RESUMO
Dengue fever, caused by the dengue virus (DENV), poses a significant global health challenge, particularly in tropical and subtropical regions. Recent increases in indigenous DENV cases in Europe are concerning, reflecting rising incidence linked to climate change and the spread of Aedes albopictus mosquitoes. These vectors thrive under environmental conditions like temperature and humidity, which are increasingly influenced by climate change. Additionally, global travel accelerates the cross-border spread of mosquito-borne diseases. DENV manifests clinically in a spectrum from asymptomatic cases to severe conditions like dengue hemorrhagic fever and dengue shock syndrome, influenced by viral serotype and host factors. In 2024, Brazil experienced a fourfold increase in dengue cases compared to 2023, accompanied by higher mortality. Conventional control measures, such as vector control, community engagement, and vaccination, proved insufficient as climate change exacerbated mosquito proliferation, challenging containment efforts. In this regard, our review analyzes prevention measures and therapeutic protocols during the outbreak while addressing DENV transmission dynamics, clinical presentations, and epidemiological shifts. It also evaluates diagnostic strategies combining clinical assessment with serological and molecular testing, providing information to improve diagnostic and preventive measures. The global expansion of dengue-endemic regions, including outbreaks in Europe, highlights the urgent need for enhanced surveillance, proactive interventions, and international collaboration to mitigate the growing threat of Dengue and other arboviruses like West Nile, Zika, Chikungunya, Oropouche, and Yellow Fever viruses.
Assuntos
Aedes , Vírus da Dengue , Dengue , Surtos de Doenças , Saúde Global , Mosquitos Vetores , Humanos , Dengue/epidemiologia , Dengue/transmissão , Animais , Aedes/virologia , Mosquitos Vetores/virologia , América Latina/epidemiologia , Mudança ClimáticaRESUMO
Mosquito-transmitted viruses such as dengue are a global and growing public health challenge. Without widely available vaccines, mosquito control is the primary tool for fighting the spread of these viruses. New mosquito control technologies are needed to complement existing methods, given current challenges with scalability, acceptability, and effectiveness. A field trial was conducted in collaboration with the Communities Organized to Prevent Arboviruses project in Ponce, Puerto Rico, to measure entomological and epidemiological effects of reducing Aedes aegypti populations using Wolbachia incompatible insect technique. We packed and shipped Wolbachia-males from California and released them into 19 treatment clusters from September 2020 to December 2020. Preliminary evaluation revealed sub-optimal Wolbachia-male densities and impact on the wild-type population. In 2021, we shifted to a phased release strategy starting in four clusters, reducing the mosquito population by 49% (CI 29-63%). We describe the investigation into male quality and other factors that may have limited the impact of Wolbachia-male releases. Laboratory assays showed a small but significant impact of packing and shipping on male fitness. However, mark-release-recapture assessments suggest that male daily survival rates in the field may have been significantly impacted. We compared induced-sterility levels and suppression of the wild population and found patterns consistent with mosquito population compensation in response to our intervention. Analysis of epidemiological impact was not possible due to very low viral transmission rates during the intervention period. Our entomological impact data provide evidence that Wolbachia incompatible-male releases reduced Ae. aegypti populations, although efficacy will be maximized when releases are part of an integrated control program. With improvement of shipping vessels and shipped male fitness, packing and shipping male mosquitoes could provide a key solution for expanding access to this technology. Our project underscores the challenges involved in large and complex field effectiveness assessments of novel vector control methods.
Assuntos
Aedes , Controle de Mosquitos , Mosquitos Vetores , Wolbachia , Animais , Aedes/microbiologia , Aedes/virologia , Aedes/fisiologia , Masculino , Porto Rico/epidemiologia , Wolbachia/fisiologia , Controle de Mosquitos/métodos , Mosquitos Vetores/virologia , Mosquitos Vetores/microbiologia , Feminino , Controle Biológico de Vetores/métodos , Dengue/prevenção & controle , Dengue/transmissão , Dengue/epidemiologiaRESUMO
BACKGROUND: Aedes aegypti is the primary vector of dengue, chikungunya, and Zika viruses in Colombia. Various insecticides, including pyrethroid, organophosphate, and carbamate insecticides; growth regulators; and biological insecticides, such as Bacillus thuringiensis var. israelensis, have been used to control Ae. aegypti populations. However, organophosphates such as malathion, pirimiphos-methyl, and temephos have been used over the last decade owing to the high resistance to pyrethroids. METHODS: This study assessed the susceptibility to organophosphates in 14 Ae. aegypti populations from the Córdoba department in northern Colombia. Moreover, possible resistance mechanisms were investigated by determining the activity levels of α-esterases, ß-esterases, mixed function oxidases (MFOs), glutathione S-transferases (GSTs), and insensitive acetylcholinesterase (iAChE). Additionally, the Ace-1 gene was sequenced to identify mutations at the target site of action. RESULTS: The populations were susceptible to temephos and malathion but resistant to fenitrothion, and in three of them, to pirimiphos-methyl. Alterations in the enzyme activity levels of α-esterases and ß-esterases, GST, and iAChE were observed among the populations, with high enzyme activity levels of α and ß esterases associated with resistance to fenitrothion. No mutations were identified in the Ace-1 gene. CONCLUSIONS: These findings are highly relevant for vector control programs in the region, as they allow for adjustments in resistance management strategies and improve the effectiveness of interventions against these arboviruses.
