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The increasing growth of the automobile industry and the need of overusing personal vehicles amplifies problems directly related to road safety, such as the degradation of the quality of the roads, the increase in volume of the automobile flow, and through the addition of dangerous weather events caused by climate change. To alleviate these emerging problems, intelligent cooperative communication systems (C-ITS) and Internet of Things (IoT) solutions emerge, allowing the overcome of human and local sensory systems limitations through the collection and distribution of relevant data in connected vehicles, which is fundamental in finding solutions that transform the concept of Smart Cities into reality. This dissertation implements an intra- and inter-vehicle sensory data collection system, starting with the acquisition of relevant data present on the CAN bus, collected through the vehicle’s OBD-II port and external sensors. Use is made of short-range communications such as Bluetooth-Low-Energy (BLE), Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) in conjunction with long-range cellular communications (LTE/5G). Data access endpoints are provided through an API and a MQTT broker. At last, logging methods are developed to allow conscious debugging of these systems, as well as to evaluate timing restrictions. The results of the experimental tests carried out reveal the usefulness of the acquired data, which allows the realization of detailed longitudinal analyzes of dangerous roads, as well as notifying, in near real-time, adverse road conditions to drivers. Therefore, the data collection system developed reveals itself as a potentially valuable tool for providing useful information both to competent authorities and to the common population, as a method to improve road safety. O constante crescimento da indústria automóvel e a necessidade do sobreuso do veículo pessoal amplificam problemas diretamente relacionados com a segurança rodoviária, tais como a degradação da qualidade das estradas, o aumento do volume de fluxo automóvel e o acréscimo de eventos metereológicos perigosos causados pelas alterações climáticas. Como forma de atenuar estes problemas emergentes, surgem os sistemas inteligentes de comunicação cooperativos (C-ITS) e de internet das coisas (IoT), que permitem ultrapassar limitações humanas e de sistemas sensoriais locais através da recolha e distribuição de dados em veículos conectados, algo fundamental para encontrar soluções que transformem o conceito de Smart City em realidade. A presente dissertação implementa um sistema de recolha de dados sensoriais intra- e inter-veículares, começando pela aquisição de dados relavantes presentes no barramento CAN, coletados através da porta OBD-II do veículo e de sensores externos. É feito uso de comunicações de curto alcance tais como Bluetooth-Low-Energy (BLE), Veículo-a-Veículo (V2V), e Veículo-a-Infrastrutura (V2I) em conjunto com comunicações celulares de longo alcance (LTE/5G). São fornecido endpoints de acesso aos dados através duma API e de um broker MQTT. Por fim métodos de logging são desenvolvidos para permitir depuração consciente destes sistemas e avalição de requisitos temporais. Os resultados dos testes experimentais efetuados revelam a utilidade forte que os dados adquiridos contém, por permitirem a realização de análises longitudinais detalhadas a estradas de perigo, assim como para fornecimento, em quase tempo-real, de condições adversas da estrada a condutores. Deste modo, o sistema de recolha de dados desenvolvido revela-se como ferramenta potencialmente valiosa para o fornecimento de informação útil tanto a autoridades competentes como à população comum, como meio de melhoria da segurança rodoviária. Mestrado em Engenharia de Computadores e Telemática

Chikungunya virus (CHIKV) is a re-emerging disease caused by an alphavirus of the Togaviridae family. Since its first description in 1952, the disease has spread worldwide, affecting populations in both tropical and temperate countries. To date, there is no licensed vaccine or specific pharmacological treatment. Therefore, there is an increasing urgency in developing new antiviral drugs capable of specifically inhibiting viral replication. In the present work, we report the synthesis and antiviral activity evaluation of nineteen naphthoquinone derivatives, containing a sulfonamide or sulfonate group. Cell viability assays indicated a low toxic potential for all tested compounds and inhibitory assays against CHIKV identified five compounds with potent activity. The compounds were also evaluated for their virucidal potential, and the results demonstrated that compound 11a exhibited a virucidal effect higher than 70% in the treatment with 20 µM. Furthermore, in silico studies were performed to predict the antiviral drug targets.

