[First record of Aedes albopictus in Galicia, obtained by citizen science through Mosquito Alert]. / Primera cita de Aedes albopictus para Galicia, obtenida mediante ciencia ciudadana por Mosquito Alert.

The first detection of the tiger mosquito, Aedes (Stegomyia) albopictus (Skuse, 1894), in the autonomous community of Galicia (Spain) is reported. The finding has been possible thanks to the collaboration between citizens, the citizen science application Mosquito Alert and the Rede Galega de Vixilancia de Vectores (ReGaViVec). At the beginning of August 2023, a same person submitted through the app several reports consistent with the tiger mosquito in the municipality of Moaña, in Pontevedra. The ReGaViVec entomological team confirmed the species and conducted vector surveillance in the area by placing traps (11 ovitraps and 3 BG-Sentinel 2 with BG-Lure attractant) with a weekly collection frequency. This finding represents the most northwestern detection of the tiger mosquito in the Iberian Peninsula and shows the crucial role of citizen science in vector surveillance.

Japanese Encephalitis can be devastating.

Abstract: Japanese encephalitis, caused by the JE virus transmitted by mosquitoes, is the most common type of epidemic encephalitis in Asia. It is endemic in most of South and Southeast Asia, but the number of cases can vary greatly between areas. While many infections do not lead to disease, the symptomatic cases can be very severe and life-threatening. It mainly affects children, whereas adults are generally immune to the disease due to either being infected in childhood or receiving vaccination. However, individuals who are not immune, such as travelers from non-endemic countries, are susceptible to the disease when exposed to the virus for the first time, regardless of age. Without antiviral treatment options, vaccination is the only strategy to establish effective protection against Japanese encephalitis.

A virus becomes a global concern: research activities on West-Nile virus.

Currently, West-Nile virus (WNV) is spreading worldwide to colder regions due to climate change. Human mortality and morbidity are prevalent and steadily increasing, associated with costs to public health systems. Therefore, the question of the impact of scientific engagement arises. What trends, barriers, and incentives for research related to global burdens are important in this context? To answer these questions, this study provides detailed insights into the publication patterns of WNV research and interprets them using several parameters, such as absolute and relative publication indices and socioeconomic and epidemiological characteristics. It is shown that national interests combined with regional outbreaks significantly influence publication intensity. Thus, a correlation between national publication volume and the number of WNV cases was observed. In contrast to most life science topics, the scientific interest in WNV significantly decreased after 2006. The USA, as the main actor in WNV research, is at the centre of international networking. Recently, European countries are also getting involved according to their new-emerging outbreaks. The results demonstrate national interest in research activities with a lack of globally focused approaches that are urgently needed to better understand and assess the distribution and characteristics of WNV.

Future land-use change predictions using Dyna-Clue to support mosquito-borne disease risk assessment.

Mosquitoes are known vectors for viral diseases in Canada, and their distribution is driven by climate and land use. Despite that, future land-use changes have not yet been used as a driver in mosquito distribution models in North America. In this paper, we developed land-use change projections designed to address mosquito-borne disease (MBD) prediction in a 38 761 km2 area of Eastern Ontario. The landscape in the study area is marked by urbanization and intensive agriculture and hosts a diverse mosquito community. The Dyna-CLUE model was used to project land-use for three time horizons (2030, 2050, and 2070) based on historical trends (from 2014 to 2020) for water, forest, agriculture, and urban land uses. Five scenarios were generated to reflect urbanization, agricultural expansion, and natural areas. An ensemble of thirty simulations per scenario was run to account for land-use conversion uncertainty. The simulation closest to the average map generated was selected to represent the scenario. A concordance matrix generated using map pair analysis showed a good agreement between the simulated 2020 maps and 2020 observed map. By 2050, the most significant changes are predicted to occur mainly in the southeastern region's rural and forested areas. By 2070, high deforestation is expected in the central west. These results will be integrated into risk models predicting mosquito distribution to study the possibility of humans' increased exposure risk to MBDs.

The oral repellent - science fiction or common sense? Insects, vector-borne diseases, failing strategies, and a bold proposition.

