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The Orthoflavivirus ilheusense (ILHV) is an arbovirus that was first isolated in Brazil in 1944 during an epidemiologic investigation of yellow fever. Is a member of the Flaviviridae family and it belongs to the antigenic complex of the Ntaya virus group. Psorophora ferox is the primary vector of ILHV and this study presents the isolation and phylogenetic analysis of ILHV in a pool of Ps. ferox collected in the state of Goiás in 2021. Viral isolation tests were performed on Vero cells and C6/36 clones. The indirect immunofluorescence test (IFI) was used to confirm the positivity of the sample. The positive sample underwent RT-qPCR, sequencing, and phylogenetic analysis. This is the first report of ILHV circulation in this municipality and presented close relationship between this isolate and another ILHV isolate collected in the city of Belém (PA).

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Objetivo: estimar a oviposição e distribuição espacial de vetores Aedes durante a estação de inverno e correlacionar essas estimativas com dados climáticos do mesmo período. Métodos: estudo de campo conduzido no município de Barbacena-MG, em 2018. O monitoramento, a coleta de ovos e a estimativa de índices estegômicos de vetores Aedes foram obtidos por meio de ovitrampas. Os Índices de Densidade de Ovos (IDO) e de Positividade de Ovitrampas (IPO%) foram estimados conforme estações climáticas e semanas epidemiológicas. A correlação entre parâmetros meteorológicos (temperatura/pluviometria) e índices estegômicos (IDO/IPO) foi determinada pelo coeficiente de Spearman. Resultados: um total de 1.080 ovitrampas, instaladas em 39 bairros, foi analisado durante 10 semanas epidemiológicas, fornecendo um total de 970 ovos. Nas estações de outono, inverno e primavera, foram obtidos, respectivamente, 421, 470 e 70 ovos. Durante o outono, houve variação do IDO entre 14,2 e 34,2. O IPO manteve-se constante em 4,5%. Durante o inverno, houve variação do IDO entre 0,00 e 47,50 e do IPO entre 0,00% e 8,25%. Houve correlação negativa significativa tanto entre aumento da precipitação mensal e diminuição do número de ovos coletados (rho=-0.673) quanto entre aumento da precipitação mensal e diminuição do IPO (rho=-0.612). O valor geral do IDO e do IPO nas 10 semanas foi, respectivamente, 22,04 e 4,17% e, na estação de inverno, foi, respectivamente, 23,50 e 3,73%. Conclusão: os achados corroboram a presença de ovos e vetores do gênero Aedes mesmo em condições climáticas adversas para essas espécies e sustentam ações de manejo sanitário durante todo o ano.

Objective: to estimate oviposition and spatial distribution of Aedes vectors during the winter season and correlate these estimates with climate data from the same period. Methods: field study conducted in the municipality of Barbacena-MG in 2018. Monitoring, egg collection, and estimation of stegomic indices of Aedes were obtained using ovitraps. The Indices of Egg Density (EDI) and Positive Ovitrap (POI%) were estimated according to climatic seasons and epidemiological weeks. The correlation between meteorological parameters (temperature/rainfall) and stegomic indices (EDI/POI) was determined by the Spearman coefficient. Results: a total of 1,080 ovitraps installed in 39 neighborhoods were analyzed during ten (10) epidemiological weeks, providing a total of 970 eggs. In the autumn, winter, and spring seasons, 421, 470, and 70 eggs were obtained, respectively. During the autumn, there was a variation in EDI between 14.2­34.2. The POI remained constant at 4.5%. During the winter, the EDI varied between 0.00­47.50, and the POI varied between 0.00%­8.25%. There was a significant negative correlation, respectively, between an increase in monthly precipitation and a decrease in the number of eggs collected (rho=-0.673) and between an increase in monthly precipitation and a decrease in POI (rho=-0.612). The overall value of EDI and POI in the ten (10) weeks was 22.04 and 4.17%, and in the winter season, they were 23.50 and 3.73%, respectively. Conclusion: the findings corroborate the presence of eggs and vectors of the genus Aedes even in adverse climatic conditions for these species and support health management actions throughout the year.

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BACKGROUND: Low-income urban communities in the tropics often lack sanitary infrastructure and are overcrowded, favoring Aedes aegypti proliferation and arboviral transmission. However, as Ae. aegypti density is not spatially homogeneous, understanding the role of specific environmental characteristics in determining vector distribution is critical for planning control interventions. The objectives of this study were to identify the main habitat types for Ae. Aegypti, assess their spatial densities to identify major hotspots of arbovirus transmission over time and investigate underlying factors in a low-income urban community in Salvador, Brazil. We also tested the field-collected mosquitoes for arboviruses. METHODS: A series of four entomological and socio-environmental surveys was conducted in a random sample of 149 households and their surroundings between September 2019 and April 2021. The surveys included searching for potential breeding sites (water-containing habitats) and for Ae. aegypti immatures in them, capturing adult mosquitoes and installing ovitraps. The spatial distribution of Ae. aegypti density indices were plotted using kernel density-ratio maps, and the spatial autocorrelation was assessed for each index. Visual differences on the spatial distribution of the Ae. aegypti hotspots were compared over time. The association of entomological findings with socio-ecological characteristics was examined. Pools of female Ae. aegypti were tested for dengue, Zika and chikungunya virus infection. RESULTS: Overall, 316 potential breeding sites were found within the study households and 186 in the surrounding public spaces. Of these, 18 (5.7%) and 7 (3.7%) harbored a total of 595 and 283 Ae. aegypti immatures, respectively. The most productive breeding sites were water storage containers within the households and puddles and waste materials in public areas. Potential breeding sites without cover, surrounded by vegetation and containing organic matter were significantly associated with the presence of immatures, as were households that had water storage containers. None of the entomological indices, whether based on immatures, eggs or adults, detected a consistent pattern of vector clustering in the same areas over time. All the mosquito pools were negative for the tested arboviruses. CONCLUSIONS: This low-income community displayed high diversity of Ae. aegypti habitats and a high degree of heterogeneity of vector abundance in both space and time, a scenario that likely reflects other low-income communities. Improving basic sanitation in low-income urban communities through the regular water supply, proper management of solid wastes and drainage may reduce water storage and the formation of puddles, minimizing opportunities for Ae. aegypti proliferation in such settings.