Background Aedes aegypti, the main arboviral mosquito vector, is attracted to human dwellings and makes use of human-generated breeding sites. Past research has shown that bacterial communities associated with such sites undergo compositional shifts as larvae develop and that exposure to different bacteria during larval stages can have an impact on mosquito development and life-history traits. Based on these facts, we hypothesized that female Ae. aegypti shape the bacteria communities of breeding sites during oviposition as a form of niche construction to favor offspring fitness. Results To test this hypothesis, we first verified that gravid females can act as mechanical vectors of bacteria. We then elaborated an experimental scheme to test the impact of oviposition on breeding site microbiota. Five different groups of experimental breeding sites were set up with a sterile aqueous solution of larval food, and subsequently exposed to (1) the environment alone, (2) surface-sterilized eggs, (3) unsterilized eggs, (4) a non-egg laying female, or (5) oviposition by a gravid female. The microbiota of these differently treated sites was assessed by amplicon-oriented DNA sequencing once the larvae from the sites with eggs had completed development and formed pupae. Microbial ecology analyses revealed significant differences between the five treatments in terms of diversity. In particular, between-treatment shifts in abundance profiles were detected, showing that females induce a significant decrease in microbial alpha diversity through oviposition. In addition, indicator species analysis pinpointed bacterial taxa with significant predicting values and fidelity coefficients for the samples in which single females laid eggs. Furthermore, we provide evidence regarding how one of these indicator taxa, Elizabethkingia, exerts a positive effect on the development and fitness of mosquito larvae. Conclusions Ovipositing females impact the composition of the microbial community associated with a breeding site, promoting certain bacterial taxa over those prevailing in the environment. Among these bacteria, we found known mosquito symbionts and showed that they can improve offspring fitness if present in the water where eggs are laid. We deem this oviposition-mediated bacterial community shaping as a form of niche construction initiated by the gravid female.

The ‘2019 Research Capacity Network (REDe) workshop series’ was an initiative led by Brazil-based REDe coordinators and The Global Health Network (TGHN) in partnership with Brazilian researchers interested in arboviruses. This workshop initiative has provided crucial training to the local research community offering transferable skills to effectively respond to health emergencies, with an impact beyond arboviral diseases, as evidenced by further activities undertaken during the COVID-19 pandemic. The success of this approach resulted from several factors, especially the workshops’ local leadership and the combination of in-person training with online sharing of the resources generated in the local language. Analytics data from REDe online platform evidenced the wider reach of the shared resources to a larger audience than the workshop attendees. Importantly, the impact of this approach extends beyond the workshop series per se, with workshop participants afforded access to wider training, career development and collaborative opportunities through REDe and TGHN platforms. In addition, this initiative design resulted in the development of new collaborations between the workshop leaders and other local researchers, who have been jointly writing research projects and applying for grants. As a result, REDe has become a highly dynamic community of practice for health researchers in the region, strengthening the research culture and improving connectivity. Here, we describe the design and implementation of this initiative and demonstrate the value of integrating local expertise, and a practical workshop series format with digital dissemination of research resources and training materials to generate a vibrant and robust community of practice.