Over the last decades, unimaginable amounts of money have gone into research and development of vector control measures, repellents, treatment, and vaccines for vector borne diseases. Technological progress and scientific breakthroughs allowed for ever more sophisticated and futuristic strategies. Yet, each year, millions of people still die or suffer from potentially serious consequences of malaria or dengue to more recent infections, such as zika or chikungunya, or of debilitating consequences of neglected tropical diseases. This does not seem value for money. In addition, all current vector control strategies and personal protection methods have shortcomings, some serious, that are either destructive to non-target species or unsatisfactory in their effectiveness. On the other hand, the rapid decline in insect populations and their predators reflects decades-long aggressive and indiscriminate vector control. This major disruption of biodiversity has an impact on human life not anticipated by the well-meaning killing of invertebrates. The objective of this paper is to re-examine current control methods, their effectiveness, their impact on biodiversity, human and animal health, and to call for scientific courage in the pursuit of fresh ideas. This paper brings together topics that are usually presented in isolation, thereby missing important links that offer potential solutions to long-standing problems in global health. First, it serves as a reminder of the importance of insects to human life and discusses the few that play a role in transmitting disease. Next, it examines critically the many currently employed vector control strategies and personal protection methods. Finally, based on new insights into insect chemo-sensation and attractants, this perspective makes a case for revisiting a previously abandoned idea, the oral repellent, and its use via currently successful methods of mass-application. The call is out for focused research to provide a powerful tool for public health, tropical medicine, and travel medicine.

Caracterización de los focos de mosquitos Aedes aegypti en el municipio de Abreus. 2016-2022

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.

Infecciones por Wolbachia pipientis en poblaciones de Aedes albopictus en la ciudad de València (España): implicaciones para el control de mosquitos / Wolbachia pipientis infections in populations of Aedes albopictus in the city of València (Spain): implications for mosquito control

Fundamentos: La presencia deAedes albopictus, de alto impacto sanitario y social, se informó por primera vez en Valenciaen 2015. Las herramientas innovadoras para su control incluyen el uso de la bacteria endosimbióticaWolbachia pipientis. La liberación de mosquitos machos infectados con la cepawPip ha demostrado ser muy prometedora para aplicar la Técnica de InsectosIncompatibles (IIT) a gran escala. Antes de que esta estrategia pueda implementarse, es importante saber si las poblaciones localesde mosquitos silvestres están infectadas porWolbachia y, de ser así, identificar las cepas/supergrupos infectantes, siendo estos losobjetivos del presente trabajo. Métodos: Se recolectaron huevos de los diecinueve distritos de València entre mayo y octubre de 2019, y se mantuvieron en ellaboratorio hasta llegar a adultos. Un total de cincuenta individuos adultos deAe. albopictus fueron procesados y analizados paradetectar la presencia deWolbachia y su caracterización molecular. Estas acciones se enmarcaron en la colaboración establecida conla Concejalía de Salud y Consumo del Ayuntamiento de València. La prueba exacta de Fisher fue utilizada para detectar la significaciónestadística de las diferencias entre grupos. Resultados: El 94% de las muestras analizadas estaban infectadas de forma natural conWolbachia. Se identificaron los supergruposwAlbA ywAlbB, y la mayoría de las muestras (72% de las infectadas) presentaban coinfecciones. Conclusiones: Los datos proporcionan la primera caracterización de la presencia deWolbachia en poblaciones naturales deAe. albopictus en el área mediterránea de España. Esta información es relevante para evaluar el potencial uso de cepas deWolbachiade cara a la supresión de poblaciones de mosquito tigre asiático mediante la liberación masiva de machos infectados artificialmente.(AU)

