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Resumen Objetivos : Monitorear la actividad de oviposición del mosquito Aedes aegypti y de casos de dengue y chikun gunya en cuatro localidades de Argentina templada, durante la epidemia del 2023. Métodos : Durante el verano y otoño del 2023, se mo nitoreó semanalmente mediante ovitrampas la actividad de oviposición del mosquito vector, y se registró el arribo de casos con dengue o chikungunya a Tandil, Olavarría, Bahía Blanca y Laprida. Resultados : La variación mensual del porcentaje de trampas positivas fue similar en las tres primeras localidades; en Laprida no se detectó el mosquito. Por el contrario, se observó una diferencia significativa del porcentaje de trampas que alguna vez resultó positiva en cada localidad, siendo mayor en Olavarría (83%), que en Bahía Blanca (67%) y Tandil (49%). Respecto a las enfermedades, se registraron 18 casos importados de dengue y 3 de chikungunya. Además, se registró el primer caso autóctono de dengue en la región, siendo el más austral hasta el momento. Conclusión : Es imprescindible sensibilizar y capacitar a los integrantes de los sistemas de salud de las nue vas regiones expuestas al Ae. aegypti para la detección temprana de casos, y a la población en general para potenciar las acciones de prevención.
Abstract Objectives : To monitor the oviposition activity of the mosquito Aedes aegypti and of dengue and chikungunya cases in four localities of temperate Argentina, during the 2023 epidemic. Methods : During the summer and autumn of 2023, the oviposition activity of the mosquito vector was monitored weekly using ovitraps, and the arrival of cases with dengue or chikungunya in Tandil, Olavarría, Bahía Blanca and Laprida were registered. Results : Monthly variations of the percentage of positive traps were similar in the first three locations; in Laprida the mosquito was not detected. On the con trary, a significant difference was observed in the per centage of total traps that ever tested positive in each locality, being higher in Olavarría (83.3%) than in Bahía Blanca (68.6%) and Tandil (48.7%). Regarding diseases, 18 imported cases of dengue and 3 of chikungunya were registered. In addition, the first autochthonous case of dengue in the region was recorded, being the southern most until known. Conclusion : It is essential to raise awareness and train the members of the health systems of the new regions exposed to Ae. aegypti for early detection of cases, and to the general population to enhance pre vention actions.
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El Aedes aegypti transmite enfermedades graves como dengue, zika, chikungunya y fiebre amarilla, representando una amenaza para la salud pública. En Cochabamba, Bolivia, su proliferación es favorecida por el clima y la urbanización. Estudiar su colonización es crucial para desarrollar estrategias efectivas de control y prevención. Metodología: para revisar la colonización del Aedes aegypti en Cochabamba, se usaron bases de datos como Scielo, PubMed y Google Scholar. Se seleccionaron estudios relevantes con palabras clave como Aedes aegypti, Cochabamba y salud pública. Zotero se utilizó para organizar las referencias. Se llevó a cabo un análisis cualitativo y sistemático de los hallazgos. Desarrollo: el Aedes aegypti es un mosquito pequeño, identificado por sus marcas blancas en las patas y una marca en forma de lira en el tórax. Prefiere áreas urbanas con agua estancada para depositar sus huevos. Su ciclo de vida incluye etapas de huevo, larva, pupa y adulto, completándose en 8 a 10 días. La presencia del mosquito en Cochabamba ha sido documentada desde los años 80, con una expansión asociada a la densidad poblacional y la disponibilidad de hábitats adecuados. Estrategias de control incluyen campañas de educación pública, uso de insecticidas y vigilancia entomológica. Discusión: los estudios sobre la colonización del Aedes aegypti en Cochabamba muestran su adaptación a nuevas altitudes y áreas urbanas, influenciada por variaciones climáticas y urbanización desordenada. Factores como la escasez de agua y el almacenamiento inadecuado facilitan su proliferación. Se recomienda intensificar la educación pública y la participación comunitaria para eliminar criaderos.
Introduction: aedes aegypti transmits severe diseases such as dengue, Zika, chikungunya, and yellow fever, representing a significant public health threat. In Cochabamba, Bolivia, its proliferation is favored by the climate and urbanization. Studying its colonization is crucial for developing effective control and prevention strategies. Methodology: to review the colonization of Aedes aegypti in Cochabamba, databases such as Scielo, PubMed, and Google Scholar were used. Relevant studies were selected using keywords like Aedes aegypti, Cochabamba, and public health. Zotero was used to organize the references. A qualitative and systematic analysis of the findings was conducted. Development: Aedes aegypti is a small mosquito, identified by its white markings on the legs and a lyre-shaped marking on the thorax. It prefers urban areas with stagnant water to lay its eggs. Its life cycle includes the egg, larva, pupa, and adult stages, which it completes in 8 to 10 days. The presence of the mosquito in Cochabamba has been documented since the 1980s, with expansion associated with population density and the availability of suitable habitats. Control strategies include public education campaigns, insecticide use, and entomological surveillance. Discussion: studies on the colonization of Aedes aegypti in Cochabamba show its adaptation to new altitudes and urban areas, influenced by climate variations and unplanned urbanization. Factors such as water scarcity and inadequate storage facilitate its proliferation. It is recommended to intensify public education and community participation to eliminate breeding sites
Introdução: o Aedes aegypti transmite doenças graves como dengue, zika, chikungunya e febre-amarela, representando uma ameaça significativa à saúde pública. Em Cochabamba, Bolívia, sua proliferação é favorecida pelo clima e pela urbanização. Estudar sua colonização é crucial para desenvolver estratégias eficazes de controle e prevenção. Metodologia: para revisar a colonização do Aedes aegypti em Cochabamba, foram utilizadas bases de dados como Scielo, PubMed e Google Scholar. Estudos relevantes foram selecionados usando palavras-chave como Aedes aegypti, Cochabamba e saúde pública. O Zotero foi utilizado para organizar as referências. Foi realizada uma análise qualitativa e sistemática dos achados. Desenvolvimento: o Aedes aegypti é um mosquito pequeno, identificado por suas marcas brancas nas patas e uma marca em forma de lira no tórax. Prefere áreas urbanas com água estagnada para depositar seus ovos. Seu ciclo de vida inclui as fases de ovo, larva, pupa e adulto, completando-se em 8 a 10 dias. A presença do mosquito em Cochabamba é documentada desde a década de 1980, com uma expansão associada à densidade populacional e à disponibilidade de habitats adequados. As estratégias de controle incluem campanhas de educação pública, uso de inseticidas e vigilância entomológica. Discussão: os estudos sobre a colonização do Aedes aegypti em Cochabamba mostram sua adaptação a novas altitudes e áreas urbanas, influenciada por variações climáticas e urbanização desordenada. Fatores como a escassez de água e o armazenamento inadequado facilitam sua proliferação. Recomenda-se intensificar a educação pública e a participação comunitária para eliminar criadouros
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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.