Background Botanical substances such as essential oils (EOs) have demonstrated insecticidal properties and are a valid option for vector control. However, free EOs are unreliable as mosquito larvicides due their easy degradation by environmental exposure to ultraviolet light and higher temperatures. Here, we assessed the efficacy of a mosquito larvicide based on orange oil in a yeast-based delivery system against Aedes aegypti strains with different resistance status towards chemical neurotoxic insecticides. This larvicide preparation was physicochemically characterized in a previous report. Methods Larvae of four Ae. aegypti strains from different regions of Brazil and different resistance profiles for deltamethrin (pyrethroid) and temephos (organophosphate) were tested against yeast-encapsulated orange oil (YEOO) in laboratory conditions for measurement of LC50 and LC90 values. The same assays were performed with the Belo Horizonte strain under environmental conditions (natural light and temperature). The resistance profiles of these strains were compared to the Rockefeller reference strain in all conditions. Results YEOO was found to be a highly active larvicide (LC50 Ae. aegypti strains tested in both laboratory conditions (LC50 = 8.1–24.7 mg/L) and environmental conditions with natural light and temperature fluctuation (LC50 = 20.0–49.9 mg/L). Moreover, all strains were considered susceptible (RR 90–95 of Belo Horizonte in the laboratory, probably due the higher heterogeneity associated with older egg papers (> 5 months). Conclusion YEOO demonstrates high larvicidal activity against Ae. aegypti strains with resistant phenotypes for deltamethrin (PY) and temephos (OP). This larvicidal activity suggests the potential for the development of YEOO as an alternative intervention to synthetic insecticides in integrated vector management programs, for populations with resistance to commonly used insecticides. Graphical Abstract

With 40 million people and substantial county and regional variation in socio-demographics and health services, California is an important setting to study disparities. Its population -- 39.1% Latino, 5.3% Black, and 14.4% Asian -- experienced 54,124 COVID-19 deaths through March 7, 2021, the highest nationally. We analyzed California’s racial/ethnic disparities in COVID-19 exposure risks, testing rates, test positivity, and case rates, through October 2020. We combined data from 15.4 million SARS-CoV-2 tests with sub-county exposure risk estimates from the American Community Survey. Based on accumulated evidence, we defined “high exposure risk” households as those with ≥1 essential workers and fewer rooms than inhabitants. Latino individuals are 8.1 times more likely to live in high exposure risk households than White individuals (23.6% vs. 2.9%); overrepresented in cumulative cases (3,784 vs. 1,112 per 100,000); and underrepresented in cumulative testing (35,635 vs. 48,930 per 100,000). These risks and outcomes were worse for Latinos than for other racial/ethnic groups. Sub-county disparity analyses can inform local targeting of interventions and resources, including community-based testing and vaccine access and uptake measures. Tracking COVID-19 disparities and developing equity-focused public health programming that mitigates effects of systemic racism can help improve health outcomes among California’s populations of color.

Deployment of Wolbachia to mitigate dengue (DENV), Zika (ZIKV) and chikungunya (CHIKV) transmission is ongoing in 12 countries. One way to assess the efficacy of Wolbachia releases is to determine invasion rates within the wild population of Aedes aegypti following their release. Herein we evaluated the accuracy, sensitivity and specificity of the Near Infrared Spectroscopy (NIRS) in estimating the time post death, ZIKV-, CHIKV-, and Wolbachia-infection in trapped dead female Ae. aegypti mosquitoes over a period of 7 days. Regardless of the infection type, time post-death of mosquitoes was accurately predicted into four categories (fresh, 1 day old, 2–4 days old and 5–7 days old). Overall accuracies of 93.2, 97 and 90.3% were observed when NIRS was used to detect ZIKV, CHIKV and Wolbachia in dead Ae. aegypti female mosquitoes indicating NIRS could be potentially applied as a rapid and cost-effective arbovirus surveillance tool. However, field data is required to demonstrate the full capacity of NIRS for detecting these infections under field conditions., Santos et al. demonstrate that the Near Infrared Spectroscopy (NIRS) can accurately estimate the death time of trapped female Aedes aegypti and vector infection with Zika virus, Chikungunya virus, or Wolbachia in a 7-day trapping period. This study suggests that NIRS may provide an accurate and inexpensive tool that improves arbovirus surveillance systems.

