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Dengue fever (DF) is one of the most rapidly spreading mosquito-borne viral diseases in the world. It can impose an enormous socioeconomic and disease burden on the world's population. The spatial and temporal distribution patterns of DF cases in China are heterogeneous. It is evident that further research is necessary to identify the high-risk areas of dengue occurrence and associated risk factors at a fine spatiotemporal scale. This will facilitate the prevention and control of DF transmission. With the rapid development of remote sensing (RS) and geographic information system (GIS) technology, RS and GIS technology have played an important role in monitoring, forecasting, and identifying influencing factors and formulating prevention and control strategies for DF. In China, the majority of dengue cases were clustered in Guangdong and Yunnan Provinces. In this study, Bayesian spatiotemporal models were fitted at the county level in order to quantify the relationships between environmental and socioeconomic factors and DF. Our findings indicate that both environmental and socioeconomic factors can affect the transmission of DF in Guangdong and Yunnan Provinces. However, the underlying drivers and the spatially clustered patterns observed in the two provinces appear to be different. The results indicate that elevated temperatures facilitate the transmission of DF, but it was found that the risk of DF begins to decrease when the temperature exceeds 27.6 oC in Guangdong Province. There was a positive correlation between temperature and the incidence of DF, although no statistical significance was found in Yunnan Province. In Guangdong Province, the amount of precipitation did not significantly affect the incidence of DF. In Yunnan Province, the relationship between precipitation and DF is nonlinear. As the amount of precipitation increases, the risk of DF epidemics increases. In addition, vegetation cover can significantly affect the DF transmission, but the nonlinear relationships between vegetation cover and DF are diverse and complex in these two provinces. The incidence of DF was found to be positively correlated with the level of urbanization at the county level. The findings may prove beneficial to the governments of both provinces in the development of targeted strategies for the control of DF outbreaks at the county level. [ABSTRACT FROM AUTHOR]

Background: The biological larvicide Bacillus thuringiensis subsp. israelensis (Bti) represents a safe and effective alternative to chemical insecticides for mosquito control. Efficient control of mosquitoes implicates continuous and extensive application of Bti. This massive use of Bti imposes strong selective pressure, but the complex mode of action of the numerous synergistic Bti endotoxins lower the risk of the emergence of resistance. Although resistance to Bti has not been identified at the population level in nature, some larvae can survive Bti exposure, suggesting tolerance mechanisms. Here we investigated whether Bti-tolerant Aedes albopictus larvae experience any fitness costs. We also studied how this tolerance affects different aspects of the phenotype of the emerging adults that could be relevant for arboviral transmission. Methods: We exposed Ae. albopictus larvae to lethal concentration of Bti and studied the fitness and gut microbiota of tolerant larvae and their adult counterparts. We further compared the transcript abundance of nine key immunity genes in the gut of Bti-tolerant larvae and their emerging adults versus those not exposed to Bti. Results: Our results showed that Bti exposure has multifaceted impacts on Ae. albopictus mosquitoes during both larval and adult stages. The carry-over effect of Bti exposure on tolerant larvae manifested in reduced adult emergence rate, shorter lifespan, and decreased fecundity. Bti also alters the gut microbiota of both larvae and adults. We observed higher microbial diversity in Bti-tolerant larvae and changes in the richness of core microbiota. Bti infection and the altered microbiota triggered immune responses in the larval and adult guts. Conclusions: The observed reduction in mosquito fitness and changes in the composition of the microbiota of adults emerging from tolerant larvae could negatively influence mosquito vectorial capacity. Understanding these impacts is crucial for evaluating the broader implications of Bti-based insecticides in mosquito control programs. [ABSTRACT FROM AUTHOR]

Background: Knowledge of the distribution and abundance of disease-causing mosquito vectors is fundamental for assessing the risk of disease circulation and introduction. Aedes caspius (Pallas, 1771) and Aedes vexans (Meigen, 1830) have been implicated, to different extents, in the circulation of several arthropod-borne viruses (arboviruses). These two mosquitoes are vectors of Tahyna virus in Europe and are considered potential vectors of Rift Valley fever virus, a virus not present but at risk of introduction on the continent. Methods: In this work, we analysed abundance data collected during West Nile virus (WNV) surveillance in northern Italy (Po Plain) via 292 CO2-baited traps to evaluate the distribution and density of these two non-target mosquitoes. We modelled the distribution and abundance of these two mosquito species in the surveyed area using two distinct spatial analysis approaches (geostatistical and machine learning), which yielded congruent results. Results: Both species are more abundant close to the Po River than elsewhere, but Ae. caspius is present in the eastern and western parts of the plain, linked with the occurrence of rice fields and wetlands, while Ae. vexans is observed in the middle area of the plain. Conclusions: Presence and abundance data at the municipality level were obtained and made available through this work. This work demonstrates the importance of maintaining and improving entomological surveillance programs with an adequate sampling effort. [ABSTRACT FROM AUTHOR]