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Fundamento el conocimiento acerca de la focalidad por mosquitos motiva a pobladores y decisores a trabajar sobre las cuestiones que inciden en la proliferación de estos vectores; así como a una participación comunitaria eficaz, y el éxito en la prevención y control de las arbovirosis. Objetivo caracterizar los focos de mosquitos Aedes aegypti. Métodos se realizó un estudio observacional, retrospectivo, y de corte transversal, acerca de los focos de Aedes aegypti detectados en el municipio de Abreus, provincia de Cienfuegos, en el período 2016-2022. El universo fue de 390 focos, para los cuales se describieron las variables: semana estadística, mes y año de diagnóstico, consejo popular, tipo de depósito, lugar de la vivienda donde se encontró y fase del mosquito al diagnóstico. Se utilizaron datos de las encuestas entomológicas y los registros del laboratorio de Entomología Médica de la Unidad Municipal de Higiene y Epidemiología. Resultados la mediana del número de focos de Aedes aegypti correspondió a la semana estadística 32 de cada año. La mayor cantidad de focos se detectó en los consejos populares de Abreus (165) y Juraguá (102); hallados sobre todo en patios (85,5 %) y tanques bajos (55,5 %). Predominó la fase larvaria en IV estadio (82,3 %). Conclusiones en el municipio de Abreus la focalidad por mosquitos Aedes aegypti se caracterizó por su mayor incidencia en los meses de junio a septiembre, con predominio en el consejo popular de Abreus, sobre todo en tanques bajos y patios. El mayor número fue diagnosticado en la IV fase.

Background knowledge about the mosquito's breeding grounds motivates residents and decision makers to work on the issues that affect the mosquito proliferation; as well as effective community participation, and success in the prevention and control of arboviral diseases. Objective to characterize the Aedes aegypti mosquito's breeding grounds. Methods an observational, retrospective, and cross-sectional study was carried out on Aedes aegypti's breeding grounds detected in the Abreus municipality, Cienfuegos province, from 2016 to 2022. 390 breeding grounds were the universe, for which the described variables were: statistical week, month and year of diagnosis, neighborhood, type of deposit, place of residence where it was found, and phase of the mosquito at diagnosis. Data from entomological surveys and records from the Municipal Hygiene and Epidemiology Unit's Medical Entomology laboratory were used. Results the median number of Aedes aegypti breeding grounds corresponded to statistical week 32 of each year. The largest number of outbreaks was detected in the Abreus' neighborhood (165) and Juraguá (102); found mainly in yards (85.5 %) and low tanks (55.5 %). The larval phase in IV stage predominated (82.3 %). Conclusions in the municipality of Abreus, the focality of Aedes aegypti mosquitoes was characterized by its highest incidence in the months of June to September, with predominance in the popular council of Abreus, especially in low tanks and yards. The largest number was diagnosed in the IV phase.

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Aedes aegypti and Aedes albopictus are the vectors of important arboviruses: dengue fever, chikungunya, Zika, and yellow fever. Female mosquitoes acquire arboviruses by feeding on the infected host blood, thus being able to transmit it to their offspring. The intrinsic ability of a vector to infect itself and transmit a pathogen is known as vector competence. Several factors influence the susceptibility of these females to be infected by these arboviruses, such as the activation of the innate immune system through the Toll, immunodeficiency (Imd), JAK-STAT pathways, and the interference of specific antiviral response pathways of RNAi. It is also believed that the presence of non-pathogenic microorganisms in the microbiota of these arthropods could influence this immune response, as it provides a baseline activation of the innate immune system, which may generate resistance against arboviruses. In addition, this microbiome has direct action against arboviruses, mainly due to the ability of Wolbachia spp. to block viral genome replication, added to the competition for resources within the mosquito organism. Despite major advances in the area, studies are still needed to evaluate the microbiota profiles of Aedes spp. and their vector competence, as well as further exploration of the individual roles of microbiome components in activating the innate immune system.

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Introduction: In Colombia, malaria affects people in vulnerable conditions. In urban areas, disease control measures have decreased the incidence of malaria in the past 5 years. However, there is some government abandonment in areas with armed conflict. Objective: To determine the knowledges, attitudes and practice regarding malaria in Piñalito, a town located in the municipality of Vista Hermosa in the Meta department (Colombia), in the period 2016-2017. Methods: We conducted a mixed-methods study using a survey consisting of 45 questions on knowledge, attitudes, and practices and semistructured interviews with medical personnel and government workers. Results: Of the respondents, 89.13% said that malaria is a health problem, 63.04% said the disease is transmitted by a mosquito bite, main symptoms were reported to be high fever (78.26%) and headache (60.87%). A total of 73.91% of respondents affirmed using mosquito nets to avoid the disease. The community affirmed that they do not receive good medical attention (65.22%) and did not identify the active participation of the local health secretary to prevent malaria. Conclusions: The inhabitants of Piñalito demonstrated adequate knowledge about the disease and positive attitudes toward preventing malaria. However, they had negative perceptions about the actions of the secretary of health and the government for control and prevention of the disease.

