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Identification of Aedes aegypti breeding hotspots is essential for the implementation of targeted vector control strategies and thus the prevention of several mosquito-borne diseases worldwide. Training computer vision models on satellite and street view imagery in the municipality of Rio de Janeiro, we analyzed the correlation between the density of common breeding grounds and Aedes aegypti infestation measured by ovitraps on a monthly basis between 2019 and 2022. Our findings emphasized the significance (p ≤ 0.05) of micro-habitat proxies generated through object detection, allowing to explain high spatial variance in urban abundance of Aedes aegypti immatures. Water tanks, non-mounted car tires, plastic bags, potted plants, and storm drains positively correlated with Aedes aegypti egg and larva counts considering a 1000 m mosquito flight range buffer around 2700 ovitrap locations, while dumpsters, small trash bins, and large trash bins exhibited a negative association. This complementary application of satellite and street view imagery opens the pathway for high-resolution interpolation of entomological surveillance data and has the potential to optimize vector control strategies. Consequently it supports the mitigation of emerging infectious diseases transmitted by Aedes aegypti, such as dengue, chikungunya, and Zika, which cause thousands of deaths each year.

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It is estimated that there are over 500 species of arboviruses worldwide, with more than 150 of them directly associated with human diseases, the majority of which are zoonotic. Among the main arboviruses circulating in Brazil, dengue, Zika, and chikungunya stand out, all transmitted through a common vector, Aedes aegypti. Given this scenario, the development and implementation of more efficient surveillance strategies become urgent. This study aims to compare and evaluate the efficiency of beetroot peel, Beta vulgaris, as an attractant for Ae. aegypti oviposition under field conditions in the municipality of Agrestina, State of Pernambuco, Brazil. Beetroot peel extract is a cheap and accessible source of geosmin, which holds significant potential as an attractant for mosquitoes due to its resemblance to microbial volatiles found in water bodies rich in organic material. During the study period (November 2023 to April 2024), 40 traps were set in each neighborhood, with 20 of each attractant. Two traps were used per property, one following the traditionally used model (beer yeast infusion) and another containing beetroot peel. Overall, in both analyzed neighborhoods (Campo Novo and Cohab), beetroot peel appeared to be a more efficient attractant for the oviposition of culicids. Beetroot peel showed the highest values in egg abundance and in the analyzed indices.

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Culicid species, which include potential vectors of yellow fever, are diverse and abundant, with species commonly co-occurring in certain sites. Studying these species can provide important insights into their vector potential and, consequently, epizootic cycles of arboviruses carried about by these vectors. Here, we evaluated the vertical distribution and temporal segregation of mosquito oviposition with emphasis on arbovirus vectors in a fragment of the Atlantic Forest in Casimiro de Abreu, Rio de Janeiro, Brazil. Two sampling points were selected: Fazenda Três Montes and the Reserva Natural de Propriedade Privada Morro Grande. Collections were carried out at two sites using 10 ovitraps installed on the vegetation cover at different heights (0, 2, 4, 6, and 8 m above ground level) and monitored monthly from July 2018 to December 2020. The hypotheses of temporal and vertical stratification were tested through a PERMANOVA, and the relationship of each species with the vertical distribution was evaluated individually through a correlation analysis. We collected a total of 3075 eggs, including four species of medical importance: Haemagogus leucocelaenus (n = 1513), Haemagogus janthinomys (n = 16), Aedes albopictus (n = 1097), and Aedes terrens (n = 449). We found that Hg. leucocelaenus had a positive relationship with height, exhibiting behavior that appears to benefit from higher heights. The abundance of Ae. terrens seemed to follow Hg. leucocelaenus, although we did not find a relationship with height for the former species. On the other hand, Ae. albopictus exhibited a negative relationship with height, becoming absent or outnumbered at higher strata. Our study site has already presented evidence of recent transmission of the wild yellow fever virus, supporting the need to carefully monitor the emergence of febrile diseases among residents in the surrounding areas and the local population.