Assuntos
Aedes , Resistência a Inseticidas , Inseticidas , Mosquitos Vetores , Organofosfatos , Animais , Aedes/efeitos dos fármacos , Aedes/genética , Colômbia , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Mosquitos Vetores/efeitos dos fármacos , Mosquitos Vetores/genética , Organofosfatos/farmacologia , Acetilcolinesterase/metabolismo , Acetilcolinesterase/genética , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Temefós/farmacologia , Esterases/metabolismo , Esterases/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismoRESUMO
Dengue remains a significant public health concern in Brazil, with all federative units registering occurrences of the disease within their territories despite constant measures to control the Aedes aegypti vector. This study aimed to evaluate the profile of notified dengue cases in the Brazilian Legal Amazon from 2001 to 2021, analyzing National System of Notifiable Diseases (SINAN) data on the disease to assess the risks for its occurrence. Subsequently, statistical analyses were conducted to identify incidence and lethality rates. Over the study period, approximately 1,344,950 cases of the disease were reported, resulting in 863 deaths. The transmission of cases in the Amazonian states was not homogeneous, demonstrating variations and clusters over the years of extreme value for health authorities. Identifying and understanding the spatiotemporal patterns for the disease in the region helps assess the behavior of infections in areas with high susceptibility, promoting targeted interventions and resource allocation for dengue control programs. It is important to encourage future studies that evaluate the disease's risk based on quantitative variables. Such studies contribute to the formulation of health policies aimed at controlling and preventing dengue, improving public health outcomes.
Assuntos
Dengue , Análise Espaço-Temporal , Dengue/epidemiologia , Dengue/transmissão , Brasil/epidemiologia , Humanos , Incidência , Feminino , Aedes/virologia , Masculino , Animais , Criança , Adolescente , Adulto , Pré-Escolar , Pessoa de Meia-Idade , Adulto Jovem , Mosquitos Vetores/virologia , Lactente , IdosoRESUMO
Mosquitoes are the primary vectors of arthropod-borne pathogens. Aedes aegypti is one of the most widespread mosquito species worldwide, responsible for transmitting diseases such as Dengue, Zika, and Chikungunya, among other medically significant viruses. Characterizing the array of viruses circulating in mosquitoes, particularly in Aedes aegypti, is a crucial tool for detecting and developing novel strategies to prevent arbovirus outbreaks. In this study, we address the implementation of a sequencing and analysis pipeline based on the Oxford Nanopore Technologies MinION Mk1b system, for arboviral detection in field-caught mosquitoes from Argentina. Full genome of Humaita Tubiacanga Virus (HTV), Phasi Charoen-like Phasivirus (PCLV), Aedes aegypti totivirus (AaeTV) has been sequenced in three distinct regions of Argentina comprising Buenos Aires province, Santa Fe province and the northern province of Salta. Viral sequences enriched by SISPA and coupled with Nanopore sequencing can be a useful tool for viral surveillance, not only for detecting viruses that have a high impact on human and animal health, but also for detecting insect-specific viruses that could promote the transmission of arboviruses.
Assuntos
Aedes , Mosquitos Vetores , Vírus de RNA , Animais , Aedes/virologia , Argentina , Vírus de RNA/genética , Vírus de RNA/isolamento & purificação , Vírus de RNA/classificação , Mosquitos Vetores/virologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Genoma Viral , Arbovírus/isolamento & purificação , Arbovírus/genética , Arbovírus/classificação , Vírus de Insetos/genética , Vírus de Insetos/isolamento & purificação , Vírus de Insetos/classificaçãoRESUMO
The virulence of encapsulated fungal conidia against Aedes aegypti larvae was investigated. Molecular studies confirmed that the fungal isolate used here was Beauveria bassiana. Different conidial concentrations were tested. A concentration of 1 × 108 conidia mL- 1 was the most effective, resulting in 7% larval survival after 7 days. Next, alginate capsules (0.65%) containing conidia were prepared with different densities of calcium chloride (0.01 M, 0.009 M, and 0.008 M CaCl2) and tested against larvae. Furthermore, groups of capsules were prepared with bird diet to act as an attractant. All capsule densities tested reduced larval survival (ranging from 22 to 67%). However, capsules with 0.008 M CaCl2 were the most effective. Furthermore, fungus-only capsules were more efficient when compared to those containing bird diet. Laboratory and semi-field bioassays were conducted using mixtures of capsules with different densities. In the laboratory, survival ranged from 26 to 53%, whereas in semi-field conditions, 35%, and 80% survival was observed for groups exposed to fungus-only capsules or capsules containing diet, respectively. Histopathological studies of larvae exposed to capsules showed the presence of the fungus in the digestive tract and visible damage to enterocytes. These findings offer new insights into the biological control of Ae. aegypti larvae.