Introducción: En Colombia, la malaria afecta a personas en condiciones de vulnerabilidad. En áreas urbanas, las medidas de control de enfermedades han disminuido la incidencia de malaria en los últimos 5 años. Sin embargo, existe cierto abandono del gobierno en áreas con conflicto armado. Objetivo: Determinar los conocimientos, actitudes y prácticas sobre la malaria en la población del municipio de Piñalito (Meta, Colombia), en el periodo 2016-2017. Métodos: Realizamos un estudio de métodos mixtos utilizando una encuesta de 45 preguntas sobre conocimientos, actitudes y prácticas de la población y entrevistas semiestructuradas con personal médico y trabajadores del gobierno. Resultados: De los encuestados, el 89,13 % dijo que la malaria es un problema de salud, el 63,04 % considera que la enfermedad se transmite por la picadura de un mosquito. Los síntomas principales fueron fiebre alta (78,26 %) y dolor de cabeza (60,87 %). El 73,91 % de los encuestados afirmó utilizar mosquiteros para evitar la enfermedad. La comunidad manifestó que no recibe buena atención médica (65,22 %) y no identificó la participación activa de la secretaría de salud local para prevenir la malaria. Conclusiones: Los habitantes de Piñalito demostraron un adecuado conocimiento sobre la enfermedad y actitudes positivas hacia la prevención de la malaria. Sin embargo, tenían percepciones negativas sobre las acciones de la secretaría de salud y del gobierno para el control y prevención de la enfermedad.

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The Atlantic Forests outside of the Amazon region in Brazil are low-frequency malaria hotspots. The disease behaves as a zoonosis maintained by nonhuman primates (NHPs), especially howler monkeys. Between 2016 and 2018, Brazil witnessed the largest yellow fever outbreak since 1980, resulting in massive declines in these NHP populations. However, reports of malaria cases continued in transmission areas. This scenario motivated this survey to determine the frequency of infection of the anophelines by Plasmodium species. Mosquitoes were captured using Shannon traps and CDC light traps and identified as to species based on morphological characters. The screening for malaria parasites targeted only Anopheles species belonging to the subgenus Kerteszia, the proven primary malaria vector. A TaqMan qPCR assay using ribosomal primers (18S rRNA gene) was performed in a Step One Plus Real-time PCR to detect Plasmodium species. Seven hundred sixty field-caught anophelines divided into 76 pools were examined. Out of 76 tested pools, seven (9.21%) were positive. Three pools were Plasmodium malariae-positive, and four were Plasmodium vivax-positive. The anopheline infection was expressed as the maximum infection rate (MIR), disclosing a value of 0.92%, indicative of a steady state. Such stability after the yellow fever outbreak suggests that other species of NHPs could support transmission.

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Abstract Introduction: Tropical Andean and Amazonian ecosystems shape the great biodiversity found in Peru. However, studies on mosquitoes (Diptera: Culicidae) in the country are scarce, resulting in an information gap regarding their diversity, ecology, distribution, and abundance. Objective: To search for documented evidence on the diversity and distribution of mosquitoes (Diptera: Culicidae) in Peru, and to establish -in relation to species of medical relevance- their potential link with the epidemiological cycle of some metaxenic diseases. Materials and methods: A literature review was conducted in Google Scholar, ScienceDirect, PubMed, and SciELO, as well as in 7 databases specialized in insect taxonomy, using specific terms and their combinations by means of Boolean operators ("AND" and "OR"). Search strategy: study types: original research articles, review articles, books, and book chapters; publication period: no initial date - June 2020; languages: English, Spanish, and Portuguese. Results: A total of 99 studies were retrieved after the initial search, 84 in the 4 electronic databases and 15 in the specialized databases, of which 41 met the inclusion criteria. One additional record was included due to its relevance to the objective of the review. The studies included were original articles (n=28), review articles (n=6), books (n=5), book chapters (n=2), and undergraduate theses (n=1). Regarding the language of publication, 25 (59.52%) were published in English and 17 (40.48%) in Spanish. Conclusions: In Peru, the greatest diversity of mosquito genera is found in the departments of Loreto, Huánuco, and Madre de Dios. Knowledge of the diversity of mosquitoes in Peru that have the potential to cause health issues is relatively scarce and is focused on Aedes aegypti and some species of the Anopheles and Culex genera, thus overlooking a rich diversity distributed in the Amazonian forests, high jungle, and inter-Andean valleys.