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Ovitraps can detect Aedes vectors at an early stage and can serve as an alarm indicator for outbreak prediction. This study aimed to summarize the available literature about the ovitrap system and to determine its feasibility, required resources and costs when installing and maintaining this vector surveillance system in the municipality of Los Patios, Colombia. A scoping review to assess the role of ovitraps as a tool for Aedes vector surveillance was conducted. The subsequent fieldwork consisted of mapping the municipality, manufacturing, and installing 40 ovitraps in 10 blocks, revising them weekly for 4 weeks by two half-time employed vector control technicians, and carrying out a cost analysis. A total of 38 studies were included in this review showing that ovitraps had a better performance than other entomological surveillance methods and a positive correlation with other entomological and disease variables. From the field results over 4 weeks, a high proportion of positive ovitraps (80%, 90%, 75%, 97.5%) and positive blocks (100%) as well as a good acceptance by house owners (76.9%), were identified. Operational indicators such as average installation time of the ovitraps (10h15 m), weekly reading and reinstallation (on average 7h27 m) and the cost of the intervention (COL$1,142,304.47/US$297) were calculated. Literature shows that ovitraps are sensitive to detect the presence of Aedes mosquitoes, providing data efficiently and timely for outbreak prediction. The field testing showed it is an affordable and feasible method in the context of a Colombian municipality and similar endemic areas.

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Entomological surveillance is a traditional method to measure presence, distribution, and seasonal variation of vectors in urban areas, and is essential to targeted control activities to prevent arbovirus transmission. Ovitraps as one of the main components of surveillance programs, enable determination of female oviposition behavior, as well as identification of seasonal variations of the vector. The goals of this study were 1) to detect the mosquitos (Aedes aegypti Linnaeus) and (Aedes albopictus Skuse) (Diptera:Culicidae), in Paranaguá city, 2) to assess ovitrap positive index (OPI), egg density index (EDI), and their relationship with meteorological variables, and 3) to evaluate the vertical transmission of dengue, Zika, and chikungunya in Ae. aegypti and Ae. albopictus. The study was carried out in urban areas of Paranaguá city, an important port region of Brazil, from June 2017 to November 2018. The city was divided into 16 area-clusters. Three-hundred and thirty-one ovitraps were installed monthly, remaining for four days in selected places. Kernel density maps were done to compare the spatiotemporal distribution of collected eggs. Areas which maintained constant oviposition associated with vector activity were identified and were found to overlap the area-clusters with the highest EDI. As viral RNA was not detected, vertical transmission was likely not a maintenance mechanism of arbovirus circulation in Ae. aegypti and Ae. albopictus vectors. This study reiterates the importance, efficiency, and feasibility of ovitraps to monitor the presence and dynamics of Aedes spp. populations.

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Mosquitoes and the diseases they transmit continue to place millions of people at risk of infection around the world. Novel methods of vector control are being developed to provide public health officials with the necessary tools to prevent disease transmission and reduce local mosquito populations. However, these methods will require public acceptance for a sustainable approach and evaluations at local settings. We present our efforts in community engagement carried out in colonias of the Lower Rio Grande Valley in south Texas for mosquito surveillance, control, and ecological projects. Along the US-Mexico border the term colonia refers to impoverished communities that are usually inhabited by families of Hispanic heritage. The different engagements were carried out from September 2016 to February 2019; during this time, we had three distinct phases for community engagement. In Phase 1 we show the initial approach to the colonias in which we assessed security and willingness to participate; in Phase 2 we carried out the first recruitment procedure involving community meetings and house-to-house recruitment; and in Phase 3 we conducted a modified recruitment procedure based on community members' input. Our findings show that incorporating community members in the development of communication materials and following their suggestions for engagement allowed us to generate culturally sensitive recruitment materials and to better understand the social relationships and power dynamics within these communities. We were able to effectively reach a larger portion of the community and decrease the dropout rate of participants. Progress gained with building trust in the communities allowed us to convey participant risks and benefits of collaborating with our research projects. Community engagement should be viewed as a key component of any local vector control program as well as for any scientific research project related to vector control. Even in the face of budgetary constraints, small efforts in community engagement go a long way.