Assuntos
Aedes , Beauveria , Larva , Controle Biológico de Vetores , Esporos Fúngicos , Animais , Aedes/microbiologia , Larva/microbiologia , Beauveria/patogenicidade , Beauveria/fisiologia , Controle Biológico de Vetores/métodos , Controle de Mosquitos/métodosRESUMO
There is a pressing need for innovative strategies to control arboviruses transmitted by Aedes aegypti. The modification of indoor residual spraying to target Ae. aegypti is one such strategy. A clinical trial quantifying the epidemiologic impact of targeted indoor residual spraying for Ae. aegypti control used a product with pirimiphos-methyl as the active ingredient in the city of Mérida, Mexico. To monitor the susceptibility of local Ae. aegypti populations over the course of the trial, we calculated a diagnostic dose for pirimiphos-methyl using the Centers for Disease Control and Prevention bottle assay. Two independent laboratories tested a series of 8 concentrations of pirimiphos-methyl, eliciting a range of mortality between 0% and 100% in an insecticide-susceptible reference strain of Ae. aegypti. The results suggested a diagnostic dose of 25 µg/ml at a diagnostic time of 30 min. This diagnostic dose of pirimiphos-methyl was used to monitor pirimphos-methyl susceptibility in Ae. aegypti throughout the trial.
Assuntos
Aedes , Inseticidas , Controle de Mosquitos , Compostos Organotiofosforados , Animais , México , Relação Dose-Resposta a DrogaRESUMO
BACKGROUND: Vector distribution influences arbovirus persistence. This study examined the diversity of mosquito breeding sites in an Atlantic Forest fragment in Rio de Janeiro, Brazil. METHODS: Mosquito specimens were collected at Fazenda dos Cordeiros, Silva Jardim, Brazil. Tire, plastic, bamboo, and sapucaia traps were evaluated for oviposition preferences using ecological indices. RESULTS: Tire traps had the highest density. Bamboo traps showed the highest diversity. Plastic container was the most divergent site. The key recorded vector species included Aedes albopictus and Haemagogus leucocelaenus. CONCLUSIONS: Identifying the breeding sites that contribute the most to mosquito density is essential for optimizing control strategies.
Assuntos
Culicidae , Florestas , Mosquitos Vetores , Densidade Demográfica , Animais , Brasil , Mosquitos Vetores/classificação , Mosquitos Vetores/fisiologia , Culicidae/classificação , Culicidae/fisiologia , Biodiversidade , Feminino , Aedes/fisiologia , Aedes/classificação , Oviposição/fisiologiaRESUMO
Chikungunya virus (CHIKV) is mainly transmitted by the invasive mosquito Aedes (Stegomyia) aegypti in tropical and subtropical regions worldwide. However, genetic adaptations of the virus to the peri domestic mosquito vector Aedes (Stegomyia) albopictus has resulted in enhanced vector competence and associated epidemics and may contribute to further geographic expansion of CHIKV. However, evidence-based data on the relative role of Ae. albopictus in CHIKV transmission dynamics are scarce, especially in regions where Ae. aegypti is the main vector, such as in Brazil. Here, we review the CHIKV genotypes circulating in Brazil, spatial and temporal distribution of Chikungunya cases in Brazil, and susceptibility to infection and transmission (i.e., vector competence) of Ae. albopictus for CHIKV to better understand its relative contribution to the virus transmission dynamics.