Resumen Introducción. Los ecosistemas tropicales andinos y amazónicos determinan la gran biodiversidad presente en Perú. Sin embargo, los estudios sobre mosquitos (Diptera: Culicidae) en el país son escasos, lo que resulta en un vacío de información en cuanto a su diversidad, ecología, distribución y abundancia. Objetivos. Buscar evidencia documentada sobre la diversidad y la distribución de mosquitos en el Perú, y establecer -con relación a las especies de importancia médica- su potencial vínculo con el ciclo epidemiológico de algunas enfermedades metaxénicas. Materiales y métodos. Se realizó una revisión de la literatura en Google Académico, ScienceDirect, PubMed y Scielo, así como en siete bases de datos especializadas en taxonomía de insectos, usando términos específicos y diferentes combinaciones con operadores booleanos ("AND" y "OR"). Estrategia de búsqueda: tipos de estudios: artículos originales de investigación, artículos de revisión, libros y capítulos de libros; periodo de publicación: sin límite inicial a junio del 2020; idiomas: inglés, español y portugués. Resultados. La búsqueda inicial arrojó 99 estudios, 84 en las 4 bases de datos electrónicas y 15 en las bases de datos especializadas, de los cuales 41 cumplieron los criterios de inclusión. También se incluyó un registro adicional debido a su relevancia con el objetivo de la revisión. Los estudios incluidos fueron artículos originales (n=28), artículos de revisión (n=6), libros (n=5), capítulos de libro (n=2) y tesis de pregrado (n=1). Respecto al idioma de publicación, 25 (59.52%) estaban en inglés y 17 (40.48%), en español. Conclusiones. En Perú, la mayor diversidad de géneros de mosquitos se encuentra presente en los departamentos de Loreto, Huánuco y Madre de Dios. El conocimiento sobre la diversidad de mosquitos en Perú que tienen el potencial de generar problemas de salud es relativamente escaso y se centra en el Aedes aegypti y algunas especies de los géneros Anopheles y Culex, dejando de lado una rica diversidad distribuida en los bosques amazónicos, la selva alta y los valles interandinos.

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Using collection methods for Aedes adults as surveillance tools provides reliable indices and arbovirus detection possibilities. This study compared the effectiveness of different methods for collecting Ae. aegypti and Ae. albopictus and detecting arboviruses circulating in field-caught female specimens. Collection sites were defined in urban, peri-urban, and rural landscapes in two Brazilian cities. Collections were performed using Adultraps (ADT), BG-Sentinel (BGS), CDC-like traps (CDC), and indoor (ASP-I) and outdoor (ASP-O) aspiration during the rainy and dry seasons of 2015 and 2016. Generalized linear mixed models were used to model the effectiveness of each collection method. A total of 434 Ae. aegypti and 393 Ae. albopictus were collected. In total, 64 Ae. aegypti and sixteen Ae. albopictus female pools were tested for DENV, CHIKV, ZIKV, or YFV; none were positive. Positivity and density were linear at low densities (<1 specimen); thereafter, the relationship became non-linear. For Ae. aegypti, ADT and CDC were less effective, and ASP-I and ASP-O were as effective as BGS. For Ae. albopictus, all collection methods were less effective than BGS. This study highlights the need for an integrated surveillance method as an effective tool for monitoring Aedes vectors.

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The yellow fever (YF) virus has been detected throughout Brazil, with the occurrence of human cases, cyclic epizootics, and its isolation from Haemagogus janthinomys and Hg. leucocelaenus. We assessed the seasonal occurrence, egg abundancy, and oviposition interaction of mosquito vector species captured at a Private Natural Heritage Reserve in the Atlantic Forest biome. A total of 2943 eggs and 1538 mosquito larvae were collected from which 1231 belonged to entomologically important species. Ovitraps were used to collect immature mosquitoes from September 2019 to January 2021. The Mann-Whitney test was used to assess the differences in the abundance of eggs between rainy and dry seasons. Kruskal-Wallis and Dunn's post hoc tests were used to evaluate the significance of the differences in the number of individuals from vector species. The highest percentage of mosquito vector eggs were collected during the rainy season, from December to February. Most eggs recovered from ovitraps belonged to the species Hg. leucocelaenus, representing 85% of all mosquito eggs identified. The other species had lower abundances and percentages: Aedes terrens (7%), Haemagogus janthinomys (5%) and Aedes albopictus (3%). The species that shared breeding sites with a higher frequency were Hg. leucocelaenus and Hg. janthinomys, with a statistically positive correlation (ρ = 0.74). This finding suggests that maybe the presence of Hg. leucocelaenus eggs acted as an attractant for Hg. janthinomys or vice versa. An understanding of mosquito oviposition behavior is necessary for the development of surveillance and control approaches directed against specific pathogen vectors of medical and veterinary importance.

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RESUMEN Objetivos: Conocer la diversidad genética de Aedes aegypti en el corredor vial transfronterizo Central-Alto Paraná de Paraguay, con registros de casos de dengue. Materiales y métodos: Se seleccionaron veinte hembras adultas de la eclosión de huevos de Ae. aegypti procedentes de casas geolocalizadas en los departamentos de Alto Paraná, Caaguazú, Cordillera y Central, entre el 2018 y 2019. Se extrajo ADN del tejido de las hembras para amplificación aleatoria de sus patrones polimórficos mediante amplificación aleatoria del ADN polimórfico por PCR (RAPD-PCR), usando cebadores H3 y B03 a fin de conocer parámetros genéticos de diversidad poblacional. Las relaciones entre las poblaciones de mosquitos según la localidad fueron visualizadas mediante análisis no apareado de la media aritmética. Las áreas idóneas de distribución geográfica real y potencial de estas poblaciones de Ae. aegypti fueron analizadas mediante DIVA-GIS 7.3.0 y MAXENT. Resultados: Se identificaron 40 loci mediante perfiles RAPD-PCR, con diferenciación génica moderada (Gst = 0,12). El corredor transfronterizo presentó condiciones bioclimáticas para la presencia de poblaciones variantes de Ae. aegypti, siendo determinantes en la distribución la precipitación del trimestre más cálido y la temperatura media del trimestre más seco. Conclusiones: Se evidencia que existe diversidad genética moderada en las poblaciones de Ae. aegypti procedentes de zonas con registros de casos de dengue ubicadas en el corredor vial transfronterizo que une los departamentos Central y Alto Paraná de Paraguay. El estudio de variabilidad genética de Ae. aegypti es de gran utilidad para la vigilancia entomoepidemiológica y evaluación de posibles eventos de resistencia al control químico.