Background: The presence ofAedes albopictus, of high sanitary and social impact, was first reported in Valencia (Eastern Spain)in 2015. Innovative tools for its control include the use of the endosymbiotic bacteriumWolbachia pipientis. The release of mosquitomales infected with thewPip strain, has proven very promising for large-scale Incompatible Insect Technique (IIT) applications. Beforethis strategy can be implemented in Valencia, it is important to know whether the natural local mosquito populations areWolbachia-infected and, if so, identifying the infecting strains/supergroups, these being the objectives of the present work. Methods: Eggs were collected from the 19 districts of the València city between May and October 2019. A total of 50 lab-reared adultAe. albopictus individuals were processed and analyzed forWolbachia detection and molecular characterization. These actions tookplace within the framework of a collaboration established with the Department of Health and Consumer Affairs of the city council ofValencia. Fisher’s exact test was used to detect the statistical significance of the differences between groups. Results: Our study revealed that 94% of the analyzed samples were naturally infected withWolbachia. BothwAlbA andwAlbBsupergroups were identified, with most samples (72% of the infected ones) carrying co-infections. Conclusions: These data provide the first characterization of theWolbachia presence in natural populations ofAe. albopictusin the Mediterranean area of Spain. This information is relevant to evaluate the potential use ofWolbachia strains in order to achievethe suppression of the Asian tiger mosquito populations through massive release of artificially-infected males.(AU)

A Brief History of the Discovery of RNA-Mediated Antiviral Immune Defenses in Vector Mosquitos.

Arthropod-borne viruses (arboviruses) persist in a natural cycle that includes infections of humans or other vertebrates and transmission between vertebrates by infected arthropods, most commonly mosquitos. Arboviruses can cause serious, sometimes fatal diseases in humans and other vertebrates but cause little pathology in their mosquito vectors. Knowledge of the interactions between mosquito vectors and the arboviruses that they transmit is an important facet of developing schemes to control transmission. Mosquito innate immune responses to virus infection modulate virus replication in the vector, and understanding the components and mechanisms of the immune response could lead to improved methods for interrupting the transmission cycle. The most important aspect of mosquito antiviral defense is the exogenous small interfering RNA (exo-siRNA) pathway, one arm of the RNA interference (RNAi) silencing response. Our research as well as that of many other groups over the past 25 years to define this pathway are reviewed here. A more recently recognized but less well-understood RNA-mediated mosquito defense against arbovirus infections, the PIWI-interacting RNA (piRNA) pathway, is also described.

A coleção de mosquitos de Antonio Gonçalves Peryassú do Museu Nacional, Rio de Janeiro: registro de memória de um patrimônio desaparecido / The Antonio Gonçalves Peryassú mosquito collection at the Museu Nacional, in Rio de Janeiro: retrieving the memory of lost heritage

Resumo As coleções e pesquisas feitas nas primeiras décadas do século XX, no Rio de Janeiro, foram fundamentais para o estudo da sistemática e da história natural dos mosquitos no Brasil. Um personagem de destaque nesse cenário foi Antonio Gonçalves Peryassú. Analisamos o histórico de uma coleção por ele organizada no Museu Nacional do Rio de Janeiro, entre 1918 e 1922.

Abstract Collections formed and studies conducted in the early decades of the twentieth century in Rio de Janeiro, Brazil, were crucial for the study of the systematization and natural history of mosquitoes in Brazil. One key figure in this context was Antonio Gonçalves Peryassú. The history of a collection he organized at Museu Nacional [National Museum] in Rio de Janeiro between 1918 and 1922 is analyzed.

Dengue más allá del trópico: estudio de series temporales 2015-2016 versus 2019-2020 en un hospital pediátrico de la Ciudad de Buenos Aires / Dengue beyond the tropics: a time-series study comprising 2015-2016 versus 2019-2020 at a children's hospital in the City of Buenos Aires