Aedes aegypti is adapted to live in close association with human dwellings, where it lays eggs in several man-made container types with a broad range of size, shape, and material. Biotic and abiotic conditions of larval habitats determine the abundance and body size of emerging adult mosquitoes. Here, we estimated the predictive potential of physicochemical water variables for Culicidae immature abundance and Ae. aegypti adult body size in four neighborhoods with distinct urban landscapes in Rio de Janeiro, Brazil. Domestic water holding containers (N = 240) were inspected for the presence of Culicidae immatures and had several physiochemical parameters measured. Larvae and pupae were counted, and pupae were reared to the adult stage for taxonomic identification. Dry weight and wing size were measured for Ae. aegypti adult mosquitoes (N = 981). The association between larval habitat parameters with Culicidae abundance and Ae. aegypti body size data was estimated through linear mixed models and generalized linear mixed models, respectively, with the neighborhood as random effect. The abundance of immature Culicidae in larval habitats (from which >90% of adults emerging from field collected pupae were Ae. aegypti) was positively associated with container volume and the dissolved organic carbon concentration (DOC). Female average dry weight and male and female wing lengths were positively associated with larval habitat temperature whereas male average dry weight was positively related to water conductivity. Aedes aegypti originating from larval habitats with Ae. albopictus exhibited no differences in median wing length and dry body weight when compared with specimens collected in containers exclusively colonized by Ae. aegypti. These results demonstrate that container water volume (characteristic easily observed in the field) and DOC (often higher in unmanaged water holding recipients) is related to higher Ae. aegypti immature density. Estimating the effects of physicochemical water variables on immature abundance and adult body size can provide valuable information for predicting arbovirus transmission risk in endemic settings. Funding Agencies|US National Institutes of Health Fogarty International Center FIRCA [R03TW00744601A1]; Conselho Nacional de Desenvolvimento Cientifico e TecnologicoNational Council for Scientific and Technological Development (CNPq) [12446/2018]; Preventing and Combating the Zika Virus MCTIC/FNDCT-CNPq/MEC-CAPES/MS-Decit. [440929/2016-4]; Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro [E-26/203.064/2016, E-26/201.335/2016]; Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-CAPESCAPES [001]; Coordination for the Improvement of Higher Education Personnel-CAPESCAPES; Fiocruz (Programa Institucional de Internacionalizacao da Fiocruz PrInt FiocruzCAPES)

Despite worldwide efforts to understand the transmission dynamics of Zika virus (ZIKV), scanty evaluation has been made on the vector competence of Aedes aegypti fed directly on viremic human and non-human primates (NHPs). We blood-fed Ae. aegypti from two districts in Rio de Janeiro on six ZIKV infected pregnant rhesus macaques at several time points, half of which were treated with Sofosbuvir (SOF). Mosquitoes were analyzed for vector competence after 3, 7 and 14 days of incubation. Although viremia extended up to eight days post monkey inoculation, only mosquitoes fed on the day of the peak of viremia, recorded on day two, became infected. The influence of SOF treatment could not be assessed because the drug was administered just after mosquito feeding on day two. The global infection, dissemination and transmission rates were quite low (4.09%, 1.91% and 0.54%, respectively), no mosquito was infected when viremia was below 1.26 &times, 105 RNA copies/mL. In conclusion, Ae. aegypti vector competence for ZIKV from macaques is low, likely to be due to low viral load and the short duration of ZIKV viremia in primates suitable for infecting susceptible mosquitoes. If ZIKV infection in human and macaques behaves similarly, transmission of the Zika virus in nature is most strongly affected by vector density.

A novel method for the synthesis of nonsymmetrical 3,3’-(aryl/alkyl-methylene)bis-2-hydroxy-1,4-naphthoquinones was developed by using the Mannich adduct of naphthoquinone and the reaction with another moiety of 2-hydroxy-1,4-naphthoquinone. This novel method produces for the first time nonsymmetrical 3,3’-(aryl/alkyl-methylene)bis-2-hydroxy-1,4-naphthoquinones. In a preliminary study, these compounds (15c, 15f and 15h) were evaluated regarding their effect over the viability of PC3 metastatic prostate cancer cell using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays at 100 µM. Three of these compounds presented relevant cytotoxic effects at 72 h posttreatment.