ABSTRACT Objective: To determine the genetic diversity of Aedes aegypti in the Central-Alto Paraná cross-border road corridor of Paraguay, an area that has reports of dengue cases. Materials and methods: Twenty adult females were selected from hatching Ae. aegypti eggs from households geolocated in the departments of Alto Paraná, Caaguazú, Cordillera and Central, between 2018 and 2019. DNA was extracted from the tissue of females for amplifying their polymorphic patterns by random amplification of polymorphic DNA by PCR (RAPD-PCR), using primers H3 and B03 in order to identify genetic parameters of population diversity. The relationships between mosquito populations according to locality were observed by unpaired arithmetic mean analysis. We used DIVA-GIS 7.3.0 and MAXENT to analyze the suitable areas of actual and potential geographic distribution of these Ae. aegypti populations. Results: Forty loci were identified by RAPD-PCR profiling, with moderate gene differentiation (Gst = 0.12). The cross-border corridor presented bioclimatic conditions for the presence of variant populations of Ae. aegypti, with precipitation in the warmest quarter and mean temperature in the driest quarter being determinant in the distribution. Conclusions: There is evidence of moderate genetic diversity in Ae. aegypti populations from areas that have reported dengue cases in the cross-border road corridor linking the Central and Alto Paraná departments of Paraguay. The study of genetic variability of Ae. aegypti is very useful for entomo-epidemiological surveillance and evaluation of possible resistance to chemical control.

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RESUMEN Las actinobacterias incluyen miembros productores de compuestos multipropósitos restringidamente sobreexplotados al género Streptomyces. No obstante, es necesario reorientar la exploración de bacterias no estreptomiceas para el uso de nuevos bioagentes ecológicos con miras a evitar redescubrimientos y contrarrestar la resistencia a insecticidas químicos en Aedes aegypti. En esta investigación, se caracterizó actinobacterias formadoras de biopelículas para evaluar su dinámica de crecimiento, actividad larvicida y efectos subletales. La identificación, crecimiento y bioactividades de los patógenos se realizaron por cultivos, análisis de imágenes por fotomicrografía y bioensayos. Las biopelículas pertenecen a Pseudonocardiaceae (PsA1TA) y Corynebacteriaceae (CoA2CA) característicamente dependientes a crecer sobre sustratos con revestimiento cuticular específico. PsA1TA coloniza estructuras membranosas de tórax y abdomen de larvas. Las microcolonias desarrollan infectivamente a biopelículas mono y biestratificadas hasta cubrir cuatro veces la amplitud toracoabdominal (envergadura infectiva entre 1010 μm a 1036 μm). En contraste, CoA2CA envuelve radialmente estructuras esclerotizadas cefálica y anal al triplicar la amplitud de los órganos infectados (envergadura infectiva: 1820 a 2030 μm y 1650 a 1860 μm, respectivamente). Las biopelículas ejercen mortalidad diferenciada a todas las etapas larvarias, no obstante, PsA1TA resultó más mortal y virulento frente al segundo estadio (58 %-96 horas, TL50: 3,4 días), mientras que CoA2CA lo fue sobre el cuarto estadio larval (85 %-96 horas, TL50: 2,5 días). CoA2CA indujo emergencia incompleta de farados y despliegue de tarsos curvos en adultos emergentes, además de revestir cadáveres larvarios con robustas biopelículas. Los morfotipos actinobacterianos revelan efecto larvicida y subletal en A. aegypti por formación de biopelículas.

ABSTRACT Actinobacteria include several ubiquitous members involved in the synthesis of multipurpose bioactive compounds strictly derived from the genus Streptomyces. Nevertheless, new bacterial consortia based on non-streptomycetes actinobacteria are needed to be explored in order to avoid rediscoveries and minimize the development of insecticide resistance in Aedes aegypti. In accordance with the use of eco-friendly bioagents, in this study biofilm-forming actinobacteria were characterized on the basis of assessment their growth dynamics, larvicidal mortality and sublethal effects. Actinobacteria identification, biofilm growth and larvicidal bioactivities were performed by employing bacterial cultures, photomicrograph-based image analysis and bioassays. Bacterial morphotypes belong to Pseudonocardiaceae (PsA1TA) and Corynebacteriaceae (CoA2CA), which showed a distinctly substrate-dependent growth. PsA1TA microcolonies were randomly distributed on abdominal and thoracic membranous epicuticle. Afterwards, the thickness of mono-and bi-layered biofilms were increased fourfold the larval thoracoabdominal width (infectious breadth, 1010 μm - 1036 μm). In contrast, cephalic and anal sclerotized structures were radially encased by CoA2CA biofilms and increased threefold the size of both structures (infectious breadth, 1820 - 2030 μm y 1650 - 1860 μm, respectively). Although biofilms caused dissimilar mortality rates on the four larval instars, PsA1TA exerted highest larvicidal activity and virulence on second instar larvae (58 %-96 hours, LT50: 3.4 days) y CoA2CA on fourth instar larvae (85 %-96 hours, LT5G: 2.5 days). CoA2CA also induced incomplete release of pharate individuals as well as buckled protruding tarsi in newly emergent adults, whilst larval cadavers were overwhelmingly encased within massive biofilm aggregates. Biofilm-forming actinobacteria performed biolarvicidal activity and sublethal responses in A. aegypti.