Introducción. El dengue es un problema de salud pública a nivel mundial. Confinado en sus orígenes a las zonas tropicales y subtropicales, en la actualidad se presenta en otras regiones como Argentina. Desde el año 2008 se presenta con brotes epidémicos en la Ciudad Autónoma de Buenos Aires, con escasos reportes en niños. Objetivo. Analizar y comparar las características clínicas, epidemiológicas, de laboratorio y evolutivas de los dos últimos brotes de dengue fuera del área endémica. Población y métodos. Estudio de series temporales. Se incluyeron pacientes menores de 18 años con dengue probable o confirmado, evaluados en un hospital pediátrico de la Ciudad de Buenos Aires durante los períodos 2015-2016 y 2019-2020. Resultados. Se incluyeron 239 pacientes, 29 (12 %) con antecedente de viaje. La mediana de edad fue de 132 meses (rango intercuartílico: 102-156). Todos tuvieron fiebre. Otros síntomas fueron: cefalea en 170 (71 %), mialgias en 129 (54 %) y exantema en 122 (51 %). Cuarenta pacientes (17 %) tenían comorbilidades. Presentaron signos de alarma 79 pacientes (33 %) y 14 (6 %) tenían dengue grave. Requirieron internación 115 pacientes (45 %) y ninguno falleció. El serotipo DENV-1 fue el más frecuente. El antecedente de viaje y la necesidad de internación predominaron en el primer período; el dengue grave y la infección previa, en el segundo. Conclusiones. Ningún paciente falleció de dengue en los períodos estudiados. Se observaron diferencias estadísticamente significativas en la frecuencia de internación; el antecedente de viaje fue más frecuente en el período 2015-2016 y el dengue grave, en el 2019-2020.

Introduction. Dengue is a public health problem worldwide. It was originally confined to tropical and subtropical areas, but it is now present in other regions, such as Argentina. Epidemic outbreaks have been observed in the City of Buenos Aires since 2008, with few reports in children. Objective. To analyze and compare the clinical, epidemiological, laboratory, and evolutionary characteristics of the latest 2 dengue outbreaks outside the endemic area. Population and methods. Time-series study. Patients under 18 years of age with probable or confirmed dengue and evaluated in a children's hospital of the City of Buenos Aires during the periods 2015-2016 and 2019-2020 were included. Results. A total of 239 patients were included; 29 (12%) had a history of travel. Their median age was 132 months (interquartile range: 102156). All had a fever. Other symptoms included headache in 170 (71%), myalgia in 129 (54%), and rash in 122 (51%). Forty patients (17%) had comorbidities. Warning signs were observed in 79 patients (33%); 14 (6%) developed severe dengue; 115 (45%) were hospitalized; none died. DENV-1 was the most common serotype. A history of travel and hospitalization prevailed in the first period; severe dengue and prior infection, in the second period. Conclusions. No patient died due to dengue in either study period. Statistically significant differences were observed in the frequency of hospitalization; a history of travel was more common in the 2015-2016 period and severe dengue, in the 2019-2020 period.

Diversity and distribution of mosquitoes (Diptera: Culicidae) in Peru and their relationship with metaxenic diseases / Diversidad y distribución de mosquitos (Diptera: Culicidae) en el Perú y su relación con las enfermedades metaxénicas

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.

Efectos de la competencia larvaria intraespecífica de Aedes aegypti y Aedes albopictus en condiciones de laboratorio / Effects of intraspecific larval competence of Aedes aegypti and Aedes albopictus under laboratory conditions

RESUMEN Introducción: Aedes aegypti y Aedes albopictus constituyen dos de las especies más importantes de mosquitos, debido a que son vectores primarios de enfermedades emergentes y reemergentes que representan una amenaza significativa para la salud pública. Objetivo: Evaluar el efecto de la competencia larvaria intraespecífica causada por baja y alta densidad de dos poblaciones de Ae. aegypti y Ae. albopictus sobre aspectos de su ciclo de vida en condiciones de laboratorio. Métodos: Se utilizaron dos poblaciones de mosquitos, Ae. aegypti y Ae. albopictus, ambas colectadas en estado de larva en el Reparto Juan de Dios Fraga, La Lisa, La Habana, Cuba. Se establecieron condiciones de baja (70 larvas) y alta densidad larvaria (140 larvas) en cada réplica para cada una de las especies. Se emplearon larvas desde el primer estadio, que se siguieron hasta la formación de los adultos. Se evaluaron las variables duración del ciclo larvario, supervivencia larvaria, así como talla y supervivencia de hembras adultas, respectivamente. Resultados: Se encontró que las variables evaluadas no se afectaron en condiciones de baja densidad larvaria. Sin embargo, el efecto de la relación larvaria intraespecífica bajo condiciones de alta densidad presentada en los hábitats de Ae. aegypti y Ae. albopictus tuvo un efecto negativo en cada una de las variables del ciclo de vida evaluadas. Conclusiones: Estas alteraciones observadas son importantes dentro de los componentes de la capacidad vectorial, con implicaciones en la epidemiología de las enfermedades transmitidas por estos mosquitos. Los resultados pudieran extrapolarse al comportamiento de estos mosquitos en su entorno natural. Estas condiciones podrían aumentar los patrones de transmisión del virus del dengue, así como un mayor riesgo de infección para la población humana.