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Aedes aegypti is the main vector of dengue in the Americas and is also a transmitter of urban yellow fever arboviruses, Zika, and Chikungunya, all of which have substantial economic impacts on the affected countries. Through mathematical models, the influence of climatic factors on the oviposition of Ae. aegypti was determined. The data were collected in the city of Apucarana, Paraná State, using oviposition traps. Daily data were submitted to a negative binomial regression model (p < 0.05). The analyses were performed using the R statistical program to determine the climatic factors that most influenced oviposition. A Poisson regression showed that the variables temperature, atmospheric pressure, humidity, and precipitation significantly increased the number of eggs. However, using the semi-normal probability graph with a simulation envelope, it was determined that the Poisson regression model was not adequate to explain the relationships between the variables. Thus, a negative binomial regression model was used, which overcame the problem of overdispersion, and showed that only temperature affected the increase in the number of eggs, where an increase of 1 °C was expected to result in a 54.03% increase in the number of Ae. aegypti eggs.

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The presence and establishment of Culicidae in urban areas increase the transmissibility of tropical diseases, since some species can participate as vectors of pathogens. Thus, this study aimed to evaluate the indoor and outdoor abundance of immature and adult populations of Culicidae at the urban area of Porto Velho, Rondônia. Mosquitoes were captured using electric aspirators and ovitraps in September and December 2018 in 27 households spread over nine neighborhoods. A total of 2,342 specimens were collected, distributed among five species, of which Culex quinquefasciatus (Say, 1823), Aedes aegypti (Linnaeus, 1762) and Aedes albopictus (Skuse, 1894) were the most abundant. Considering the sum total obtained by both techniques, more mosquitoes were captured indoors than outdoors. However, the GLM estimates for the ovitrap technique showed that immature Ae. aegypti, Ae. albopictus and Cx. quinquefasciatus were significantly more abundant in the outdoors, on average. The opposite result was observed for electrical aspiration, in which Ae. aegypti and Cx. quinquefasciatus adults were more abundant indoors. The average number of winged Ae. albopictus showed no significant difference between indoors and outdoors. Our findings corroborate the data on the abundance and incidence of these three species in other regions of Brazil, highlighting the need for continuous surveillance due to their importance in disease transmission to humans. We also demonstrated that the ovitrap is a sensitive device to monitor Cx. quinquefasciatus larvae and wild species that occasionally frequent urban areas, and thus can be used for surveillance, especially when there are budgetary constraints. Therefore, we emphasize that the combination of techniques, in addition to identifying which species and which stage of development are more frequent inside and outside households, also allows for the implementation of specific and integrated control measures.