Subject(s)
Environmental Monitoring , Aedes , Mosquito Control , Dengue , Insect VectorsABSTRACT
RESUMEN El dengue es una infección viral transmitida a través del mosquito Aedes aegypti y presenta cuatro serotipos (DENV-1 a DENV-4). La enfermedad desencadena una variedad de manifestaciones clínicas, desde formas leves sin signos de alarma hasta formas graves, potencialmente mortales. Se presenta el caso de un niño de cinco años, procedente de la provincia del Callao, cuyos síntomas iniciales fueron fiebre, cefalea y malestar general. Al tercer día, el niño manifiestó dolor abdominal leve y vómitos escasos; posteriormente, distensión abdominal, ictericia y coluria. Fue hospitalizado en la unidad de cuidados intensivos pediátricos con deshidratación moderada, ictericia, edemas, abdomen distendido y doloroso, matidez desplazable, hígado a 2 cm debajo del reborde costal derecho y lúcido. Por exámenes complementarios, se evidenció falla hepática, hepatoesplenomegalia y derrame pleural en bases. Se diagnosticó dengue grave a través de una prueba de ELISA Ig M reactivo más sobreinfección por probable peritonitis bacteriana espontánea. Se inició el tratamiento con antibióticos, furosemida, plasma fresco congelado, crioprecipitado y metamizol. Al no observarse mejoría, se optimizó el diurético y se administró albúmina humana. Mostró mejoría con disminución de ascitis, edemas, ictericia y efusión pleural; también mejora del perfil hepático y de la coagulación, además de encontrarse afebril. Presentó inesperadamente dificultad respiratoria por insuficiencia cardiaca congestiva debido a miocardiopatía dilatada según ecocardiografía; se manejó con diuréticos. Fue dado de alta en estado afebril, sin edemas y con resolución de falla hepática y trastorno de coagulación.
ABSTRACT Dengue is a viral infection which is transmitted by the Aedes aegypti mosquito and has four serotypes (DENV-1 to DENV-4). The disease triggers a variety of clinical manifestations, ranging from mild forms without warning signs to severe lifethreatening forms. We present the case of a 5-year-old boy, from the province of Callao, whose first symptoms were fever, headache and general malaise. On the third day, the child had mild abdominal pain and little vomiting; subsequently, abdominal distension, jaundice and choluria. He was admitted to the pediatric intensive care unit being alert and with moderate dehydration, jaundice, edema, distended and tender abdomen, shifting dullness and liver 2 cm below the right costal margin. Complementary tests revealed liver failure, hepatosplenomegaly and pleural effusion in the bases. Using a reactive IgM ELISA, severe dengue was diagnosed, as well as a superinfection due to probable spontaneous bacterial peritonitis. He started treatment with antibiotics, furosemide, fresh frozen plasma, cryoprecipitate and metamizole. As the child did not get better, the diuretic was optimized, and human albumin was administered. Thereafter, he got better showing decreased ascites, edema, jaundice and pleural effusion; improvement of the liver and coagulation profile; and being afebrile. He unexpectedly presented respiratory distress due to congestive heart failure caused by dilated cardiomyopathy diagnosed by echocardiography; thus, he was treated with diuretics. The patient was discharged afebrile, without edema and with resolution of liver failure and coagulation disorder.
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A incidência da dengue, doença viral transmitida pelo mosquito Aedes aegypti, vem crescendo em Porto Alegre ao longo dos anos, com recorde de casos registrados em 2022. Epidemias da doença parecem ocorrer de forma cíclica no município, com registros a cada três anos. Dada a influência de fatores climáticos no ciclo de vida do vetor, este trabalho buscou analisar a influência de determinantes meteorológicos na periodicidade de epidemias de dengue na capital gaúcha entre 2010 e 2022. Análises descritivas foram realizadas para averiguar o padrão dos indicadores climáticos e dos casos de dengue ao longo dos anos, ao passo que análises estatísticas foram feitas para avaliar a correlação entre os fatores climáticos e os casos autóctones registrados entre 2016 e 2022. Os resultados obtidos não apontaram padrões meteorológicos que se repetem a cada três anos e que poderiam explicar a ciclicidade observada. Ainda, não foram constatadas correlações entre temperatura, umidade e pluviosidade com casos autóctones de dengue no município, ao menos em nível quadrimestral. Para além destas análises, constatou-se expressivo aumento de casos em 2022, apesar dos esforços de controle desempenhados pelo poder público, o que aponta a necessidade de maior investimento em educação em saúde para a população. (AU)
The incidence of dengue, a viral disease transmitted by the Aedes aegypti mosquito, has been increasing in Porto Alegre over the years, with a record number of cases reported in 2022. Epidemics of the disease seem to occur cyclically in the city, with reports every three years. Given the influence of climatic factors on the vector's life cycle, this study aimed to analyze the influence of meteorological determinants on the periodicity of dengue epidemics in Porto Alegre between 2010 and 2022. Descriptive analyses were used to investigate the pattern of climatic indicators and dengue cases over the years, while statistical analyses were performed to evaluate the correlation between climatic factors and autochthonous cases registered between 2016 and 2022. The results did not point out meteorological patterns that repeat every three years and could explain the observed cyclicity. Furthermore, no correlations were found between temperature, humidity and rainfall and autochthonous dengue cases in the city, at least on a four-monthly basis. Beyond these analyses, a significant increase in dengue cases was observed in 2022, despite the efforts of the public authorities to control the disease, which highlights the need for greater investment in health education for the population. (AU)
Subject(s)
Climate , Aedes , Dengue , Meteorology , EpidemicsABSTRACT
La salud de la población selvática está en riesgo por la presencia del mosquito de la especie Aedes aegypti. Objetivo. Determinar el control de propagación y formas de prevención del dengue que afecta la salud de los pobladores de la región amazónica peruana. Materiales y métodos. Se realizó un estudio mixto, de carácter descriptivo fenomenológicos sobre la presencia del mosquito transmisor del dengue, la población estuvo constituida tres mil pobladores que viven alrededor de la laguna Yarinacocha en el distrito de Yarinacocha provincia de Coronel Portillo de la ciudad de Pucallpa, constando con una muestra representativa de veintidós familias a conveniencia del investigador y que pertenecen en calidad de estudiante de la Universidad Nacional Intercultural de la Amazonía. Se aplicó la observación y entrevista como técnica, además sus instrumentos como la ficha de observación y ficha de entrevista permitió identificar su conocimiento, tratamiento y prevención del dengue. Resultados. La mayoría de los pobladores conocen la forma de propagación, tratamiento y los cuidados de esta plaga que existe en la Amazonía, en consecuencia, el dengue es una enfermedad que afecta la salud de la población de la selva peruana, la detección y la intervención tardía en los pacientes complica la vida, por ello, optan a diversas alternativas para su tratamiento, prevención y para no propagación se utiliza conocimientos ancestrales y científicas. Conclusiones. El dengue es una enfermedad que se propaga rápidamente en las regiones donde hay presencia de zancudo, su complicación puede terminar en un derrame y fallecimiento en los pacientes de alto riesgo.