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In Brazil, the Amazon region comprises 99.5% of the reported malaria cases. However, another hotspot of the disease is the Atlantic Forest regions, with the sporadic occurrence of autochthonous human cases. In such context, this study sought to investigate the role of anopheline mosquitoes (Diptera: Culicidae) in the residual malaria transmission in Atlantic Forest areas. Two rural areas in the Espírito Santo state were the surveyed sites. Mosquitoes were captured using Shannon trap and CDC light traps and identified into species based on morphological characters. Ecological indexes (Shannon-Wiener diversity, Simpson's dominance, Pielou equability, and Sorensen similarity) were the tools used in the anopheline fauna characterization and comparison along with the two explored areas. The assessment of the sampling adequacy in the studied areas was possible through the generation of a species accumulation curve. A correlation test verified the influence of climatic variables on the anopheline species abundance. A total of 1471 female anopheline mosquitoes were collected from May 2019 to April 2020, representing 13 species. The species richness was higher in Valsugana Velha (hypo-endemic) than in Alto Caparaó (non-endemic). There was a significant variation in the species abundance between Valsugana Velha (n = 1438) and Alto Caparaó (n = 33). The most abundant species was Anopheles (Kerteszia) cruzii complex Dyar and Knab, 1908 representing 87% of the total anophelines collected. These results suggest that the Plasmodium spp. circulation in Brazilian Atlantic Forest areas occurs mainly due to the high frequency of Anopheles (K.) cruzii complex, considered the principal vector of simian and human malaria in the region.

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Introduction: The vector-borne diseases program in México has an established network of ovitraps for entomological surveillance of Aedes spp. In response to reports of Aedes albopictus in the periphery of Mérida, the state capital of Yucatán, the Ministry of Health increased the specificity of this surveillance. Objective: To describe the presence and distribution of Ae. albopictus in Mérida and its relative abundance compared to Aedes aegypti in ovitraps of the vector control program. Materials and methods: During October, 2019, 91 ovitraps were randomly selected from 31 neighborhoods of Mérida. Mosquitoes were reared at the insectary of the Collaborative Unit for Entomological Bioassays of the Autonomous University of Yucatán from eggs collected in the field. Relative abundance was determined for adult individuals of each identified species and neighborhood. Results: 32 % of the neighborhoods were positive for Ae. albopictus and 100 % for Ae. aegypti. A total of 28 adults of Ae. albopictus (10 females and 18 males) were obtained from ovitraps. No correlation was observed between the abundance of Ae. aegypti and Ae. albopictus for both adults and females (p>0.05) at the neighborhood level. Conclusions: The results confirm that Ae. albopictus coexisted with Ae. aegypti in Mérida at the time of the study. The low relative abundance suggests that Ae. albopictus was in the initial phase of invasion.

Introducción. El programa de enfermedades transmitidas por vectores en México tiene una red establecida de ovitrampas para la vigilancia entomológica de Aedes spp. Los servicios de salud del estado de Yucatán, en respuesta a reportes de Aedes albopictus en la periferia de Mérida, capital del estado, incrementaron la especificidad de dicha vigilancia. Objetivo. Describir la presencia y distribución de Ae. albopictus en Mérida y su abundancia relativa comparada con Aedes aegypti, en ovitrampas del programa de control de vectores. Materiales y métodos. Durante octubre de 2019, se seleccionaron al azar 91 ovitrampas en 31 barrios de Mérida. Los mosquitos adultos se obtuvieron del insectario de la Unidad Colaborativa para Bioensayos Entomológicos de la Universidad Autónoma de Yucatán a partir de huevos recolectados en campo. Se determinó la abundancia relativa de individuos adultos de cada especie identificada y por barrios evaluados. Resultados. En el 32 % de los barrios muestreados, se detectó Ae. albopictus y, en todos ellos, Ae. aegypti. Se recolectaron 28 adultos de Ae. albopictus (10 hembras y 18 machos) en las ovitrampas. No se observó correlación entre la abundancia de adultos ni de hembras Ae. aegypti y Ae. albopictus por barrio (p>0,05). Conclusiones. Los resultados confirmaron que Ae. albopictus estaba coexistiendo con Ae. aegypti en Mérida en el momento del estudio. La baja abundancia relativa sugiere que Ae. albopictus se encontraba en la fase inicial de invasión.

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Resumen | Introducción. El programa de enfermedades transmitidas por vectores en México tiene una red establecida de ovitrampas para la vigilancia entomológica de Aedes spp. Los servicios de salud del estado de Yucatán, en respuesta a reportes de Aedes albopictus en la periferia de Mérida, capital del estado, incrementaron la especificidad de dicha vigilancia. Objetivo. Describir la presencia y distribución de Ae. albopictus en Mérida y su abundancia relativa comparada con Aedes aegypti, en ovitrampas del programa de control de vectores. Materiales y métodos. Durante octubre de 2019, se seleccionaron al azar 91 ovitrampas en 31 barrios de Mérida. Los mosquitos adultos se obtuvieron del insectario de la Unidad Colaborativa para Bioensayos Entomológicos de la Universidad Autónoma de Yucatán a partir de huevos recolectados en campo. Se determinó la abundancia relativa de individuos adultos de cada especie identificada y por barrios evaluados. Resultados. En el 32 % de los barrios muestreados, se detectó Ae. albopictus y, en todos ellos, Ae. aegypti. Se recolectaron 28 adultos de Ae. albopictus (10 hembras y 18 machos) en las ovitrampas. No se observó correlación entre la abundancia de adultos ni de hembras Ae. aegypti y Ae. albopictus por barrio (p>0,05). Conclusiones. Los resultados confirmaron que Ae. albopictus estaba coexistiendo con Ae.aegypti en Mérida en el momento del estudio. La baja abundancia relativa sugiere que Ae.albopictus se encontraba en la fase inicial de invasión.