Background Effective mosquito control approaches incorporate both adult and larval stages. For the latter, physical, biological, and chemical control have been used with varying results. Successful control of larvae has been demonstrated using larvicides including insect growth regulators, e.g. the organophosphate temephos, as well as various entomopathogenic microbial species. However, a variety of health and environmental issues are associated with some of these. Laboratory trials of essential oils (EO) have established the larvicidal activity of these substances, but there are currently no commercially available EO-based larvicides. Here we report on the development of a new approach to mosquito larval control using a novel, yeast-based delivery system for EO. Methods Food-grade orange oil (OO) was encapsulated into yeast cells following an established protocol. To prevent environmental contamination, a proprietary washing strategy was developed to remove excess EO that is adsorbed to the cell exterior during the encapsulation process. The OO-loaded yeast particles were then characterized for OO loading, and tested for efficacy against Aedes aegypti larvae. Results The composition of encapsulated OO extracted from the yeast microparticles was demonstrated not to differ from that of un-encapsulated EO when analyzed by high performance liquid chromatography. After lyophilization, the oil in the larvicide comprised 26–30 percentage weight (wt%), and is consistent with the 60–65% reduction in weight observed after the drying process. Quantitative bioassays carried with Liverpool and Rockefeller Ae. aegypti strains in three different laboratories presented LD50 of 5.1 (95% CI: 4.6–5.6) to 27.6 (95% CI: 26.4–28.8) mg/l, for L1 and L3/L4 mosquito larvae, respectively. LD90 ranged between 18.9 (95% CI: 16.4–21.7) mg/l (L1 larvae) to 76.7 (95% CI: 69.7–84.3) mg/l (L3/L4 larvae). Conclusions The larvicide based on OO encapsulated in yeast was shown to be highly active (LD50 Ae. aegypti. These results demonstrate its potential for incorporation in an integrated approach to larval source management of Ae. aegypti. This novel approach can enable development of affordable control strategies that may have significant impact on global health.

Este documento muestra el papel que representa para la comunidad indígena Nasa la emisora de interés público1 USWAL NASA YUWE STEREO, dentro del espacio territorial de Caldono, al nororiente del Cauca. De esta manera, el foco de estudio se fundamenta en su funcionamiento y la influencia que ejerce en la gente de Caldono, una emisora creada por la comunidad Nasa dentro de un escenario de postconflicto, de igual manera da cuenta del reconocimiento que ha logrado en una zona de reconciliación, a pesar de la ausencia del estado y autoridades públicas. El trabajo que se presenta es el resultado de un ejercicio de inmersión que explica el funcionamiento de un medio de comunicación construido y liderado por los indígenas Nasa; de igual manera visibiliza la articulación de las herramientas comunicativas utilizadas, que propician un espacio de reunión y armonización dentro de un colectivo que históricamente ha sido olvidado por el Estado colombiano y paralelamente, ha sufrido ataques por grupos al margen de la ley. Por lo tanto, el presente documento quiere mostrar el papel que juega la emisora Uswal Nasa Yuwe Stereo como agente de encuentro, participación y cambio social entre los habitantes de Caldono, Cauca. This document shows the role of the public interest broadcaster for the Nasa indigenous community1 USWAL NASA YUWE STEREO, within the territorial space of Caldono, in the northeast of Cauca. In this way, the focus of study is based on its operation and the influence that it exerts on the people of Caldono, a station created by the Nasa community within a post-conflict scenario, in the same way it gives an account of the recognition it has achieved in a zone of reconciliation, despite the absence of the state and public authorities. The work presented is the result of an immersion exercise that explains the operation of a media built and led by the Nasa Indians; In the same way, it makes visible the articulation of the communicative tools used, which provide a space for meeting and harmonization within a collective that has historically been forgotten by the Colombian State and, in parallel, has suffered attacks by groups outside the law. Therefore, this document wants to show the role played by the Uswal Nasa Yuwe Stereo radio station as a meeting, participation and social change agent among the inhabitants of Caldono, Cauca. Comunicador Social http://unidadinvestigacion.usta.edu.co Pregrado