The health of the jungle population is at risk due to the presence of the Aedes aegypti mosquito. Objective. To determine the control of the spread and prevention of dengue that affects the health of the Peruvian Amazonian region. Materials and methods. The population consisted of three thousand inhabitants living around the Yarinacocha lagoon in the district of Yarinacocha in the province of Coronel Portillo in the city of Pucallpa, with a representative sample of twenty-two families at the convenience of the researcher and who belong as students of the National Intercultural University of the Amazon. Observation and interview were applied as a technique, in addition to their instruments such as the observation and interview forms, which allowed identifying their knowledge, treatment and prevention of dengue fever. Results. Most of the villagers know the way of propagation, treatment and care of this plague that exists in the Amazon, consequently, dengue is a disease that affects the health of the population of the Peruvian jungle, detection and late intervention in patients complicates their lives, therefore, they opt for various alternatives for treatment, prevention and for not spreading it using ancestral and scientific knowledge. Conclusions. Dengue is a disease that spreads rapidly in regions where the mosquito is present, its complication can end in a stroke and death in high-risk patients.
A saúde da população florestal está em risco devido à presença do mosquito Aedes aegypti. Objetivo. Determinar o controle da disseminação e a prevenção da dengue que afeta a saúde dos habitantes da região amazônica peruana. Materiais e métodos. Foi realizado um estudo misto, descritivo-fenomenológico, sobre a presença do mosquito transmissor da dengue, cuja população foi composta por três mil habitantes que vivem ao redor da lagoa Yarinacocha, no distrito de Yarinacocha, na província de Coronel Portillo, na cidade de Pucallpa, com uma amostra representativa de 22 famílias, de acordo com a conveniência do pesquisador e que são estudantes da Universidade Nacional Intercultural da Amazônia. A observação e as entrevistas foram usadas como técnicas, e instrumentos como os formulários de observação e entrevista foram usados para identificar seu conhecimento, tratamento e prevenção da dengue. Resultados. A maioria dos moradores conhece a forma de propagação, tratamento e cuidado desta praga que existe na Amazônia, consequentemente, a dengue é uma doença que afeta a saúde da população da selva peruana, a detecção e intervenção tardia nos pacientes complica a vida, portanto, optar por várias alternativas para o tratamento, prevenção e não propagação é usado conhecimento ancestral e científico. Conclusões. A dengue é uma doença que se espalha rapidamente em regiões onde os mosquitos estão presentes, e suas complicações podem levar a acidente vascular cerebral e morte em pacientes de alto risco.
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Resumo As arboviroses, sobretudo as transmitidas pelo mosquito Aedes aegypti, têm-se constituído em grave problema de saúde pública no Brasil. Com o intuito de analisar como o saneamento básico é abordado em instrumentos norteadores das políticas públicas de controle das arboviroses no país, foi realizada uma análise de conteúdo em oito documentos governamentais de referência. Como resultados, foi possível identificar que aspectos relacionados à comunicação e mobilização social, controle vetorial e gestão são os temas mais abordados nos documentos analisados. Já as componentes do saneamento básico, destacando-se o manejo e a drenagem das águas pluviais e o esgotamento sanitário não são abordados nos instrumentos. A intersetorialidade é mencionada, no entanto, não existem proposições específicas que apontem e assegurem sua implementação. As Diretrizes Nacionais para a Prevenção e Controle de Epidemias de Dengue, do Ministério da Saúde, constitui-se no documento mais completo sobre o assunto. Conclui-se que o saneamento básico não está suficientemente abordado nos instrumentos de enfrentamento às arboviroses o que pode contribuir para a baixa efetividade de intervenção pública e que, portanto, tal contradição precisa ser superada pelas políticas públicas no Brasil.
Abstract Arboviruses, especially those transmitted by the Aedes aegypti mosquito, have become a serious public health problem in Brazil. In order to analyze how sanitation is addressed in the basic guidelines of public policies to control arboviruses in the country, content analysis was performed on eight governmental reference documents. As a result, it was possible to identify that aspects related to communication and social mobilization, vector control, and management are the themes most addressed in the documents analyzed. On the other hand, the components of basic sanitation, especially rainwater management and drainage, and sewage control, are not addressed in the instruments. Intersectorality is mentioned, however, there are no specific proposals to implement the plan and ensure its implementation. The Ministry of Health's National Guidelines for the Prevention and Control of Dengue Epidemics is the most complete document on the subject. The conclusion drawn is that basic sanitation is not sufficiently addressed in the instruments for combatting arboviruses, which can contribute to the low effectiveness of public intervention and, consequently, this discrepancy needs to be focused on by public policies in Brazil.