Assuntos
Aedes , Febre de Chikungunya , Vírus Chikungunya , Genótipo , Mosquitos Vetores , Análise Espaço-Temporal , Aedes/virologia , Vírus Chikungunya/genética , Brasil/epidemiologia , Febre de Chikungunya/transmissão , Febre de Chikungunya/virologia , Febre de Chikungunya/epidemiologia , Animais , Mosquitos Vetores/virologia , HumanosRESUMO
Introducción: El objetivo de este artículo es exponer la experiencia realizada, discutir los alcances y limitaciones de las aplicaciones informáticas para abordar la vigilancia y control del mosquito Aedes aegypti, destacando el gran avance que implica incorporar tecnología a este tipo de investigaciones referidas al campo de la geografía de la salud. Es por eso, que no nos detendremos aquí, a resumir los resultados de las campañas en cuanto a número de muestras obtenidas o número de muestras positivas, sino que se realizará el análisis desde el punto de vista de la metodología y tecnología implementada en la vigilancia epidemiológica del vector en el departamento de Maldonado-Uruguay. Metodología: Estudio observacional retrospectivo, sobre el uso de aplicaciones informáticas geoespaciales que permiten ingresar información geo-referenciada a través de formularios y cuestionarios. Resultados: Éstas aplicaciones permiten ver en tiempo real la situación de distribución del vector en un mapa y a su vez permite realizar análisis temporales que facilitan la toma de decisión de las autoridades competentes. Conclusión: A través de un sistema de mapeo como herramienta para el análisis y diagnóstico, utilizando el Sistema de Información Geográfica, es posible representar espacialmente los macro factores determinantes de las enfermedades transmitidas por vectores. Esto se logra mediante la elaboración de diversos mapas temáticos que superponen eventos, lo que permite generar un "mapa de riesgo" para el área geográfica de estudio.
Introduction: The objective of this article is to present the experience carried out, discuss the scope and limitations of computer applications to address the surveillance and control of the mosquito Aedes aegypti, highlighting the great progress involved in incorporating technology into this type of research related to the field of health geography. That is why we will not stop here to summarize the results of the campaigns in terms of number of samples obtained or number of positive samples, but rather the analysis will be carried out from the point of view of the methodology and technology implemented in the epidemiological surveillance of the vector in the department of Maldonado-Uruguay . Methodology: Retrospective observational study on the use of geospatial computer applications that allow entering geo-referenced information through forms and questionnaires. Results: These applications allow you to see the vector distribution situation on a map in real time and at the same time allow you to carry out temporal analyzes that facilitate decision making by the competent authorities. Conclusion: Through a mapping system, as a tool for analysis-diagnosis, using the Geographic Information System, it is possible to achieve the spatial representation of determining macrofactors for diseases transmitted by and from the development of various thematic maps with the superposition of events, to constitute a "risk map" of the geographic area of ââstudy
Introdução: O objetivo deste artigo é apresentar a experiência realizada, discutir o alcance e as limitações das aplicações computacionais para abordar a vigilância e controle do mosquito Aedes aegypti, destacando o grande avanço envolvido na incorporação da tecnologia neste tipo de pesquisa relacionada à área. da geografia da saúde. É por isso que não vamos parar aqui para resumir os resultados das campanhas em termos de número de amostras obtidas ou número de amostras positivas, mas sim a análise será realizada do ponto de vista da metodologia e tecnologia implementada na vigilancia epidemiológica do vetor no departamento de Maldonado-Uruguai. Metodologia: Estudo observacional retrospectivo sobre a utilização de aplicações informáticas geoespaciais que permitem inserir informação georreferenciada através de formulários e questionários. Resultados: Estas aplicações permitem visualizar a situação da distribuição vetorial num mapa em tempo real e ao mesmo tempo permitem realizar análises temporais que facilitam a tomada de decisões por parte das autoridades competentes. Conclusão: Através de um sistema de mapeamento, como ferramenta de análise-diagnóstico, utilizando o Sistema de Informação Geográfica, é possível obter a representação espacial de macrofatores determinantes para doenças transmitidas por e a partir da elaboração de diversos mapas temáticos com a superposição de eventos, constituir um "mapa de risco" da área geográfica de estudo.
Assuntos
Aedes , Controle de Vetores de Doenças , Sistemas de Informação Geográfica/instrumentação , Tecnologia da Informação , Vigilância em Saúde Pública/métodos , Mapeamento Geográfico , Uruguai/epidemiologia , Estudos RetrospectivosRESUMO
Objetivo: Evaluar los factores de riesgo a la exposición de virus de dengue en el Municipio Chacao entre enero y marzo de 2024. Método: La población objeto de la presente investigación estuvo conformada por todos los habitantes del municipio Chacao atendidos en los distintos ambulatorios de Salud Chacao durante los meses enero-marzo del año 2024. El presente estudio es una investigación de campo, que utilizó como técnicas de procesamiento las entrevistas estructuradas para la recopilación de datos: el registro, la clasificación y la tabulación de la información aplicada a 50 pacientes del municipio. Resultados: en 50 personas estudiadas: 52 % han estado expuestos siempre o casi siempre a mosquitos, 10 % usa medidas de protección de barrera anti zancudos permanentemente y 28 % ocasionalmente, 42 % tiene aguas estancadas cerca de su vivienda. Conclusiones: Los factores de riesgo a la exposición a virus del dengue, son multifactoriales, incluyen como intrínsecos a edad, factores inmunitarios, falta de higiene, etc. y extrínsecos (ambientales) como: ausencia o incumplimiento de políticas de saneamiento, que trae como consecuencia: estancamiento de aguas, presencia de criaderos, poca o nulas campañas de concientización, etc. La prevención y el control de exposición a virus del dengue requieren un enfoque integral que aborde la acción de planes gubernamentales de control ambiental, la promoción de la salud y la participación comunitaria para reducir la incidencia de esta enfermedad transmitida por mosquitos
Objective: To evaluate the risk factors for exposure to the dengue virus in the Chacao Municipality between January and March 2024. Method: The population object of this investigation was made up of all the inhabitants of the Chacao municipality treated in the different outpatient clinics of Salud Chacao during the months of January-March of 2024. The present study is a field investigation, which was used as techniques processing structured interviews for data collection: registration, classification and tabulation of information applied to 50 patients from the municipality. Conclusions: It is necessary to affirm that the risk factors for contracting dengue are multifactorial and include aspects that range from intrinsic factors (age of the population, immune factors, etc.) to extrinsic factors (water stagnation, lack of hygiene, presence of breeding sites, little or no awareness campaigns, etc.). Dengue prevention and control requires a comprehensive approach that addresses breeding sites elimination, health promotion, and community engagement to reduce the incidence of this mosquito-borne disease.
Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Aedes , Dengue/prevenção & controle , Vírus da Dengue/classificação , Venezuela , Água Estagnada/análise , Controle de Mosquitos , Estudos Transversais , Inquéritos e Questionários , Estudos Retrospectivos , Fatores de Risco , Distribuição por Idade e Sexo , Instituições de Assistência AmbulatorialRESUMO
Aedes aegypti is a mosquito species known for its role in transmitting dengue fever, a viral disease prevalent in tropical and subtropical regions. Recognizable by its white markings and preference for urban habitats, this mosquito breeds in standing water near human dwellings. A promising approach to combat the proliferation of mosquitoes is the use of smart traps, equipped with advanced technologies to attract, capture, and monitor them. The most significant results include 97% accuracy in detecting Aedes aegypti, 100% accuracy in identifying bees, and 90.1% accuracy in classifying butterflies in the laboratory. Field trials successfully validated and identified areas for continued improvement. The integration of technologies such as Internet of Things (IoT), cloud computing, big data, and artificial intelligence has the potential to revolutionize pest control, significantly improving mosquito monitoring and control. The application of machine learning (ML) algorithms and computer vision for the identification and classification of Aedes aegypti is a crucial part of this process. This article proposes the development of a smart trap for selective control of winged insects, combining IoT devices, high-resolution cameras, and advanced ML algorithms for insect detection and classification. The intelligent system features the YOLOv7 algorithm (You Only Look Once v7) that is capable of detecting and counting insects in real time, combined with LoRa/LoRaWan connectivity and IoT system intelligence. This adaptive approach is effective in combating Aedes aegypti mosquitoes in real time.
Assuntos
Aedes , Algoritmos , Controle de Mosquitos , Aedes/fisiologia , Animais , Controle de Mosquitos/métodos , Controle de Mosquitos/instrumentação , Aprendizado de Máquina , Inteligência Artificial , Mosquitos Vetores , Humanos , Dengue/prevenção & controle , Dengue/transmissãoRESUMO
Introduction. Aedes aegypti is an important vector of arboviral diseases like dengue among others. Traditional control strategies, such as the use of insecticides, have lost effectiveness due to the emergence of resistance in mosquito populations. Biological control and fungi applied for biocontrol are presented as viable and ecological alternatives. Objective. To evaluate in vitro pathogenicity of Trichoderma sp. isolates obtained from Urabá (Antioquia) on larvae of Ae. aegypti, and to determine the mean lethal concentration and mean lethal time of the most pathogenic isolate. Materials and methods. Using the sentinel larvae method of Ae. aegypti, fungi were isolated from water bodies in the Urabá region (Antioquia). The isolates were characterized morphologically and molecularly to determine their taxonomic identity. Pathogenicity tests were performed in vitro on Ae. aegypti larvae in the L2/L3 stages. Subsequently, a strain was selected to establish its mean lethal concentration and mean lethal time. Results. Trichoderma sp. strain AP-91 caused high mortality in larval populations of Ae. aegypti. We estimated a mean lethal concentration of 1.8 × 107 conidia/ml and a mean lethal time of 20.67 hours. Conclusion. The strain AP-91 showed potential for its use as biological control of Ae. aegypti, making it a suitable candidate for scale-up cultures applied to integrated vector management. This research suggests exploring compounds and enzymes produced by the AP-91 strain to understand better its pathogenicity.