ABSTRACT Introduction: Aedes aegypti and Aedes albopictus are two of the most important mosquito species, since they are the main vector of emerging and re-emerging diseases that represent a significant threat to public health. Objective: To evaluate the effect of intraspecific larval competence caused by low and high density in two populations of Ae. aegypti and Ae. albopictus on aspects of their life cycles under laboratory conditions. Methods: Two mosquitos populations were used, Ae. aegypti and Ae. albopictus, both collected during their larval stage in Juan de Dios Fraga town, La Lisa, Havana, Cuba. Low (70 larvae) and high (140 larvae) density conditions were established in each replication for each species. Larvae from the first stage were used and follow-up was established until adults emerged. Variables such as: larval cycle duration, larval survival, and adult female size and survival were evaluated. Results: The variables evaluated were not affected under low larval density conditions. However, the intraspecific larval relationship under high density conditions in Ae. aegypti and Ae. albopictus habitats had a negative effect in each of the variables of the life cycles. Conclusions: The observed alterations are important within the components of vectorial capacity, with implications for the epidemiology of these mosquitos-borne diseases. The results could be extended to the behavior of these mosquitoes in their natural environment. These conditions could increase the transmission patterns of dengue virus and the risk of infection for the human population.

Bacillus thuringiensis A21, un aislado no tóxico de elevada actividad larvicida residual contra Aedes aegypti / Bacillus thuringiensis A21, a non-toxic isolate of high residual larvicidal activity against Aedes aegypti

Introducción: Los productos derivados de Bacillus thuringiensis se han empleado con éxito en el control de insectos. Sin embargo, la poca residualidad promueve la búsqueda de alternativas. En Cuba diferentes estudios informan la evaluación y selección de aislamientos de B. thuringiensis con actividad larvicida contra Aedes aegypti: el aislado A21 se destaca por su elevada actividad larvicida y ausencia de betaexotoxina. Objetivo: Evaluar la toxicidad/patogenicidad aguda oral y actividad larvicida residual del aislado A21. Métodos: La evaluación de la toxicidad/patogenicidad aguda oral del aislado A21 se estableció en el modelo biológico Rattus norvegicus. Se realizaron observaciones clínicas diarias de los animales y se evaluó el peso corporal. Se estimó la eliminación y la infectividad de B. thuringiensis mediante análisis de muestras de heces, y de fluidos y órganos, respectivamente. Para determinar la actividad larvicida residual del aislado A21 frente a larvas de Ae. aegypti se realizaron bioensayos con diferentes volúmenes de recambios de agua semanal (total, parcial, no recambio) en los recipientes. La mortalidad obtenida se calculó a las 24-72 h. Resultados: Con el aislado A21 no se detectó toxicidad/patogenicidad aguda oral en Rattus norvegicus. En el estudio de residualidad, la mortalidad larvaria a las 72 h se mantuvo elevada (80-100 por ciento) hasta la semana 24. A partir de la semana 25 la mortalidad larvaria disminuyó (p < 0,05). Conclusiones: Se evidencia la baja toxicidad y la elevada actividad larvicida residual del aislado A21 contra Ae. aegypti y lo convierten en un candidato promisorio para el desarrollo de biolarvicidas. Estos productos biológicos podrían contribuir a mejorar las estrategias de control del vector existentes en Cuba(AU)