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Introducción. El dengue es un problema de salud pública para el departamento de La Guajira. El control se ha enfocado en el vector con el uso de insecticidas, entre ellos los organofosforados. Objetivo. Evaluar el estado de la sensibilidad a insecticidas organofosforados de quince poblaciones de Aedes aegypti (L.) en el departamento de La Guajira, Colombia. Materiales y métodos. Se realizaron bioensayos para temefos, malatión y pirimifos- metil en larvas de tercer estadio y mosquitos adultos de Ae. aegypti en los municipios de Albania, Barrancas, Dibulla, Distracción, El Molino, Fonseca, Hatonuevo, La Jagua del Pilar, Maicao, Manaure, Riohacha, San Juan del Cesar, Uribia, Urumita y Villanueva, siguiendo la metodología de la Organización Mundial de la Salud (OMS) y la técnica de botellas usando la guía de los de los Centers for Disease Control and Prevention, respectivamente. Se determinó la sensibilidad por medio de la relación de resistencia a CL50 y CL95 (RRCL50, RRCL95) para temefos y a dosis y tiempo diagnóstico para temefos, malatión y pirimifos-metil en las poblaciones de campo evaluadas, usando como control la cepa sensible Rockefeller. Resultados. Las 15 poblaciones del departamento de La Guajira son sensibles a: temefos (relación de la resistencia a CL50<5,0; relación de resistencia a CL95<5,0; 98 a 100 % de mortalidad); pirimifos-metil (99 a 100 % de mortalidad) y malatión (100 % de mortalidad). Conclusión. Con base en los resultados obtenidos, es factible el uso de temefos, malatión y pirimifos-metil para el control de Ae. aegypti en las poblaciones evaluadas.
Introduction. Dengue is a public health problem in La Guajira region. Control has focused on the vector using insecticides, including organophosphates. Objective. To evaluate the state of susceptibility to organophosphates insecticides in fifteen Aedes aegypti (L.) populations in La Guajira, Colombia. Materials and methods. We collected samples of third-instar larvae and adult mosquitoes of Ae. aegypti in the municipalities of Albania, Barrancas, Dibulla, Distracción, El Molino, Fonseca, Hatonuevo, La Jagua del Pilar, Maicao, Manaure, Riohacha, San Juan del Cesar, Uribia, Urumita, Villanueva. Bioassays for temefos, malathion, and pirimiphos-methyl were carried out following the methodology of the World Health Organization, and the bottle technique using the guidance of the Centers for Disease Control and Prevention. Susceptibility to temefos was determined through the resistance ratio between lethal concentration 50 and lethal concentration 95; for the compounds temefos, malathion and pirimiphos-methyl, susceptibility was calculated using diagnostic dose and diagnostic time in the populations evaluated. Rockefeller susceptible strain was used as a control. Results. All evaluated populations of Ae. aegypti from La Guajira were found to be susceptible to temefos (ratio resistance to CL50<5.0; ratio resistance to CL95<5.0; 98 - 100 % mortality); pirimiphosmethyl (99 - 100 % mortality), and malathion (100 % mortality). Conclusion. Based on the results, the use of temefos, malathion, and pirimiphosmethyl is feasible for the control of Ae. aegypti in the evaluated populations.
Subject(s)
Aedes , Insecticides, Organophosphate , Temefos , Insecticide Resistance , Colombia , MalathionABSTRACT
Introducción: El dengue se ha convertido en un problema serio de salud pública en Bolivia. Por la capacidad de infección del virus del dengue, el diagnóstico es amplio y varia con la evolución de la enfermedad. El incremento de la temperatura y las lluvias de la época son los factores ambientales principales para la reproducción del mosquito transmisor (Aedes aegypti), y el aumento de casos de dengue. Objetivos: Realizar un estudio transversal-retrospectivo de los casos de dengue en el departamento de La Paz - Bolivia, durante el periodo de enero de 2020 hasta febrero de 2023. Materiales y Métodos: De las bases obtenidas del Laboratorio de Virología- INLASA, se analizaron variables como el número de casos positivos de cada gestión, la distribución de los casos positivos según el lugar probable de infección tanto por departamento como por provincia, la variación temporal de los casos y el serotipo prevalente por gestión, y la distribución de casos positivos por género y grupo etario, en este trabajo se realizó un estudio transversal-retrospectivo. Resultados: Durante las cuatro gestiones analizadas el número total de casos notificados fue de 2143, detectando 1184 (55.2%) positivos. Señalando como lugar probable de infección en gran parte la provincia de Sud Yungas. Con respecto a la variación temporal presentó un mismo comportamiento en tres gestiones. Prevaleció en tres gestiones el serotipo DENV 1 sobre DENV 2, observando un aumento de serotipo DENV 2 hasta febrero del 2023. Además, el grupo atareo más afectado con dengue oscila entre los 10 a 39 años, no encontrando diferencia significativa entre género masculino y femenino. Conclusiones: Este estudio revela que el dengue es un problema de salud pública no solo del oriente del país sino también de las zonas tropicales del departamento de La Paz. Es necesario el diagnóstico rápido y efectivo; realizar la tipificación del virus y el llenado correcto de fichas epidemiológicas para un mejor control virológico.
Background: Dengue has become a serious problem in public health in Bolivia. Due the infection capacity of dengue virus, the diagnosis is broad and varies with the evolution of the disease. The increase of temperature and rain season are the main environmental factors of reproduction in the transmitting mosquito (Aedes aegipty), and the increase in dengue cases. Objectives: To carry out a retrospective crossover study of dengue cases in La Paz Department - Bolivia, during the period from January 2020 to February 2023. Materials and Methods: From databases obtained from INLASA Virology Laboratory during periods 2020, 2021, 2022 and the beginnings of 2023, variables such as number of positive cases from each year, distribution of positive cases according to the probable place of infection were obtained and analyzed, by department and by province; the temporal variation of the cases and the prevalent serotype by period, and finally distribution of positive cases by sex group and age group. Its make a retrospective crossover study. Results: During the four analyzed periods, within the total number of 2143 reported cases, there were 1184 (55.2%) of positive cases for Dengue. On the other hand, the department of La Paz (86.3%) is indicated as the probable place of infection, with Sud Yungas province (municipalities La Asunta and Palos Blancos) being the places with the most positive cases. The temporal variation in suspected and confirmed cases has presented the same behavior in three years. DENV 1 serotype predominated over DENV 2 in three years, observing an increase in DENV 2 serotype until February 2023. In addition, the age group most affected by dengue ranges from 10 to 39 years, finding no significant difference between masculine and feminine gender. Discussions: An increase in cases between months of February and April, coinciding with rain season in Bolivia. Due to the climate in the tropical areas of the department, there is a greater number of positive cases in those areas. Conclusions: This study reveals that Dengue is a public health problem not only in eastern part of the country but also in tropical areas of La Paz department. A quick and effective diagnosis is necessary; to carry out the typing of the virus and the correct filling out of epidemiological files for better virological control.