Introducción. Aedes aegypti es un vector importante de enfermedades arbovirales como el dengue, entre otras. Las estrategias tradicionales de control, como el uso de insecticidas, han perdido eficacia debido a la aparición de resistencia en las poblaciones de mosquitos. El control biológico y el uso de hongos biocontroladores se presentan como alternativas viables y amigables con el medio ambiente. Objetivo. Evaluar la patogenicidad in vitro de aislamientos del género Trichoderma -obtenidos del Urabá antioqueño- sobre larvas de Ae. aegypti, y determinar la concentración letal media (CL50) y el tiempo letal medio (TL50) del más patógeno. Materiales y métodos. Mediante el método de larvas centinelas con especímenes de Ae. aegypti, se logró aislar hongos de cuerpos de agua de la región del Urabá (Antioquia). Los aislamientos se caracterizaron a nivel morfológico y molecular, para determinar su identidad taxonómica. Se llevaron a cabo pruebas de patogenicidad in vitro utilizando larvas de Ae. aegypti en los estadios L2 y L3. Posteriormente, se seleccionó una cepa para determinar su concentración letal media y tiempo letal medio. Resultados. La cepa AP-91 de Trichoderma sp. causó porcentajes altos de mortalidad en poblaciones de larvas de Ae. aegypti. Se obtuvo una concentración letal media de 1,8 × 107 conidios/ml y un tiempo letal medio de 20,67 horas. Conclusión. La cepa AP-91 tiene potencial para el control biológico de Ae. aegypti y puede ser una candidata idónea para usar en el manejo integrado de vectores mediante su cultivo escalado. La investigación sugiere explorar los compuestos y enzimas producidos por esta cepa para comprender mejor su patogenicidad.
Assuntos
Aedes , Larva , Animais , Aedes/microbiologia , Larva/microbiologia , Colômbia , Controle Biológico de Vetores , Trichoderma/patogenicidade , Trichoderma/fisiologia , Controle de Mosquitos/métodos , Mosquitos Vetores/microbiologiaRESUMO
BACKGROUND: Dengue is an emerging disease in Argentina due to the colonization of Aedes aegypti, the mosquito vector. Buenos Aires Province is the biggest and most populated district in Argentina, suffering dengue outbreaks of growing magnitude. During epidemic periods, pyrethroid insecticides are used in this country to control adult mosquitoes. Pyrethroid resistance in dengue vectors has been reported worldwide, making it necessary to implement resistance management strategies. The voltage-gated sodium channel is the target site of pyrethroids. Mutations in the gene encoding this protein, called kdr mutations, are usually the molecular cause of pyrethroid resistance in insects. In Ae. aegypti from the Americas, three kdr substitutions were described: V410L, V1016I, and F1534C. The diagnostic of kdr mutations is recommended for the early detection of pyrethroid resistance as well as the consequent planning of evidence-based control policies. METHODS: We distributed ovitraps across 16 localities in Buenos Aires Province, collecting 22,123 eggs. A total of 522 mosquitoes were genotyped in positions 1016 and 1534 of voltage-gated channel using multiplex high-resolution melting and/or TaqMan probe methods. A subset of 449 samples was also genotyped by a singleplex high-resolution melting method developed ad hoc and/or Sanger sequencing. RESULTS: We have documented, for the first time to our knowledge in the central region of Argentina, the presence of the 1016Ikdr + 1534Ckdr allele. Additionally, our study reports the first identification of the V410L mutation in central Argentina. These results underscore a growing trend of pyrethroid resistance in Ae. aegypti, fueled by the widespread use of these insecticides. CONCLUSIONS: We detected 1016Ikdr + 1534Ckdr and 410Lkdr mutations in central Argentina for the first time and improved the processivity and accuracy of kdr genotyping methods. The results are both a tool for resistance monitoring and a sign of alarm to direct efforts towards finding sustainable methods for vector control to complement or replace pyrethroids. Joint efforts between academia and authorities to develop and implement public policies for vector control are a productive way to transfer scientific results for their application in public health.
Assuntos
Aedes , Genótipo , Resistência a Inseticidas , Inseticidas , Mosquitos Vetores , Mutação , Piretrinas , Canais de Sódio Disparados por Voltagem , Animais , Aedes/genética , Aedes/efeitos dos fármacos , Piretrinas/farmacologia , Resistência a Inseticidas/genética , Argentina , Inseticidas/farmacologia , Mosquitos Vetores/genética , Mosquitos Vetores/efeitos dos fármacos , Canais de Sódio Disparados por Voltagem/genética , Dengue/transmissão , Proteínas de Insetos/genética , FemininoRESUMO
The global spread of Aedes aegypti and the associated public health risk have stimulated the development of several mathematical models to predict population dynamics in response to biological or environmental changes in real, future, or simulated scenarios. The aim of this study is to identify published articles on differential equation-based population dynamics models of Aedes aegypti, highlight their differences and commonalities, and examine their application in surveillance and control programs. Following the PRISMA guidelines, a systematic review was conducted in seven electronic databases (Scopus, PUBMED, IEEE Xplore, Science Direct, DOAJ, Scielo, and Google Scholar), with the last update on 8 February 2023. The initial search yielded 513 studies, of which 31 were finally selected. The articles analyzed showed great variability in the equations, processes, and variables included, with temperature being the most common environmental factor. Only a few models incorporated spatial heterogeneity or validation methods. Our findings suggest that improving the generation of temporal and spatially explicit forecasts through interdisciplinary collaboration, the use of new technologies, and validation with field data is essential for these models to effectively support public health efforts. Differential equation-based population dynamics models offer valuable insights and could greatly benefit mosquito surveillance programs if standardized and tailored to relevant scales.
