa. As there are numerous Anopheles species that have the capacity to transmit malaria, we analysed a range of species across five malaria endemic countries to determine Wolbachia prevalence rates, characterise novel Wolbachia strains and determine any correlation between the presence of Plasmodium, Wolbachia and the competing bacterium Asaia. Methods: Anopheles adult mosquitoes were collected from five malaria-endemic countries: Guinea, Democratic Republic of the Congo (DRC), Ghana, Uganda and Madagascar, between 2013 and 2017. Molecular analysis was undertaken using quantitative PCR, Sanger sequencing, Wolbachia multilocus sequence typing (MLST) and high-throughput amplicon sequencing of the bacterial 16S rRNA gene. Results: Novel Wolbachia strains were discovered in five species: An. coluzzii, An. gambiae s.s., An. arabiensis, An. moucheti and An. species A, increasing the number of Anopheles species known to be naturally infected. Variable prevalence rates in different locations were observed and novel strains were phylogenetically diverse, clustering with Wolbachia supergroup B strains. We also provide evidence for resident strain variants within An. species A. Wolbachia is the dominant member of the microbiome in An. moucheti and An. species A but present at lower densities in An. coluzzii. Interestingly, no evidence of Wolbachia/Asaia co-infections was seen and Asaia infection densities were shown to be variable and location dependent. Conclusions: The important discovery of novel Wolbachia strains in Anopheles provides greater insight into the prevalence of resident Wolbachia strains in diverse malaria vectors. Novel Wolbachia strains (particularly high-density strains) are ideal candidate strains for transinfection to create stable infections in other Anopheles mosquito species, which could be used for population replacement or suppression control strategies.

To confirm and investigate possible explanations for unusual trends in malaria indicators, a protocol for rapid, focal assessment of malaria transmission and control interventions was piloted in N'Zerekore and Macenta Prefectures, which each reported surprisingly low incidence of malaria during the peak transmission months during 2017 in holoendemic Forested Guinea. In each prefecture, epidemiological and entomological cross-sectional surveys were conducted in two sub-prefectures reporting high incidence and one sub-prefecture reporting low incidence. Investigators visited six health facilities and 356 households, tested 476 children, performed 14 larval breeding site transects, and conducted 12 nights of human landing catches during the 2-week investigation. Rapid diagnostic test positivity in the community sample of children under five ranged from 23% to 68% by subprefecture. Only 38% of persons with fever reported seeking care in the public health sector; underutilization was confirmed by verification of health facility and community healthcare worker (CHW) registries. High numbers of Anopheles mosquitoes were collected in human landing collections in N'Zerekore (38 per night in combined indoor and outdoor collections) and Macenta (87). Most of the detected breeding sites positive for Anopheles larvae (83%) were shallow roadside puddles. In the investigated prefectures, malaria rates remain high and the low reported incidence likely reflects low utilization of the public health-care sector. Strengthening the CHW program to rapidly identify and treat malaria cases and elimination of roadside puddles as part of routine cleanup campaigns should be considered. Systematic joint epidemiological/entomological investigations in areas reporting anomalous signals in routine data can allow control programs to respond with tailored local interventions.