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Aedes aegypti é o principal vetor dos agentes etiológicos de dengue, zika e chikungunya, doenças para as quais não existem vacinas totalmente eficazes. Alternativas de controle visando mitigar essas arboviroses são primordiais. Entre essas, o controle mecânico aborda práticas de eliminação e/ou limpeza de criadouros do vetor. Neste relato, apresentamos e avaliamos criticamente ações realizadas pelo grupo, ocorridas entre 2016 e 2019, nas quais divulgamos informação científica clara através do diálogo com a população. Os métodos utilizados foram: 1) palestras em escolas (público infantojuvenil) utilizando slides, fotos e vídeos; 2) oficinas (público misto), estande com material in vivo do ciclo de vida do Aedes, jogos e desenhos. Analisamos dez palestras em escolas do ensino fundamental e médio e vinte oficinas realizadas em diferentes regiões do Brasil. Concluímos que tais ações e suas análises críticas devem ser realizadas continuamente para que sejam bem-sucedidas
Aedes aegypti is the main vector of dengue, zika, and chikungunya etiological agents, diseases for which no effective vaccines are available. Control alternatives aimed at mitigating these arboviruses are essential. Among such, mechanical control addresses practices of elimination and/or cleaning of vector breeding sites. Here, we presented and critically evaluated actions carried out by ourselves. These actions took place between 2016 and 2019, where we disseminated clear scientific information through dialogue with the population. The following methods were employed: 1) lectures in schools (children and youth audiences) using slides, photos, and videos; 2) workshops (mixed audience), stand with in vivo material from the Aedeslife cycle, games, and drawings. Ten lectures in elementary and high schools and twenty workshops held in different regions of Brazil were analyzed. It was concluded that such actions and their critical analyzes must be carried out continuously to be successful
Aedes aegypti es el principal vector de los agentes etiológicos del dengue, zika y chikungunya, enfermedades para las que no existen vacunas totalmente eficaces. Las alternativas de control para mitigar estas arbovirosis son fundamentales. El control mecánico, representa una de estas alternativas, aborda prácticas de eliminación y/o limpieza de criaderos del vector. En este informe presentamos y evaluamos de manera crítica las acciones realizadas por el grupo entre los años 2016 y 2019. Presentamos información científica clara a través del diálogo con la población mediante los siguientes métodos: 1) conferencias en escuelas (público infantil) utilizando diapositivas, fotos y videos; 2) Talleres (público mixto), stand con material in vivo del ciclo de vida del Aedes, juegos y dibujos. Analizamos diez conferencias en escuelas (primarias y secundarias) y veinte talleres realizados en diferentes regiones de Brasil. Concluimos que tales acciones y el análisis crítico de las mismas deben llevarse a cabo de manera continua para que resulten exitosas.
Subject(s)
Humans , Child , Adolescent , Mosquito Control , Health Education/methods , Aedes/growth & development , Educational and Promotional Materials , Teaching Materials , Brazil , Health Fairs , Dengue/prevention & control , Qualitative Research , Chikungunya Fever/prevention & control , Zika Virus Infection/prevention & control , Health Promotion/methodsABSTRACT
Aedes aegypti (Linnaeus) plays an important role as a vector of different deadly diseases particularly dengue fever. Insecticides are used as a primary tool to control Ae. aegypti. However, due to the excessive use of insecticides on agricultural, public health, and industrial levels, mosquitoes have developed resistance. In this study, the current susceptibility status of Ae. aegypti mosquitoes against different insecticides (Temephos, DDT, dieldrin, Malathion, Bendiocarb, Permethrin, Cypermethrin, and Lambda-cyhalothrin) was evaluated in district Lahore and district Muzaffargarh of Punjab, Pakistan. For this purpose, WHO bioassays and biochemical assays were performed on Ae. aegypti population from Lahore (APLa) and Aedes population from Muzaffargarh (APMg). Results of APLa and APMg showed high levels of resistance against the larvicide Temephos. Resistance against all adulticides was also observed in APLa and APMg (% mortality < 98%). The biochemical assays indicated statistically significant elevated levels of detoxification enzymes in APLa and APMg. APLa showed slightly higher levels as compared to APMg. Mosquitoes were also screened for the presence of kdr mutations. The results revealed no mutation in domain II while the presence of mutation F1534C in domain III was found in both field populations. The results showed the presence of moderate to high grade resistance against all insecticides in Ae. aegypti in district Lahore and district Muzaffargarh of Punjab, Pakistan
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Background & objectives: Nanotechnology, an emerging field, has acquired considerable attention for the control of vectors. The present study aimed to synthesize, characterize copper sulfide- and eucalyptus oil-based hybrid nanoemulsions and investigate their larvicidal potential against Aedes aegypti by studying larvicidal bioassay, morphological aberrations, histopathological alterations, biochemical analysis and evaluation of risk assessment in non-target organisms. Methods: Hybrid nanoemulsions were prepared by mixing aqueous copper sulfide nanoparticles (CuSNPs) with non-polar eucalyptus oil in five ratios (1:1, 1:2, 1:3, 1:4 and 1:5) by sonication, screened and characterized using Transmission electron microscopy (TEM). Larvicidal activity was recorded and toxicity values were calculated by log-probit method. Morphological, histological and biochemical changes were examined in Aedes aegypti larvae after treatment. Nanohybrids were also tested under simulated conditions and against non-target organism. Results: The nanohybrid ratio of 1:5 was found to be stable after thermodynamic stability tests. TEM studies revealed average size of 90±7.90 nm with globular shape. LC50 and LC90 toxicity values of prepared CuSNPs were calculated out to be 5.00 and 5.81ppm after 24 hours treatment. Effective concentration of prepared nanohybrid (6.5ppm) tested under simulated conditions showed maximum larvicidal mortality after 48 hours of exposure. No toxicity towards the Mesocyclops spp. was observed after treatment of these nanohybrids even up to 21 days. Interpretation & conclusion: Copper sulfide based hybrid nanoemulsions were found to show efficient larvicidal property which can be used for the formulation of ecofriendly bio-larvicide against Aedes aegypti.