Assuntos
Aedes , Mosquitos Vetores , Dinâmica Populacional , Aedes/fisiologia , Aedes/crescimento & desenvolvimento , Animais , Mosquitos Vetores/fisiologia , Mosquitos Vetores/crescimento & desenvolvimento , Modelos Teóricos , Modelos Biológicos , Dengue/epidemiologia , Dengue/transmissão , Dengue/prevenção & controleRESUMO
Aedes albopictus (Skuse) is a competent vector of dengue and Zika viruses in Mexico. Monitoring the level of resistance of local population is essential due to its epidemiological significance. This study aimed to identify mutations in the voltage-gated sodium channel (VGSC) as one of the mechanisms responsible for pyrethroid insecticide resistance in Ae. albopictus. Immature samples were collected in a rural town in Yucatan, Mexico, from May to October 2021. The pyrethroid insecticide lambda-cyhalothrin was impregnated in CDC bottles and bioassays were conducted on Ae. albopictus populations 3-5 days after emergence. The mosquitoes were susceptible to the insecticide. Females were taken for total DNA extraction. Fragments of domains II, III, and IV of the voltage-gated sodium channel (VGSC) were amplified and sequenced. The presence of synonymous and non-synonymous mutations was found in positions 1532 and 1534 of domain III of the sodium channel gene (VGSC). No mutant alleles in domain IV were detected. A homozygous mutant (ACG) coding for the amino acid threonine (1008Thr) was identified in domain II. Domain III included three heterozygous alleles (P1528S, L1530S, and Ile1410Thr). This last heterozygous allele is reported for the first time in Mexico. Homozygous mutants encoding the amino acids serine/serine and serine/proline in domain III were observed. These have been reported in Aedes aegypti from Mexico, but not yet in Ae. albopictus. This represents new findings for the region, as Ae. albopictus has only been introduced there for approximately five years. In conclusion, non-synonymous mutations were found in Ae. albopictus in a rural area of Yucatan, emphasizing the importance of integrated vector control to prevent Asian tiger mosquitoes from spreading these resistant alleles.
Assuntos
Aedes , Resistência a Inseticidas , Inseticidas , Mutação , Piretrinas , Canais de Sódio Disparados por Voltagem , Animais , Aedes/genética , Aedes/efeitos dos fármacos , Resistência a Inseticidas/genética , Piretrinas/farmacologia , Canais de Sódio Disparados por Voltagem/genética , México , Feminino , Inseticidas/farmacologia , Mosquitos Vetores/genética , Mosquitos Vetores/efeitos dos fármacos , Nitrilas/farmacologiaRESUMO
Estimating the abundance of immature mosquitoes in discarded water-filled tyres is a laborious task due to their shape and size. Our objective was to develop a procedure that allows, by counting individuals in a water sample, to estimate their total abundance. Polynomial functions linking water column height and water volume were fitted for five tyre categories (from cars to tractors) and horizontal/vertical storage positions. A total of 358 discarded water-filled tyres were then surveyed using this method in 16 piles of tyres in temperate Argentina. Tyre capacity was greater in vertical than horizontal position, reaching a maximum of 95.6 L in tractor tyres. In contrast, the volume of water retained under field conditions showed the opposite pattern, being greater in horizontal tyres. Water volume increased significantly across tyre categories in both horizontal (J-T = 7306, p < 0.001) and vertical (J-T = 10,792, p < 0.001) positions. Most infested tyres (n = 150) showed low abundances and a few extremely high values, both for all mosquito species grouped and for Culex pipiens and Aedes aegypti separately. The median abundance of mosquitoes per infested tyre was 35, decreasing to 30 for Cx. pipiens and 17 for Ae. aegypti. These values ââincreased significantly across tyre categories for mosquitoes (J-T = 5525, p < 0.001) and Cx. pipiens (J-T = 2275, p < 0.05), but not for Ae. aegypti (J-T = 1526, p = 0.472). The comparison between vertical and horizontal positions was not significant for both vector species. Our methodological approach could be particularly useful in research addressing the assessment of disease risk associated with mosquito productivity.