ABSTRACT Introduction: Bacillus thuringiensis-based products have been successfully used for insect control. However, their low residuality promotes the search for alternatives. In Cuba, different studies have informed about the evaluation and selection of B. thuringiensis isolates with larvicidal activity against Aedes aegypti: isolate A21 highlights for its high larvicidal activity and absence of beta-exotoxins. Objective: To evaluate the acute oral toxicity/pathogenicity and the residual larvicidal activity of isolate A21. Methods: The evaluation of the acute oral toxicity/pathogenicity of isolate A21 was established in the animal model Rattus norvegicus. Daily clinical observations of the animals were carried out, and their body weight was evaluated. The elimination and infectivity of B. thuringiensis were estimated by analyzing feces, and fluids and organs samples, respectively. To determine the residual larvicidal activity of isolate A21 to Ae. aegypti larvae, bioassays were conducted with different volumes of weekly water changes (total, partial, no change) in the containers. Mortality was calculated at 24h-72h. Results: No acute oral toxicity/pathogenicity was detected with isolate A21 in Rattus norvegicus. In the study of residuality, at 72h larval mortality remained high (80 percent-100%) until week 24, decreasing from week 25 (p < 0.05). Conclusions: It is evidenced the low toxicity and high residual larvicidal activity of isolate A21 against Ae. aegypti, which makes it a promising candidate for the development of biolarvicides. These biological products could contribute to the improvements of the existing vector control strategies in Cuba(AU)

Diversidad genética de aedes aegypti en el eje transfronterizo Central-Alto Paraná en Paraguay / Genetic diversity of Aedes aegypti in the central-upper Paraná Cross-Border axis in Paraguay

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.

Rapid Differential Detection of Japanese Encephalitis Virus and Getah Virus in Pigs or Mosquitos by a Duplex TaqMan Real-Time RT-PCR Assay.

Both JEV (Japanese encephalitis virus) and GETV (Getah virus) pose huge threats to the safety of animals and public health. Pigs and mosquitoes play a primary role in JEV and GETV transmission. However, there is no way to quickly distinguish between JEV and GETV. In this study, we established a one-step duplex TaqMan RT-qPCR for rapid identification and detection of JEV and GETV. Primers and probes located in the NS1 gene of JEV and the E2 gene of GETV that could specifically distinguish JEV from GETV were selected for duplex TaqMan RT-qPCR. In duplex real-time RT-qPCR detection, the correlation coefficients (R2) of the two viruses were higher than 0.999. The RT-qPCR assay demonstrated high sensitivity, extreme specificity, and excellent repeatability. Detection of JEV and GETV in field mosquito and pig samples was 100 times and 10 times more sensitive than using traditional PCR, respectively. In addition, the new test took less time and could be completed in under an hour. Clinical sample testing revealed the prevalence of JEV and GETV in mosquitoes and pig herds in China. This complete duplex TaqMan RT-qPCR assay provided a fast, efficient, specific, and sensitive tool for the detection and differentiation of JEV and GETV.

Invertebrates for vertebrate biodiversity monitoring: Comparisons using three insect taxa as iDNA samplers.

Metabarcoding of environmental DNA (eDNA) is now widely used to build diversity profiles from DNA that has been shed by species into the environment. There is substantial interest in the expansion of eDNA approaches for improved detection of terrestrial vertebrates using invertebrate-derived DNA (iDNA) in which hematophagous, sarcophagous, and coprophagous invertebrates sample vertebrate blood, carrion, or faeces. Here, we used metabarcoding and multiple iDNA samplers (carrion flies, sandflies, and mosquitos) collected from 39 forested sites in the southern Amazon to profile gamma and alpha diversity. Our main objectives were to (1) compare diversity found with iDNA to camera trapping, which is the conventional method of vertebrate diversity surveillance; and (2) compare each of the iDNA samplers to assess the effectiveness, efficiency, and potential biases associated with each sampler. In total, we collected and analysed 1759 carrion flies, 48,686 sandflies, and 4776 mosquitos. Carrion flies revealed the greatest total vertebrate species richness at the landscape level, despite the least amount of sampling effort and the fewest number of individuals captured for metabarcoding, followed by sandflies. Camera traps had the highest median species richness at the site-level but showed strong bias towards carnivore and ungulate species and missed much of the diversity described by iDNA methods. Mosquitos showed a strong feeding preference for humans as did sandflies for armadillos, thus presenting potential utility to further study related to host-vector interactions.