O presente estudo visa identificar que comportamentos de liderança que possam promover a eficácia do trabalho em equipa tendo como base a partilha do conhecimento entre os membros. Para o efeito o estudo centra-se numa lógica de modelos input-processes-output, em que as investigações empíricas têm-se revelado escassas. As hipóteses colocadas foram que a partilha do conhecimento entre membros aumenta a eficácia dos mesmos, a liderança é moderadora da relação entre a partilha do conhecimento e a eficácia da equipa. O estudo conta com uma amostra de 207 indivíduos totalizando 55 equipas da área de consultoria. Para medir as variáveis foram utilizadas escalas de Morgeson, DeRue & Karam (2010) para a liderança, Choi (2010) para a partilha do conhecimento e González-Romá et. al (2009) para a eficácia. Os resultados não forneceram suporte para todas as hipóteses avançadas, sendo assim necessário para um estudo futuro a alteração das variáveis propostas ou acréscimo de mais variáveis para resultados mais significativos. This study aims to identify leadership behaviors that can promote teamwork effectiveness based on knowledge sharing among members. To this end, the study focuses on a logic of input-processes-output models, in which empirical investigations have been scarce. The assumptions made were that knowledge sharing among members increases their effectiveness, leadership moderating the relationship between knowledge sharing and team effectiveness. The study has a sample of 207 individuals totaling 55 consulting teams. To measure the variables, we used scales from Morgeson, DeRue & Karam (2010) for leadership, Choi (2010) for knowledge sharing and González-Romá et. al (2009) for effectiveness. The results did not provide support for all advanced hypotheses, so it is necessary for future study to change the proposed variables or to add more variables to more significant results.

Background: Aedes albopictus, the Asian tiger mosquito, is an exotic invasive species in Europe. It has substantial public health relevance due to its potential role in transmitting several human pathogens. Out of the European coun‑ tries, Spain has one of the highest risk levels of autochthonous arbovirus transmission due to both the high density of Ae. albopictus and the extensive tourist infux from vector-endemic areas. This study aims to investigate the suscep‑ tibility of fve Ae. albopictus populations from mainland Spain and the Balearic Islands to a Brazilian Zika virus (ZIKV) strain. Methods: The F1 generation of each Ae. albopictus population was orally challenged with a ZIKV-infected blood meal (1.8×106 PFU/ml). At 7 and 14 days post-infection (dpi), mosquito bodies (thorax and abdomen) and heads were individually analysed through RT-qPCR to determine the infection rate (IR) and dissemination rate (DR), respectively. The saliva of infected mosquitoes was inoculated in Vero cells and the transmission rate was assessed by plaque assay or RT-qPCR on ~33 individuals per population. Results: The IR and DR ranged between 12–88%, and 0–60%, respectively, suggesting that ZIKV is capable of cross‑ ing the midgut barrier. Remarkably, no infectious viral particle was found in saliva samples, indicating a low ability of ZIKV to overcome the salivary gland barrier. A subsequent assay revealed that a second non-infective blood meal 48 h after ZIKV exposure did not infuence Ae. albopictus vector competence. Conclusions: The oral experimental ZIKV infections performed here indicate that Ae. albopictus from Spain become infected and disseminate the virus through the body but has a limited ability to transmit the Brazilian ZIKV strain through biting. Therefore, the results suggest a limited risk of autochthonous ZIKV transmission in Spain by Ae. albopictus info:eu-repo/semantics/publishedVersion