Assuntos
Aedes , Culex , Animais , Culex/classificação , Culex/fisiologia , Aedes/fisiologia , Aedes/classificação , Argentina , Densidade Demográfica , Água/parasitologia , Mosquitos Vetores/fisiologia , Entomologia/métodosRESUMO
Aedes aegypti (Diptera: Culicidae) is the primary arthropod vector responsible for the transmission of dengue, which is present in more than one hundred countries. The application of synthetic larvicides is one of the most common strategies used for dengue control, but their prolonged use can cause larvicide resistance or tolerance, environmental damage, and have toxic effects on human and animal health. Thus, faced with this problem, there have been increasing efforts to find alternative larvicides against Ae. Aegypti. This search has been mainly focused on naturally occurring chemical compounds, driven by the evidence of their potential effectiveness, and by a desire to find more sustainable, environmentally friendly, and safe alternatives to synthetic larvicides. Thus, the present study aimed to review the effects of terpenes and their derivatives on mortality of the Ae. aegypti larvae, focusing mainly on a lethal concentration of 50% (LC50), in addition to summarizing information on its mechanisms of action and effects on non-target organisms. We searched the main databases for studies published up to April 2024 using relevant keywords, and data were extracted and analyzed qualitatively and quantitatively. Twenty-one articles describing 69 different terpenes and derivatives met the criteria of the review and meta-analysis. Among them, 76.8% were terpenoids and 23.2% terpenes. The LC50 ranged from 0.4 to 1628.2 ppm. The present review and meta-analysis showed that the terpenes and terpenoids can be promising chemical templates for use in eco-friendly larvicides against Ae. aegypti.
Assuntos
Aedes , Inseticidas , Larva , Terpenos , Aedes/efeitos dos fármacos , Animais , Terpenos/farmacologia , Larva/efeitos dos fármacos , Controle de Mosquitos/métodos , Mosquitos Vetores/efeitos dos fármacosRESUMO
Large-scale epidemics of arboviruses, such as dengue, have heightened societal awareness regarding the necessity of combating the primary transmission vectors. Equally critical is the identification of environmental conditions and variables that influence vector population dynamics. Aedes aegypti, the primary vector of arboviruses such as dengue and Zika in Brazil, is closely associated with the climatic and geographical conditions of urban environments. This study examines the relationship between precipitation and confirmed dengue cases in Recife (Brazil), employing regression and quantile analyses to evaluate the influence of meteorological conditions on the disease's spread. The findings reveal a direct correlation between monthly averages of precipitation and confirmed cases, although this is apparent only when excluding years of epidemic peaks. The highest number of cases generally aligns with the rainy season, and the lowest with the dry season, with weak, moderate and strong precipitation events being closely linked to increased dengue incidence. However, notable discrepancies were identified: four out of six major outbreaks occurred in drier months, challenging the assumption of a straightforward relationship between rainfall and dengue incidence. These findings underscore the multifaceted nature of dengue dynamics, suggesting that while precipitation plays a significant role, other factors, including serotype circulation and broader climatic phenomena, are equally critical in driving outbreaks. This complexity highlights the need for a more comprehensive understanding of the mechanisms influencing dengue epidemics.
Assuntos
Aedes , Clima , Dengue , Mosquitos Vetores , Chuva , Dengue/epidemiologia , Brasil/epidemiologia , Humanos , Aedes/virologia , Animais , Saúde Pública , Incidência , Cidades/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Estações do AnoRESUMO
Background: Dengue fever, transmitted by Aedes aegypti and Aedes albopictus mosquitoes, poses a significant public health challenge in tropical and subtropical regions. Dengue surveillance involves monitoring the incidence, distribution, and trends of infections through systematic data collection, analysis, interpretation, and dissemination. It supports public health decision-making, guiding interventions like vector control, vaccination campaigns, and public education. Objective: Herein, we report the development of a surveillance system already in use to support public health managers against dengue transmission in Foz do Iguaçu, a dengue-endemic Brazilian city located in the Triple Border with Argentina and Paraguay. Methods: We present data encompassing the fieldwork organization of more than 100 health agents; epidemiological and entomological data were gathered from November 2022 to April 2024, totalizing 18 months of data collection. Results: By registering health agents, we were able to provide support for those facing issues to fill their daily milestone of inspecting 16 traps per working day. We filtered dengue transmission in the city by patient age, gender, and reporting units, as well as according to dengue virus serotype. The entomological indices presented a strong seasonal pattern, as expected. Several longtime established routines in Foz do Iguaçu have been directly impacted by the adoption of Vigilância Integrada com Tecnologia (VITEC). Conclusions: The implementation of VITEC has enabled more efficient and accurate diagnostics of local transmission risk, leading to a better understanding of operational activity patterns and risks. Lately, local public health managers can easily identify hot spots of dengue transmission and optimize interventions toward those highly sensitive areas.