Investigação de correlação entre frequência de batimento e tamanho alar de Aedes aegypti (Linnaeus, 1976)

Differences in the ecological role within populations can generate morphological variations triggered by selective pressures that act differently in each sex, thus causing possible variations that may indicate sexual dimorphism in wing size, as well as wing beat frequency. Knowing this, the objective of the present study was to investigate whether there is a correlation between the variables of beat frequency and wing size in Aedes aegypti. For this purpose, mosquitoes with 4 to 5 days of emergence were used, placed individually in collectors, and arranged in incubators, maintaining the environmental conditions of 26°C, 60-75% RH and photoperiod of 14:10h (L:D), separated by sex. In order to obtain individuals of different sizes (large and small females and males), experimental colony was divided into two larval densities: low (50 larvae/breeding place), which generated large mosquitoes, and high (200 larvae/breeding place), which generated the small mosquitoes. After collecting alar beat frequency data, individuals were stored in microtubes containing 70% alcohol. Then, the wings were detached, mounted, photographed and digitized and centroid size analyzes were performed. Finally, correlation analyzes (Pearson) were developed. As a result, in this work, it can be confirmed that there is sexual dimorphism of the wingbeat frequency in Ae. aegypti, demonstrated by the mean frequency (large females = 531.4 x large males = 767 Hz; small females = 537.7 x small males = 721.3 Hz). Furthermore, a small difference was also observed between the frequency of wingbeats within the same sex, with smaller individuals (females and small males) having higher and lower wingbeat frequencies, respectively, when compared to larger individuals (females and males). Wing size sexual dimorphism can also be confirmed in Ae. aegypti, as well as variation within the same sex, depending on the population density applied during rearing under laboratory conditions, with large females and males having a significantly larger wing centroid than small females and males. Finally, the correlations between the beat frequency and wing size variables performed in this study showed us that large females and small males of Ae. aegypti have no correlation between wingbeat frequency and wing size. While small females showed a significant but low and negative correlation; and large males showed a significant but low and positive correlation, that is, the larger the wing size (and consequently their body), the lower their wing beat frequency.

As diferenças no papel ecológico dentro das populações podem gerar variações morfológicas desencadeadas por pressões seletivas que atuam de forma diferente em cada sexo, causando assim possíveis variações que podem indicar dimorfismo sexual de tamanho alar, bem como de frequência de batimento alar. Sabendo disso, o objetivo do presente estudo foi investigar se há correlação entre as variáveis de frequência de batimento e tamanho alar em Aedes aegypti. Para tanto foram utilizados mosquitos de 4 a 5 dias de emergência, alocados individualmente em coletores, e dispostos em incubadoras mantendo-se as condições ambientais de 26°C, 60-75% UR e fotoperíodo de 14:10h (C:E), separados por sexo. Para a obtenção de indivíduos de tamanhos divergentes (fêmeas grandes e pequenas, machos grandes e pequenos), a colônia experimental foi dividida em duas densidades larvais: baixa (50 larvas/criadouro), que geraram os mosquitos grandes; e alta (200 larvas/criadouro), que geraram os mosquitos pequenos. Após a coleta de dados de frequência de batimento alar, os indivíduos foram armazenados em microtubos contendo álcool 70%. Em seguida, as asas foram destacadas, montadas, fotografadas e digitalizadas e análises de tamanho do centroide foram realizadas. Por fim, análises de correlação (Pearson) foram desenvolvidas. Como resultados, neste trabalho, pode-se confirmar que existe dimorfismo sexual da frequência de batimento alar em Ae. aegypti, sendo demonstrado pela média da frequência (fêmeas grandes = 531,4 x machos grandes = 767 Hz; fêmeas pequenas = 537,7 x machos pequenos = 721,3 Hz). Ademais, foi observada também uma pequena diferença entre a frequência de batimento alar dentro do mesmo sexo, sendo que os indivíduos menores (fêmeas e machos pequenos) apresentaram frequência de batimento alar maior e menor, respectivamente, quando comparados com os indivíduos maiores (fêmeas e machos grandes). Pode-se confirmar também dimorfismo sexual de tamanho alar em Ae. aegypti, bem como variação dentro do mesmo sexo, a depender da densidade populacional aplicada durante a criação em condições laboratoriais, sendo que fêmeas e machos grandes possuem o tamanho do centroide alar significativamente maior que fêmeas e machos pequenos. Por fim, as correlações entre as variáveis de frequência de batimento e tamanho alar realizadas neste trabalho nos mostraram que fêmeas grandes, e machos pequenos de Ae. aegypti não possuem correlação entre frequência de batimento alar e tamanho alar. Enquanto que fêmeas pequenas apresentaram correlação significativa, porém baixa, e negativa; e machos grandes apresentaram uma correlação significativa, porém baixa, e positiva, ou seja, quanto maior o tamanho alar (e consequentemente seu corpo), menor foi sua frequência de batimento alar.