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@#Abstract: Objective To construct a shuttle vector pHT315-AaCPR100A with two spore-producing-dependent promoters and the target gene AaCPR100A in Escherichia coli-Bacillus thuringiensis. Methods The forward promoter of Cry3A, named Pro-1 (+), was amplified by PCR using pSVP27A plasmid as the template, and the target gene AaCPR100A was amplified using Aedes aegypti RNA reverse conversion cDNA as the template. The plasmid pHT315 was linearized by digestion with Hind Ⅲ and Sal Ⅰ. The forward promoter and the target gene were inserted into the linearized vector pHT315 successively by in-fusion cloning according to the transcription direction. The synthesized plasmid containing the Cry3A reverse promoter sequence was used as the template, and the Pro-1 (-) reverse promoter was amplified by PCR. The intermediate vector containing the forward promoter and the target gene was linearized by EcoR I restriction enzyme, and the reverse promoter was inserted downstream of the target gene by in-fusion cloning in the direction of transcription. Results By agarose gel electrophoresis, the forward promoter, target gene AaCPR100A and reverse promoter bands were clear and of good quality, which could be used for in-fusion cloning experiments. The two spore-producing-dependent promoters and target gene fragments were connected by In-fusion cloning. The recombinant vector pHT315-AaCPR100A was verified by PCR. The forward promoter, target gene fragment and reverse promoter were successfully amplified in the recombinant vector. Nucleotide sequencing verified that the sequencing results of the bidirectional promoter sequence and the target gene sequence were basically consistent with the sequence alignment results, which met the requirements of the construction of vector elements and proved that the recombinant vector was successfully constructed. Conclusions Based on the above results, this study proves that the recombinant shuttle vector with two spore-producing-dependent promoters can be successfully constructed by in-fusion cloning technology, laying the foundation for the construction of engineered Bacillus thuringiensis expressing dsRNA of AaCPR100A.
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@#Abstract: Objective In order to explore the application prospects of the phenyl pyrazole insecticide fipronil for mosquito control and identify potential target genes involved in the resistance of Aedes aegypti to fipronil, and lay the foundation for an in-depth study of the resistance mechanism of Aedes aegypti to fipronil. Methods Using Aedes aegypti sensitive strains as experimental materials, Aedes aegypti larvae were treated with fipronil, and the differences in gene expression of Aedes aegypti larvae before and after drug administration were compared at the transcriptome level using transcriptome sequencing combined with bioinformatics analysis, and the differential genes were analyzed. Results A total of 757 differentially expressed genes were identified between the fipronil-treated group and control group, including 217 and 540 up- and down-regulated genes, respectively. Among these, the expression of glutamate-gated chloride channel (GluCls) genes varied significantly before and after treatment. Gene ontology analysis revealed that differentially expressed genes were enriched in catalytic activity, binding, metabolic processes, and membrane-related functions, while KEGG pathway analysis indicated enrichment in biosynthesis, metabolism, and life regulation processes, while the glutathione metabolic pathway was enriched in 15 differentially expressed genes. Conclusions The transcriptome results revealed that GST gene expression was significantly upregulated in fipronil-treated Aedes aegypti larvae, indicating that GST gene is involved in the development of fipronil resistance in Aedes aegypti larvae. In addition, GluCls gene expression was also significantly different before and after treatment, suggesting that GluCls migh be a potential target receptor for fipronil resistance in Aedes aegypti. As GluCls is an ideal target receptor found only in invertebrates, this discovery provides a reference and basis for further exploration of the toxicological mechanism of fipronil on Aedes aegypti.
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Abstract The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 μg mL-1 were obtained for the essential oil and 4.36 μg mL-1 for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 μg mL-1 for the essential oil of citronella and 86.30 μg mL-1 for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.
Resumo O óleo essencial de citronela (Cymbopogon winterianus) possui diversas atividades biológicas, entre elas a ação repelente a insetos. Alguns estudos mostraram que os ésteres do ácido cinâmico podem ser aplicados como pesticidas naturais, inseticidas e fungicidas. Nesse contexto, o objetivo do presente trabalho foi avaliar a produção de ésteres a partir do óleo essencial de citronela com ácido cinâmico via esterificação enzimática. Além disso, foi investigada a toxicidade do óleo essencial antes e após a esterificação contra Artemia salina e a ação larvicida sobre Aedes aegypti. Os ésteres foram produzidos utilizando ácido cinâmico como agente acilante e óleo essencial de citronela (3: 1) em heptano e 15% em peso da enzima NS 88011 como biocatalisadores, a 70 ° C e 150 rpm. As taxas de conversão de cinamatos de citronelil e geranil foram 58,7 e 69,0% para NS 88011, respectivamente. Para a toxicidade sobre Artemia salina foram obtidos CL50 de 5,29 μg mL-1 para o óleo essencial e 4,36 μg mL-1 para os óleos esterificados com NS 88011. Na atividade inseticida contra larvas de Aedes aegypti, obteve-se CL50 de 111,84 μg mL-1 para o óleo essencial de citronela e 86,30 μg mL-1 para os óleos esterificados com a enzima NS 88011, indicando alta toxicidade dos ésteres. Os resultados demonstraram que as amostras avaliadas apresentam potencial de aplicação como bioinseticida.