A presença e o estabelecimento de culicídeos na área urbana aumentam a transmissibilidade de doenças tropicais, pois algumas espécies podem participar como vetores de patógenos. Assim, este estudo teve como objetivo avaliar a abundância de populações imaturas e adultas de espécies de culicídeos em intradomicílio e peridomicílio, em localidades da área urbana de Porto Velho, Rondônia. Os mosquitos foram capturados com o uso de aspiradores elétricos e ovitrampas nos meses de setembro e dezembro de 2018 em 27 residências distribuídas por nove bairros. Coletaram-se 2.342 espécimes, distribuídos em cinco espécies, das quais Culex quinquefasciatus (Say, 1823), Aedes aegypti (Linnaeus, 1762) e Aedes albopictus (Skuse, 1894) foram as mais abundantes. Considerando o somatório obtido por ambas as técnicas, mais mosquitos foram capturados no intradomicílio que no peridomicílio. No entanto, as estimativas de GLM para a técnica de ovitrampa demonstraram que imaturos de Ae. aegypti, Ae. albopictus e Cx. quinquefasciatus foram significativamente mais abundantes em peridomicílio, em média. Resultado inverso foi observado para aspiração elétrica, no qual adultos de Ae. aegypti e Cx. quinquefasciatus foram mais abundantes em intradomicílio. O número médio de adultos de Ae. albopictus não apresentou diferença significativa entre intra e peridomicílio. Nossos achados corroboram os dados de abundância e ocorrência dessas três espécies em outras regiões do Brasil, evidenciando a necessidade de vigilância contínua devido à sua importância na transmissão de doenças aos seres humanos. Nós demonstramos também que a ovitrampa é uma técnica sensível para monitorar larvas de Cx. quinquefasciatus e espécies silvestres que ocasionalmente frequentam áreas urbanas, podendo assim, ser empregada para a vigilância, especialmente quando há restrições orçamentárias. Assim, ressaltamos que a combinação de técnicas, além de identificar quais espécies e qual fase de desenvolvimento são mais frequentes dentro e fora dos domicílios, permite também estabelecer a implementação de medidas de controle específicas e integradas.

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Mosquitoes transmit several pathogens in tropical regions, especially in forest areas. The diseases caused by these pathogens include malaria and several arboviruses such as yellow fever. Brazil has the largest endemic area in the world for yellow fever. Many factors can affect the sylvatic cycle of the disease, shifting it into human-inhabited areas. This study aims to examine the oviposition behavior of mosquito species that are effective or potential vectors of the yellow fever virus and which colonize bamboo traps and ovitraps installed at different heights. The positions of the traps in the strata were changed every 15 days. The collection of immature stages (eggs, larvae, and pupae) was performed every 2 weeks for 12 months from August 2018 to July 2019 in the city of Nova Iguaçu, state of Rio de Janeiro, Brazil, in an area near the Tinguá Biological Reserve (REBIO) in the districts of Adrianópolis and Rio D'ouro. Statistical tests were used to compare oviposition at each stratum, and correlation tests showed the relationship between the presence of eggs and immature mosquitoes (larvae and pupae) and temperature, precipitation, and trap type. The diversity was calculated for each trap type and height, as well as the dry and rainy seasons. During the sampling period, 3929 eggs and 4953 larvae and pupae were collected. The traps installed in the high strata remained empty when traps on the ground were installed at the same time, although not when they were installed on their own. The results obtained with this new proposed methodology suggest that diversity is greatest in the rainy season and in bamboo traps for either stratum. Furthermore, this study suggests that mosquitoes begin searching for breeding sites at ground level. Higher levels may be occupied due to the absence or impermanence of other breeding sites.

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OBJECTIVES: Understanding the intra-urban spatial dynamics of Aedes aegypti and dengue transmission is important to effectively guide vector control. Ovitraps are a sensitive, cost-effective vector surveillance tool, yet few longitudinal studies have evaluated ovitrap indices and dengue occurrence. We aimed to assess the spatial patterns of dengue incidence and Ae. aegypti ovitrap positivity index (OPI) over time and to examine the spatial relationship between these two variables. METHODS: This study used 12 years (2007-2018) of dengue case records and biweekly Ae. aegypti ovitrap data in Belo Horizonte, Brazil. We aggregated data by year and health centre catchment area (n = 152) and used both univariate and bivariate global Moran's I statistic and LISA to evaluate spatial clustering. RESULTS: Annual dengue incidence ranged from 18 to 6262/100 000 residents and displayed spatial autocorrelation in 10/12 years, with shifting areas of high incidence. Annual OPI ranged from 35.7 to 47.6% and was clustered in all study years, but unlike dengue had consistent spatial patterns over time. Bivariate analysis found both positive (6/12 years) and negative (1/12 years) spatial associations between the two variables. CONCLUSIONS: Low detected presence of Ae. aegypti was not a limiting factor in dengue transmission. However, stable spatial distribution of OPI suggests that certain areas may have persistent breeding sites. Future research should identify factors related to persistent Ae. aegypti hotspots to better guide vector management. Vector control efforts should be paired with additional data on population immunity, circulating serotypes and urban factors to better predict and control outbreaks.