Intervenciones genéticas de Aedes aegypti para el control de arbovirosis / Genetic interventions of Aedes aegypti for the control of arboviruses

La ineficacia de las estrategias actuales para el control químico de los mosquitos vectores plantea la necesidad de desarrollar enfoques novedosos, entre estos están las estrategias genéticas para reducir las poblaciones de mosquitos vectores o sustituirlos por aquellos que no son capaces de transmitir patógenos, esto se logra a través de herramientas moleculares que permiten la manipulación y transgénesis de genes. Las secuencias del genoma de los mosquitos y las bases de datos de marcadores de secuencias expresadas asociadas permiten investigaciones a gran escala para proporcionar nuevos conocimientos sobre las vías evolutivas, bioquímicas, genéticas, metabólicas y fisiológicas. Además, la genómica comparativa revela las bases de los mecanismos evolutivos con especial atención a las interacciones específicas entre vectores y patógenos. Se ha desarrollado tecnología de transgénesis para el mosquito de la fiebre amarilla y dengue, Aedes aegypti. Se ha logrado integración exitosa de ADN exógeno en la línea germinal de este mosquito con los elementos transponibles. La disponibilidad de múltiples elementos y genes marcadores proporciona un poderoso conjunto de herramientas para investigar las propiedades biológicas básicas de este insecto vector, así como los materiales para desarrollar nuevas estrategias de control genético de poblaciones de mosquitos basadas en la técnica del insecto estéril. Una de estas estrategias consiste en liberar a la población machos esterilizados por radiación; otro, de integrar un gen letal dominante bajo el control de un promotor específico en hembras inmaduras. El uso de esta técnica de modificación genética constituirá una herramienta importante para el manejo integrado de vectores(AU)

The ineffectiveness of current strategies for the chemical control of vector mosquitoes raises the need to develop novel approaches, among these are genetic strategies to reduce populations of vector mosquitoes or replace them with those that are not capable of transmitting pathogens, this is achieved through molecular tools that allow the manipulation and transgenesis of genes. Mosquito genome sequences and associated expressed sequence marker databases enable large-scale investigations to provide new insights into evolutionary, biochemical, genetic, metabolic, and physiological pathways. Furthermore, comparative genomics reveals the basis of evolutionary mechanisms with special attention to the specific interactions between vectors and pathogens. Transgenesis technology has been developed for the yellow fever and dengue mosquito, Aedes aegypti. Successful integration of exogenous DNA into the germ line of this mosquito with the transposable elements has been achieved. The availability of multiple elements and marker genes provides a powerful set of tools to investigate the basic biological properties of this insect vector, as well as the materials to develop new strategies for genetic control of mosquito populations based on the sterile insect technique. One of this strategy is to release radiation-sterilized males into the population; another, to integrate a dominant lethal gene under the control of a specific promoter in immature females. The use of this genetic modification technique will constitute an important tool for the integrated management of vectors(AU)