Subject(s)
Animals , Oils, Volatile/toxicity , Aedes , Cymbopogon , Insect Repellents , Insecticides/toxicity , Esterification , LarvaABSTRACT
Abstract Numerous studies have investigated the chemical composition and biological activities of essential oils from different Citrus species fruit peel, leaves and flowers. This paper aims to investigate the chemical composition, larvicidal and antileishmanial activities of essential oil from Citrus reticulata fruit peel (CR-EO). CR-EO was obtained by hydrodistillation in a Clevenger-type apparatus and its chemical composition was analyzed by GC-MS and GC-FID. Limonene (85.7%), ɣ-terpinene (6.7%) and myrcene (2.1%) were identified as its major components. CR-EO showed high activity against promastigote forms of Leishmania amazonensis (IC50 = 8.23 µg/mL). CR-EO also exhibited high larvicidal activity against third instar Aedes aegypti larvae at a lethal concentration (LC50 = 58.35 µg/mL) and 100% mortality at 150 µg/mL. This study suggests, for the first time, the potential use of CR-EO against this important mosquito-borne viral disease caused by the genus Aedes.
Resumo Numerosos estudos têm investigado a composição química e as atividades biológicas de óleos essenciais extraídos de cascas dos frutos, folhas e flores de diferentes espécies de Citrus. Este trabalho tem como objetivo investigar a composição química e as atividades larvicida e leishmanicida in vitro do óleo essencial das cascas dos frutos de Citrus reticulata (CR-EO). CR-EO foi obtido pela técnica de extração em aparelho Clevenger e sua composição química foi determinada por CG-EM e CG-DIC. Limoneno (85,7%), ɣ-terpineno (6,7%) and mirceno (2,1%) foram identificados como os constituintes majoritários. CR-EO mostrou alta atividade contra as formas promastigota de Leishmania amazonensis (CI50 = 8,23 µg/mL). CR-EO também exibiu alta atividade larvicida contra as larvas do terceiro estágio do Aedes aegypti com concentração letal (CL50 = 58,35 µg/mL) e mortalidade de 100% em 150 µg/mL. Este estudo sugere, pela primeira vez, o uso potencial de CR-EO contra esta importante doença viral transmitida por mosquitos do gênero Aedes.
Subject(s)
Animals , Oils, Volatile/pharmacology , Citrus , Aedes , Insecticides/pharmacology , Fruit , LarvaABSTRACT
Resumen OBJETIVO: Describir las características sociodemográficas y clínicas y determinar los factores asociados con la hospitalización y la oportunidad de consulta en embarazadas notificadas con dengue en Cali, Colombia. MATERIALES Y MÉTODOS: Estudio observacional, analítico y retrospectivo de base poblacional. Descripción de las características sociodemográficas y clínicas de las embarazadas con dengue que se notificaron al Sistema de Vigilancia en Salud Pública (SIVIGILA). Para identificar los factores asociados con la hospitalización se aplicó un modelo de regresión logística y para el procesamiento estadístico se utilizó SPSS versión 26. RESULTADOS: Se estudiaron 674 embarazadas con dengue, 63.9% (n = 431) sin signos de alarma, 36.1% (n = 243) con signos de alarma y ningún caso de dengue grave. En cuanto a la conducta, el 42.3% ( n = 285) se trató de manera ambulatoria, 39.5% (n = 266) en el hospital;12.5% (n = 84) permaneció en observación, 1.9% (n = 13) requirió el envío a otro centro de salud para su hospitalización y el 3.9% (n = 26) requirió atención en cuidados intensivos. CONCLUSIONES: En las embarazadas, la infección por dengue aumenta la morbilidad; los principales factores asociados con la hospitalización fueron: trombocitopenia, hipotensión, dolor abdominal, erupción cutánea y vómito. Por parte de las entidades de salud y la comunidad se requieren intervenciones efectivas enfocadas a la manipulación de residuos y educación e insistencia en los principales signos de alarma por los que deben solicitar la consulta médica.
Abstract OBJECTIVE: To describe the sociodemographic and clinical characteristics and to determine the factors associated with hospitalization and timeliness of consultation in pregnant women notified with dengue fever in Cali, Colombia. MATERIALS AND METHODS: Observational, analytical and retrospective population-based study. Description of the sociodemographic and clinical characteristics of pregnant women with dengue reported to the Public Health Surveillance System (SIVIGILA). A logistic regression model was applied to identify factors associated with hospitalization and SPSS version 26 was used for statistical processing. RESULTS: A total of 674 pregnant women with dengue were studied, 63.9% (n = 431) without alarm signs, 36.1% (n = 243) with alarm signs and no cases of severe dengue. In terms of behavior, 42.3% ( n = 285) were treated on an outpatient basis, 39.5% (n = 266) in hospital;12.5% (n = 84) remained under observation, 1.9% (n = 13) required referral to another health center for hospitalization and 3.9% (n = 26) required intensive care. CONCLUSIONS: In pregnant women, dengue infection increases morbidity; the main factors associated with hospitalization were: thrombocytopenia, hypotension, abdominal pain, rash, and vomiting. On the part of the health entities and the community, effective interventions focused on waste handling and education and insistence on the main warning signs for which they should seek medical consultation are required.
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A dengue é uma das doenças virais mais distribuídas pelo mundo. Por meio de uma revisão integrativa, este estudo busca identificar os possíveis fatores socioambi- entais associados à prevalência dos casos de dengue. Foi realizada uma pesquisa em es- tudos indexados nas bases de dados: Biblioteca Virtual em Saúde (BVS) e Literatura La- tino-Americana e do Caribe em Ciências da Saúde (LILACS), no período de 2017 a 2023, utilizando-se os seguintes descritores (DeCS): dengue, aedes aegypti e infecções por ar- bovírus. Em seguida, foram selecionados quinze trabalhos, que foram publicados em por- tuguês e espanhol. Os resultados mostraram que a dengue está relacionada a diversos fatores, ligados a esfera social e ambiental. Inicialmente, observou-se que o crescimento urbano desordenado desencadeou uma série de questões que contribuem para o aumento dos casos de dengue e o consequente impacto sobre a saúde pública. Entre os principais fatores sociais, verificou-se um crescimento populacional nas cidades, o que levou ao agravamento da desigualdade social, elevação das moradias precárias e necessidade de melhor infraestrutura. Entre os principais fatores ambientais, pode-se destacar a deficiên- cia no fornecimento de água, o que costuma levar as pessoas a buscarem armazenar água em reservatórios descobertos. Além disso, é comum a ocorrência do manejo inadequado dos resíduos sólidos. Portanto, o trabalho evidenciou os fatores que estão associados à prevalência da dengue, assim como mostrou a necessidade de investimento em diversas áreas, no intuito de diminuir a desigualdade social.