OBJECTIFS: La compréhension de la dynamique spatiale intra-urbaine d'Aedes aegypti et de la transmission de la dengue est importante pour guider efficacement la lutte antivectorielle. Les ovitraps sont un outil de surveillance des vecteurs sensible et rentable, mais peu d'études longitudinales ont évalué les indices d'ovitrap et l'occurrence de la dengue. Nous visions à évaluer les modèles spatiaux de l'incidence de la dengue et de l'indice de positivité d'ovitrap (OPI) d'Ae. aegypti au fil du temps, et à examiner la relation spatiale entre ces deux variables. MÉTHODES: Cette étude a utilisé des dossiers de cas de dengue et des données bihebdomadaires d'ovitrap Ae. aegypti sur 12 ans (2007-2018) à Belo Horizonte, au Brésil. Nous avons agrégé les données par année et par zone d'étude du centre de santé (n = 152) et avons utilisé à la fois la statistique I globale de Moran univariée et bivariée et LISA pour évaluer le regroupement spatial. RÉSULTATS: L'incidence annuelle de la dengue variait de 18 à 6.262/100.000 habitants et affichait une autocorrélation spatiale en 10/12 ans, avec des zones de déplacement de forte incidence. L'OPI annuel variait de 35,7 à 47,6% et était groupé dans toutes les années d'étude, mais contrairement à la dengue, il avait des modèles spatiaux consistents au fil du temps. Une analyse bivariée a trouvé des associations spatiales positives (6/12 ans) et négatives (1/12 ans) entre les deux variables. CONCLUSIONS: La détection d'une faible présence d'Ae. aegypti n'était pas un facteur limitant de la transmission de la dengue. Cependant, la distribution spatiale stable de l'OPI suggère que certaines zones peuvent avoir des sites de reproduction persistants. Les recherches futures devraient identifier les facteurs liés à des hotspots persistants d'Ae. aegypti pour mieux guider la gestion des vecteurs. Les efforts de lutte antivectorielle devraient être associés à des données supplémentaires sur l'immunité de la population, les sérotypes circulants et les facteurs urbains pour mieux prévoir et contrôler les flambées.

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BACKGROUND: Argentina is located at the southern temperate range of arboviral transmission by the mosquito Aedes aegypti and has experienced a rapid increase in disease transmission in recent years. Here we present findings from an entomological surveillance study that began in Córdoba, Argentina, following the emergence of dengue in 2009. METHODS: From 2009 to 2017, larval surveys were conducted monthly, from November to May, in 600 randomly selected households distributed across the city. From 2009 to 2013, ovitraps (n = 177) were sampled weekly to monitor the oviposition activity of Ae. aegypti. We explored seasonal and interannual dynamics of entomological variables and dengue transmission. Cross correlation analysis was used to identify significant lag periods. RESULTS: Aedes aegypti were detected over the entire study period, and abundance peaked during the summer months (January to March). We identified a considerable increase in the proportion of homes with juvenile Ae. aegypti over the study period (from 5.7% of homes in 2009-10 to 15.4% of homes in 2016-17). Aedes aegypti eggs per ovitrap and larval abundance were positively associated with temperature in the same month. Autochthonous dengue transmission peaked in April, following a peak in imported dengue cases in March; autochthonous dengue was not positively associated with vector or climate variables. CONCLUSIONS: This longitudinal study provides insights into the complex dynamics of arbovirus transmission and vector populations in a temperate region of arbovirus emergence. Our findings suggest that Córdoba is well suited for arbovirus disease transmission, given the stable and abundant vector populations. Further studies are needed to better understand the role of regional human movement.