Abstract | Introduction:The vector-borne diseases program in México has an established network of ovitraps for entomological surveillance of Aedes spp. In response to reports of Aedes albopictus in the periphery of Mérida, the state capital of Yucatán, the Ministry of Health increased the specificity of this surveillance. Objective: To describe the presence and distribution of Ae. albopictus in Mérida and its relative abundance compared to Aedesaegypti in ovitraps of the vector control program. Materials and methods: During October, 2019, 91 ovitraps were randomly selected from 31 neighborhoods of Mérida. Mosquitoes were reared at the insectary of the Collaborative Unit for Entomological Bioassays of the Autonomous University of Yucatán from eggs collected in the field. Relative abundance was determined for adult individuals of each identified species and neighborhood. Results: 32 % of the neighborhoods were positive for Ae. albopictus and 100 % for Ae. aegypti. A total of 28 adults of Ae. albopictus (10 females and 18 males) were obtained from ovitraps. No correlation was observed between the abundance of Ae. aegypti and Ae. albopictus for both adults and females (p>0.05) at the neighborhood level. Conclusions: The results confirm that Ae. albopictus coexisted with Ae. aegypti in Mérida at the time of the study. The low relative abundance suggests that Ae. albopictus was in the initial phase of invasion.

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Entomopathogenic agents are viable and effective options due to their selective action against insects but benign effects on humans and the environment. The most promising entomopathogens include subspecies of Bacillus thuringiensis (Bt), which are widely used for the biological control of insects, including mosquito vectors of human pathogens. The efficacy of B. thuringiensis toxicity has led to the search for new potentially toxic isolates in different regions of the world. Therefore, soil samples from the Amazon, Cerrado and Caatinga biomes of the state of Maranhão were evaluated for their potential larvicidal action against Aedes aegypti. The isolates with high toxicity to mosquito larvae, as detected by bioassays, were subjected to histological evaluation under a light microscope to identify the genes potentially responsible for the toxicity. Additionally, the toxic effects of these isolates on the intestinal epithelium were assessed. In the new B. thuringiensis isolates toxic to A. aegypti larvae, cry and cyt genes were amplified at different frequencies, with cry4, cyt1, cry32, cry10 and cry11 being the most frequent (33-55%) among those investigated. These genes encode specific proteins toxic to dipterans and may explain the severe morphological changes in the intestine of A. aegypti larvae caused by the toxins of the isolates.(AU)

Os agentes entomopatógenos são alternativas viáveis e eficazes, devido à sua ação seletiva para insetos sendo inofensivos ao homem e ao meio ambiente. Dentre os entomopatógenos mais promissores, destacam-se as subespécies de Bacillus thuringiensis (Bt) amplamente utilizadas no controle biológico de insetos incluindo espécies de mosquitos vetores de agentes patogênicos ao homem. A eficiência da toxicidade de Bt incentiva a prospecção de novos isolados em diversas regiões do mundo. Desta forma, em busca de novos isolados de B. thuringiensis potencialmente tóxicos, amostras de solo provenientes dos biomas Amazônia, Cerrado e Caatinga do estado do Maranhão foram avaliadas em relação ao seu potencial larvicida para Aedes aegypti. Os isolados que provocaram elevada toxicidade para larvas do mosquito, detectada por bioensaios, foram avaliados em relação aos potenciais genes responsáveis pela atividade tóxica, além da avaliação de efeitos tóxicos no epitélio intestinal através de análises histológicas em microscopia de luz. Os novos isolados de Bt tóxicos para larva de A. aegypti amplificaram frequências diferentes de genes cry e cyt sendo os mais frequentes (55-33%) os cry4, cyt1, cry32, cry10 e cry11 dentre os investigados. Esses genes codificam para proteínas tóxicas específicas para ordem Diptera, e podem explicar as severas alterações morfológicas provocadas pelas toxinas dos isolados observadas no intestino das larvas de A. aegypti.(AU)

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Abstract Entomopathogenic agents are viable and effective options due to their selective action against insects but benign effects on humans and the environment. The most promising entomopathogens include subspecies of Bacillus thuringiensis (Bt), which are widely used for the biological control of insects, including mosquito vectors of human pathogens. The efficacy of B. thuringiensis toxicity has led to the search for new potentially toxic isolates in different regions of the world. Therefore, soil samples from the Amazon, Cerrado and Caatinga biomes of the state of Maranhão were evaluated for their potential larvicidal action against Aedes aegypti. The isolates with high toxicity to mosquito larvae, as detected by bioassays, were subjected to histological evaluation under a light microscope to identify the genes potentially responsible for the toxicity. Additionally, the toxic effects of these isolates on the intestinal epithelium were assessed. In the new B. thuringiensis isolates toxic to A. aegypti larvae, cry and cyt genes were amplified at different frequencies, with cry4, cyt1, cry32, cry10 and cry11 being the most frequent (33-55%) among those investigated. These genes encode specific proteins toxic to dipterans and may explain the severe morphological changes in the intestine of A. aegypti larvae caused by the toxins of the isolates.