Mosquito midgut microbiota is a key component of vector competence, as gut bacteria can disturb pathogen development. In this study, we addressed the microbiota composition of Aedes aegypti during its lifespan, under field conditions. We also investigated the possible effects of environment, dietary regime and ageing on the gut community composition. We employed culture independent and dependent approaches to characterise vector microbiota. There was evidence of a lifelong stable core microbiota after mosquitoes were released into an urban settlement, where they presumably fed on a range of vertebrate hosts and carbohydrate sources. This core was formed mainly of bacteria belonging to the genera Pseudomonas, Acinetobacter, Aeromonas and Stenotrophomonas and to the families Oxalobacteraceae, Enterobacteriaceae and Comamonadaceae. We showed that both dietary regime and age were associated with the abundance of some bacterial groups in the Ae. aegypti microbiota. The majority of the bacterial groups we identified have been detected in the midgut of Ae. aegypti from laboratory and wild populations, indicating a possible core microbiota associated with this mosquito species. Our findings suggest that Ae. aegypti harbours a stable bacterial community during its adult life, similar to mosquito populations from distinct geographic areas, which may be further explored for arbovirus biocontrol strategies.

We report the first use of near-infrared spectroscopy for rapid, low-cost, noninvasive detection of Zika virus in Aedes aegypti., The accelerating global spread of arboviruses, such as Zika virus (ZIKV), highlights the need for more proactive mosquito surveillance. However, a major challenge during arbovirus outbreaks has been the lack of rapid and affordable tests for pathogen detection in mosquitoes. We show for the first time that near-infrared spectroscopy (NIRS) is a rapid, reagent-free, and cost-effective tool that can be used to noninvasively detect ZIKV in heads and thoraces of intact Aedes aegypti mosquitoes with prediction accuracies of 94.2 to 99.3% relative to quantitative reverse transcription polymerase chain reaction (RT-qPCR). NIRS involves simply shining a beam of light on a mosquito to collect a diagnostic spectrum. We estimated in this study that NIRS is 18 times faster and 110 times cheaper than RT-qPCR. We anticipate that NIRS will be expanded upon for identifying potential arbovirus hotspots to guide the spatial prioritization of vector control.

Background Chemical control is still a major strategy to constrain vector density and mitigate pathogen transmission. However, insecticide overuse poses a high selective pressure, favouring the spread of resistance alleles in natural populations. In an insecticide-free environment, a fitness cost is expected in resistant insects when compared to susceptible counterparts. This study investigates whether insecticide resistance to an organophosphate (temephos) and a pyrethroid (deltamethrin) is associated with fitness traits in four Aedes aegypti wild populations sampled every three months over one year. Findings We measured development time from larvae to adult, female survival, wing length, fecundity, and adult resistance to starvation in field insecticide resistant Ae. aegypti populations four times over a year. These results were confronted with resistance levels to temephos and deltamethrin and with potentially related mechanisms, including a kdr mutation in the pyrethroid target site. No differences in fitness cost were found after contrasting mosquitoes from the same population collected throughout a year, irrespective of differences in insecticide resistance levels. Additionally, significant differences were not observed among field populations. However, compared to the reference strain Rockefeller, field females survived significantly less. Moreover, larval development was equal or slower in three out of four field populations. In no case differences were evidenced in starvation tolerance, wing length, and fecundity. Conclusions Overall, field resistant mosquitoes seemed to have a slight fitness disadvantage when compared with the Rockefeller susceptible strain which might represent a potential fitness cost of insecticide resistance. However, after comparing Ae. aegypti from the same population but sampled at different moments, or from different field populations, mosquito life-history traits varied independently of resistance ratios. The metabolic deviations necessary to overcome the adverse effects of insecticides may cause an energy trade-off that affects energy allocation and ultimately basic demands of insect biology. The extent of fitness cost due to insecticide resistance is critical information to delay the evolution of resistance in wild vector populations.