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Resumen: Objetivo: Evaluar el efecto de la combinación de Metarhizium anisopliae y Gliocladium virens, ambos con Aqua Reslin Super, sobre oviposición, eclosión y emergencia de Aedes aegypti. Material y métodos: Se realizaron evaluaciones para determinar el efecto de los tratamientos impregnados en papel filtro y expuestos dentro de recipientes de plástico sobre la oviposición, eclosión y emergencia de Aedes aegypti. Resultados: Los resultados indicaron que las combinaciones hongo e insecticida no afectaron el comportamiento de oviposición, pero sí la eclosión de los huevos y la emergencia del adulto. Conclusión: Con los resultados se puede concluir que la combinación de hongos + insecticida puede ser una buena opción para aplicarse en sitios de oviposición con miras al desarrollo de una ovitrampa letal.

Abstract: Objective: To evaluate the effect of the combination of Metarhizium anisopliae and Gliocladium virens, both with Aqua Reslin Super, on the oviposition, hatching and emergence of Aedes aegypti. Materials and methods: Evaluations were carried out to determine the effect of treatments impregnated on filter paper and exposed within plastic containers on the oviposition, hatching and emergency of Aedes aegypti. Results: The results indicated that the fungus and insecticide combinations did not affect the oviposition behavior, but if the hatching of the eggs and the adult's emergency. Conclusion: With the results it can be concluded that the combination of fungi + insecticide can be a good option to be applied in oviposition sites with a view to the development of a lethal ovitrap.

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OBJECTIVE: To evaluate the effect of the combination of Metarhizium anisopliae and Gliocladium virens, both with Aqua Reslin Super, on the oviposition, hatching and emergence of Aedes aegypti. MATERIALS AND METHODS: Evaluations were carried out to determine the effect of treatments impregnated on filter paper and exposed within plastic containers on the oviposition, hatching and emergency of Aedes aegypti. RESULTS: The results indicated that the fungus and insecticide combinations did not affect the oviposition behavior, but if the hatching of the eggs and the adult's emergency. CONCLUSIONS: With the results it can be concluded that the combination of fungi + insecticide can be a good option to be applied in oviposition sites with a view to the development of a lethal ovitrap.

OBJETIVO: Evaluar el efecto de la combinación de Metarhizium anisopliae y Gliocladium virens, ambos con Aqua Reslin Super, sobre oviposición, eclosión y emergencia de Aedes aegypti. MATERIAL Y MÉTODOS: Se realizaron evaluaciones para determinar el efecto de los tratamientos impregnados en papel filtro y expuestos dentro de recipientes de plástico sobre la oviposición, eclosión y emergencia de Aedes aegypti. RESULTADOS: Los resultados indicaron que las combinaciones hongo e insecticida no afectaron el comportamiento de oviposición, pero sí la eclosión de los huevos y la emergencia del adulto. CONCLUSIONES: Con los resultados se puede concluir que la combinación de hongos + insecticida puede ser una buena opción para aplicarse en sitios de oviposición con miras al desarrollo de una ovitrampa letal.

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In the past decade, new strategies have been developed to control the Aedes aegypti (Diptera: Culicidae) mosquito vector, as well as a broad range of arboviral agents. Vector control surveillance programmes in Puerto Rico and Australia have implemented the Centers for Disease Control and Prevention autocidal gravid ovitrap (AGO), which has had an impact on vector density and, consequently, the epidemiology of arboviral infections. Colombia intends to establish the AGO as a new tool for the surveillance and control of the A. aegypti vector. AGOs were evaluated in a hyperendemic area for dengue virus during an 8-week period in Villavicencio city, eastern Colombia. The results indicated that the AGOs detect a high density of A. aegypti, with positive results for these traps of over 80% and an average catch of six individuals per trap per week. Acceptance of AGOs in the community exceeded 95%, and adherence was around 89%. This study's results demonstrate, for the first time in Colombia, that traps are a useful tool for the surveillance of A. aegypti. Future studies must consider the implementation of AGOs in the region.