Resumo Os agentes entomopatógenos são alternativas viáveis e eficazes, devido à sua ação seletiva para insetos sendo inofensivos ao homem e ao meio ambiente. Dentre os entomopatógenos mais promissores, destacam-se as subespécies de Bacillus thuringiensis (Bt) amplamente utilizadas no controle biológico de insetos incluindo espécies de mosquitos vetores de agentes patogênicos ao homem. A eficiência da toxicidade de Bt incentiva a prospecção de novos isolados em diversas regiões do mundo. Desta forma, em busca de novos isolados de B. thuringiensis potencialmente tóxicos, amostras de solo provenientes dos biomas Amazônia, Cerrado e Caatinga do estado do Maranhão foram avaliadas em relação ao seu potencial larvicida para Aedes aegypti. Os isolados que provocaram elevada toxicidade para larvas do mosquito, detectada por bioensaios, foram avaliados em relação aos potenciais genes responsáveis pela atividade tóxica, além da avaliação de efeitos tóxicos no epitélio intestinal através de análises histológicas em microscopia de luz. Os novos isolados de Bt tóxicos para larva de A. aegypti amplificaram frequências diferentes de genes cry e cyt sendo os mais frequentes (55-33%) os cry4, cyt1, cry32, cry10 e cry11 dentre os investigados. Esses genes codificam para proteínas tóxicas específicas para ordem Diptera, e podem explicar as severas alterações morfológicas provocadas pelas toxinas dos isolados observadas no intestino das larvas de A. aegypti.

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Vector competence refers to the ability of a vector to acquire, maintain, and transmit a pathogen. Collecting mosquito saliva in medium-filled capillary tubes has become the standard for approximating arbovirus transmission. However, this method is time-consuming and labor-intensive. Here we compare the capillary tube method to an alternative high-throughput detection method the collection of saliva on paper cards saturated with honey, with (FTA card) and without (filter paper) reagents for the preservation of nucleic acid for Aedes aegypti and Aedes albopictus mosquitoes infected with two emerging genotypes of the chikungunya virus (CHIKV). Model results showed that the Asian genotype CHIKV dissemination in the harvested legs of both Ae. aegypti and Ae. albopictus increased the odds of females having a positive salivary infection and higher salivary viral titers, while for the IOL genotype the same effect was observed only for Ae. aegypti. Of the three tested detection methods, the FTA card was significantly more effective at detecting infected saliva of Ae. aegypti and Ae. albopictus females than the capillary tube and filter paper was as effective as the capillary tube for the Asian genotype. We did not find significant effects of the detection method in detecting higher viral titer for both Asian and IOL genotypes. Our results are discussed in light of the limitations of the different tested detection methods.

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BACKGROUND: In Brazil and several countries in the Americas, where dengue, chikungunya and Zika are cocirculating, there is a need to understand how different mosquito species relate to landscape and humans. Mosquito ecology and distribution, especially at finer spatial scales, are key factors to study since the relationship of mosquito communities to their habitats might have important consequences in the risk of disease transmission to humans. The aim of this study was to evaluate the diversity of resident culicids along heterogeneous landscapes in different endemic cities for dengue, chikungunya and Zika. METHODS: Fourteen collection sites were randomly selected in six landscapes characterized as urban, periurban and rural along two endemic metropolitan cities in Rio de Janeiro, Brazil: Itaboraí and Cachoeiras de Macacu, Rio de Janeiro. In each site, adult mosquito collections were performed using different traps and backpack aspiration. Collections took place during the rainy and dry seasons of 2015 and 2016. To measure diversity in each landscape, we generated species accumulation curves and used different indexes: rarefied species richness, Chao1-bc and ACE-1. Mosquito habitat segregation along different land use types was measured with a partial canonical correspondence analysis (pCCA). Generalized linear mixed models (GLMM) were used to model the probability of occurrence of the most abundant species along an Urban-Forest gradient. RESULTS: A total of 13,462 adult mosquitoes from 10 genera and 41 species were collected. The most abundant species were Culex quinquefasciatus Say, 1823, Aedes aegypti (Linnaeus, 1762) and Aedes albopictus (Skuse, 1895). There was a significant association between rarefied species richness and landscape, with higher richness in the Rural landscape. The number of observed species was matched only in the Urban landscape. Most species showed segregation along an Urban-Forest gradient, and the great majority were associated with forested habitats. We were able to fit prediction models for six mosquito species. DISCUSSION: The paper discusses the impact of human activities on landscape and its effects on mosquito populations, focusing on the segregation of different known vector species and their proximity to human altered environments. Most of these species are known arbovirus vectors and knowledge of their distribution are key elements that health authorities should take into account when planning arbovirus surveillance and vector control activities.

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OBJECTIVE: To identify studies on the competence of Culex mosquitoes as vectors for the transmission of Zika virus (ZIKV) around the globe. METHODS: We performed an integrative review to identify relevant articles on specific experiments to determine whether Culex mosquitoes are vectors for ZIKV. The sources we used for our research were the Brazilian Periódicos CAPES electronic portal (MEDLINE/PubMed, ScienceDirect Journals, Nature Publishing Group, SciELO, Springer Link, and 250 other databases) and gray literature. RESULTS: We identified 344 studies, of which 36 were considered for this review. In 8 studies, infection in salivary glands of Culex quinquefasciatus, Culex restuans, Culex tarsalis, and Culex coronator was detected. Cx. quinquefasciatus was the most studied among those confirmed as potential ZIKV vectors, and only strains of Asian lineages (THA/2014/SV0127-14; SZ01 (2016)) and American lineages (BRPE243 (2015); PRVABC59 (2015)) can infect the salivary glands of Culex mosquitoes. The tested African strains (MR766 and DAK AR 41525) were unable to infect salivary glands. CONCLUSIONS: There is still a lack of compelling evidence that indicates Culex spp. are a competent ZIKV vector, but they should remain a target for further monitoring studies, especially regarding ZIKV transmission to other species. Furthermore, studies should not be limited to studying whether their salivary glands are infected.