Dengue is one of the most widespread viral diseases in the world. Through an integrative review, this study seeks to identify possible socio-environmental factors associated with the prevalence of dengue cases. A search was carried out on studies in- dexed in the databases: Virtual Health Library (BVS) and Latin American and Caribbean Literature on Health Sciences (LILACS), from 2017 to 2023, using the following de- scriptors (DeCS): dengue, aedes aegypti and arbovirus infections. Then, fifteen works were selected, which were published in Portuguese and Spanish. The results showed that dengue is related to several factors, linked to the social and environmental sphere. Ini- tially, it was observed that disorderly urban growth has triggered a series of issues that contribute to the increase in dengue cases and the consequent impact on public health. Among the main social factors, there was a population growth in the cities, which led to the worsening of social inequality, an increase in precarious housing and the need for better infrastructure. Among the main environmental factors, we can highlight the defi- ciency in the water supply, which usually leads people to seek to store water in uncovered reservoirs. In addition, the occurrence of inadequate management of solid waste is com- mon. Therefore, the work highlighted the factors that are associated with the prevalence of dengue, as well as showing the need for investment in several areas, in order to reduce social inequality.
El dengue es una de las enfermedades virales más extendidas en el mundo. A través de una revisión integradora, este estudio busca identificar posibles factores so- cioambientales asociados a la prevalencia de casos de dengue. Se realizó una búsqueda en estudios indexados en las bases de datos: Biblioteca Virtual en Salud (BVS) y Litera- tura Latinoamericana y del Caribe en Ciencias de la Salud (LILACS), de 2017 a 2023, utilizando los siguientes descriptores (DeCS): dengue, aedes aegypti y arbovirus infec- ciones Luego, quince obras fueron seleccionadas, que fueron publicadas en portugués y español. Los resultados mostraron que el dengue está relacionado con varios factores, vinculados a las esferas social y ambiental. Inicialmente, se observó que el crecimiento urbano desordenado desencadenó una serie de problemas que contribuyen al aumento de casos de dengue y el consecuente impacto en la salud pública. Entre los principales fac- tores sociales, hubo un crecimiento de la población en las ciudades, lo que condujo al recrudecimiento de la desigualdad social, aumento de la vivienda precaria y la necesidad de mejorar la infraestructura. Entre los principales factores ambientales, se puede destacar la deficiencia en el suministro de agua, lo que suele llevar a las personas a buscar alma- cenar agua en reservorios descubiertos. Además, es común la ocurrencia de un inade- cuado manejo de los residuos sólidos. Por lo tanto, el trabajo destacó los factores que están asociados a la prevalencia del dengue, además de mostrar la necesidad de inversión en varias áreas, con el fin de reducir la desigualdad social.
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BACKGROUND The massive use of insecticides in public health has exerted selective pressure resulting in the development of resistance in Aedes aegypti to different insecticides in Venezuela. Between 2010 and 2020, the only insecticides available for vector control were the organophosphates (Ops) fenitrothion and temephos which were focally applied. OBJECTIVES To determine the state of insecticide resistance and to identify the possible biochemical and molecular mechanisms involved in three populations of Ae. aegypti from Venezuela. METHODS CDC bottle bioassays were conducted on Ae. aegypti collected between October 2019 and February 2020 in two hyperendemic localities for dengue in Aragua State and in a malaria endemic area in Bolívar State. Insecticide resistance mechanisms were studied using biochemical assays and polymerase chain reaction (PCR) to detect kdr mutations. FINDINGS Bioassays showed contrasting results among populations; Las Brisas was resistant to malathion, permethrin and deltamethrin, Urbanización 19 de Abril was resistant to permethrin and Nacupay to malathion. All populations showed significantly higher activity of mixed function oxidases and glutathione-S-transferases (GSTs) in comparison with the susceptible strain. The kdr mutations V410L, F1534C, and V1016I were detected in all populations, with F1534C at higher frequencies. MAIN CONCLUSION Insecticide resistance persists in three Ae. aegypti populations from Venezuela even in the relative absence of insecticide application.
ABSTRACT
The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 μg mL-¹ were obtained for the essential oil and 4.36 μg mL-¹ for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 μg mL-¹ for the essential oil of citronella and 86.30 μg mL-¹ for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.
O óleo essencial de citronela (Cymbopogon winterianus) possui diversas atividades biológicas, entre elas a ação repelente a insetos. Alguns estudos mostraram que os ésteres do ácido cinâmico podem ser aplicados como pesticidas naturais, inseticidas e fungicidas. Nesse contexto, o objetivo do presente trabalho foi avaliar a produção de ésteres a partir do óleo essencial de citronela com ácido cinâmico via esterificação enzimática. Além disso, foi investigada a toxicidade do óleo essencial antes e após a esterificação contra Artemia salina e a ação larvicida sobre Aedes aegypti. Os ésteres foram produzidos utilizando ácido cinâmico como agente acilante e óleo essencial de citronela (3: 1) em heptano e 15% em peso da enzima NS 88011 como biocatalisadores, a 70 ° C e 150 rpm. As taxas de conversão de cinamatos de citronelil e geranil foram 58,7 e 69,0% para NS 88011, respectivamente. Para a toxicidade sobre Artemia salina foram obtidos CL50 de 5,29 μg mL-¹ para o óleo essencial e 4,36 μg mL-¹ para os óleos esterificados com NS 88011. Na atividade inseticida contra larvas de Aedes aegypti, obteve-se CL50 de 111,84 μg mL-¹ para o óleo essencial de citronela e 86,30 μg mL-¹ para os óleos esterificados com a enzima NS 88011, indicando alta toxicidade dos ésteres. Os resultados demonstraram que as amostras avaliadas apresentam potencial de aplicação como bioinseticida.