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Deployment of Aedes aegypti mosquitoes carrying the endosymbiont bacterium Wolbachia has been identified as a promising strategy to reduce dengue, chikungunya, and Zika transmission. We investigated whether sampling larvae from ovitraps can provide reliable estimates on Wolbachia frequency during releases, as compared to the expensive adult-based BG-Sentinel. We conducted pilot releases in a semi-field system (SFS) divided into six cages of 21 m2, each with five ovitraps. Five treatments were chosen to represent different points of a hypothetical invasion curve: 10%, 25%, 50%, 75%, and 90% of Wolbachia frequency. Collected eggs were counted and hatched, and the individuals from a net sample of 27% of larvae per treatment were screened for Wolbachia presence by RT-qPCR. Ovitrap positioning had no effect on egg hatching rate. Treatment strongly affected the number of eggs collected and also the hatching rate, especially when Wolbachia was at a 10% frequency. A second observation was done during the release of Wolbachia in Rio under a population replacement approach when bacterium frequency was estimated using 30 BG-Sentinel traps and 45 ovitraps simultaneously. By individually screening 35% (N = 3904) of larvae collected by RT-qPCR, we were able to produce a similar invasion curve to the one observed when all adults were individually screened. If sampling is reduced to 20%, monitoring Wolbachia frequency with 45 ovitraps would be roughly half the cost of screening all adult mosquitoes captured by 30 BG-Sentinels. Our findings support the scale-up of Wolbachia releases, especially in areas with limited resources to afford massive trapping with BG-Sentinel traps.

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Resumo A dengue ocorre no Timor-Leste desde 2005, porém não existe um programa de monitoramento e controle do "Aedes aegypti". O objetivo deste estudo foi de avaliar a armadilha ovitrampa iscada com atraente natural como uma possível ferramenta para monitorar o vetor das arboviroses: Dengue (DENV), Chikungunya (CHIKV) e Zika (ZIKV). O estudo foi realizado na cidade de Dili, capital do Timor-Leste, entre as semanas epidemiológicas 32 (02/08) a 48 (02/12) de 2016. Foram instaladas 70 armadilhas Ovitrampa, em residências de 15 sucos (ruas), de quatro Postos Administrativos (bairros) da cidade. Para as analises dos dados utilizou-se os indicadores entomológicos: Índice de Positividade de Ovitrampa (IPO), Índice de Densidade Vetorial (IDV) e Índice de Densidade de Ovos (IDO). Durante o experimento foram coletados 158.904 ovos de Aedes spp.. O IPO demonstrou que todas as áreas tiveram 98% a 100% de armadilhas contendo ovos de Aedes spp.. Os indicadores IDO e IPO apresentaram correlações positivas e significativa com a temperatura. A defasagem de duas e três semanas para precipitação indicou correlação positiva significativa para IDV e IDO. Portanto, a armadilha ovitrampa é uma ferramenta que pode integrar as ações de um programa de monitoramento e controle de Aedes spp. no Timor-Leste.

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Abstract INTRODUCTION: Areas at risk of transmission of arboviruses have been monitored using ovitraps. This study aimed to evaluate the spatial distribution of Aedes aegypti in vulnerable areas for the transmission of arboviruses and assess the influence of climatic conditions on the infestation of these culicids. METHODS: Ovitraps were installed in Agrestina, Pernambuco, Northeastern Brazil. RESULTS: Overall, 44,936 eggs were collected, and the indexes of infestation varied. Relative humidity was significantly associated with the infestations. CONCLUSIONS: Using ovitraps, entomologic indexes and analysis of climatic factors might be good strategies for monitoring vulnerable areas for the transmission of arboviruses.

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OBJECTIVES: To analyze the relationship between the occurrence of dengue and ovitrap positivity and dengue egg density in two Amazonas municipalities (Brazil) in 2016. METHODS: We performed a case-control study using secondary data from the dengue fever surveillance system. Ovitraps distributed regularly in the urban area of two cities were used to monitor the presence of the vector. The relationship between egg positivity, egg density and the location of dengue cases was evaluated using two approaches as follows: (i) based on the result of the nearest neighbour ovitrap and (ii) based on the results of the set of ovitraps within the influence area of 300 m from the location of each case and control. RESULTS: During the study period, 229 confirmed cases of dengue fever were reported in Tabatinga and 89 cases in Itacoatiara. In this study, we found that the positivity of ovitraps was related to the occurrence of dengue in Tabatinga and Itacoatiara. An association between egg density of Ae. aegypti and dengue occurrence was also observed in Itacoatiara. The temporal lags for ovitrap positivity measurements were predominantly 15 or 30 days. A dengue association for egg density for a 15-day time lag was detected for one of the case-control approaches. CONCLUSIONS: The location of dengue cases is related to ovitrap egg positivity, while a less evident possible association may exist for egg density. This indicates that these traps could be used to improve vector control actions.

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OBJECTIVE: To analyze the association of dengue fever incidence with Aedes mosquito's abundance, and the effect of climatological and geographical variables, in a region in Morelos State, Mexico. MATERIALS AND METHODS: Weekly data during the period 2010 to 2014 was used. Mosquito abundance was determined using ovitraps. Confirmed dengue cases were obtained from the Epidemiological Surveillance System. Climatic variables were obtained from weather monitoringstations. The correlation between climate variables and ovitraps data was estimated using a multivariate regression model. RESULTS: A correlation of mosquito abundance with dengue fever incidence, and a yearly pattern with seasonal variations were observed. The daily mean temperature, relative humidity and rainfall parameters were associated with mosquito egg abundance. Time lags of three and four weeks between egg counts and dengue fever incidence were observed. CONCLUSION: Time lags between egg counts and dengue incidence could be useful for prevention and control interventions.

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Abstract: Objective: To analyze the association of dengue fever incidence with Aedes mosquito's abundance, and the effect of climatological and geographical variables, in a region in Morelos State, Mexico. Materials and methods: Weekly data during the period 2010 to 2014 was used. Mosquito abundance was determined using ovitraps. Confirmed dengue cases were obtained from the Epidemiological Surveillance System. Climatic variables were obtained from weather monitoring stations. The correlation between climate variables and ovitraps data was estimated using a multivariate regression model. Results: A correlation of mosquito abundance with dengue fever incidence, and a yearly pattern with seasonal variations were observed. The daily mean temperature, relative humidity and rainfall parameters were associated with mosquito egg abundance. Time lags of three and four weeks between egg counts and dengue fever incidence were observed. Conclusion: Time lags between egg counts and dengue incidence could be useful for prevention and control interventions.

Resumen: Objetivo: Analizar la asociación de la incidencia de dengue con la abundancia de mosquitos Aedes y el efecto de variables climatológicas, en una región de Morelos, México. Material y métodos: Se utilizaron datos semanales durante el 2010-2014. La abundancia de mosquitos se determinó utilizando ovitraps. Los casos de dengue se obtuvieron del Sistema de Vigilancia Epidemiológica. Las variables climáticas se obtuvieron de estaciones climatológicas locales. La correlación entre las variables climáticas y los datos de ovitrampas se estimó mediante un modelo de regresión multivariado. Resultados: Se observó una correlación de la abundancia de mosquitos con la incidencia de dengue. La temperatura media diaria, humedad relativa y la precipitación pluvial se asociaron con abundancia de mosquitos. Se observó un desfase temporal de tres a cuatro semanas entre cuentas de huevos y la incidencia de dengue. Conclusión: Los intervalos entre las cuentas de huevos y la incidencia de dengue podrían ser utilizados para planear intervenciones de prevención y control.

Assuntos