The article "ArboItaly: Leveraging open data for enhanced arbovirus surveillance in Italy" published in Frontiers in Pharmacology discusses the significant impact of arboviruses, such as West Nile, chikungunya, and dengue, on public health globally. It highlights the factors contributing to the reemergence of these viruses, including climate change, urbanization, and globalization. The paper introduces ArboItaly, a centralized repository consolidating epidemiological data on arboviral diseases in Italy to facilitate surveillance and response efforts. It emphasizes the need for robust public data and genomic surveillance systems to monitor and prevent arboviral epidemics. The article also discusses the environmental and socioeconomic factors influencing the spread of arboviruses, the integrated approaches for arbovirus control, and advancements in arbovirus research and vaccine development. The authors call for enhanced understanding of climate change's impact on arbovirus transmission, improved surveillance platforms, and international cooperation to address the evolving threat of arboviruses. [Extracted from the article]

Personal protection from mosquito bites is essential for preventing mosquito‐borne diseases. Mosquito repellents are effective methods for preventing mosquito bites. Due to their ease of use and indirect skin contact, mosquito‐repellent stickers loaded with essential oils (EOs) have recently become favoured as novel spatial repellents. To discover active EOs with high spatial repellency, 64 commercial EOs were screened using a modified arm‐in‐cage assay. Four EOs, including nutmeg, melissa, eucalyptus and cinnamon, displayed longer complete protection times (CPTs) of about 60 min. Ten main constituents from the four active EOs were identified by gas chromatography–mass spectrometry (GC–MS), and their spatial repellent activities were further evaluated. 1,8‐Cineole, cinnamaldehyde and citral showed potent repellent activity, with average CPTs of 67.5, 63.8 and 60 min respectively. The interactions of 1,8‐cineole and citral with odorant‐binding protein‐3 (OBP‐3) were studied via molecular docking. Both compounds are docked well in the high hydrophobic pocket and interacted with AealOBP3 through Van der Waals interactions with Phe105, Phe112, Leu114, Met48 and Val50. These natural products provide promising lead fragments for the further development of botanical spatial repellents. [ABSTRACT FROM AUTHOR]

This study investigates the efficacy of three different olfactory cues - cyclohexanone, linalool oxide (LO), and 6-methyl-5-heptan-2-one (sulcatone) - in attracting Aedes aegypti, the primary vector of dengue, using BG sentinel traps in a dengue-endemic area (urban Ukunda) in coastal Kenya. Two experiments were conducted. Experiment 1 compared solid formulations of the compounds in polymer beads against liquid formulations with hexane as the solvent. CO2-baited traps served as controls. In Experiment 2, traps were baited with each compound in the polymer beads, commercial BG-Lure, and CO2. Our results indicate that CO2-baited traps recorded the greatest Ae. aegypti captures in both Experiment 1 and 2, whereas trap captures with polymer beads and solvent-based treatments were comparable. In experiment 2, polymer bead-based treatments yielded significantly greater female captures, each recording ~ 2-fold more captures than traps baited with the BG-Lure. There was no significant difference, however, between the treatments. Female Ae. aegypti captured in CO2-baited traps were mainly unfed (91%), with fewer gravid mosquitoes (6.4%) compared to traps with test compounds (range; 12.7–21.1%). Male captures were lower in LO and BG-Lure baited traps compared to other treatments. Gravimetric analysis showed LO had a slower release rate compared to other compounds. The findings suggest that host-associated compounds loaded on polymer beads are more effective in trapping Ae. aegypti than commercial BG-Lure and reveal sex-specific differences in mosquito responses. These results have implications for mosquito surveillance and control programs, highlighting the potential for selective trapping strategies. [ABSTRACT FROM AUTHOR]

Mosquito‐borne diseases contribute substantially to the global burden of disease, and are strongly influenced by environmental conditions. Ongoing and rapid environmental change necessitates improved understanding of the response of mosquito‐borne diseases to environmental factors like temperature, and novel approaches to mapping and monitoring risk. Recent development of trait‐based mechanistic models has improved understanding of the temperature dependence of transmission, but model predictions remain challenging to validate in the field. Using West Nile virus (WNV) as a case study, we illustrate the use of a novel remote sensing‐based approach to mapping temperature‐dependent mosquito and viral traits at high spatial resolution and across the diurnal cycle. We validate the approach using mosquito and WNV surveillance data controlling for other key factors in the ecology of WNV, finding strong agreement between temperature‐dependent traits and field‐based metrics of risk. Moreover, we find that WNV infection rate in mosquitos exhibits a unimodal relationship with temperature, peaking at ~24.6–25.2°C, in the middle of the 95% credible interval of optimal temperature for transmission of WNV predicted by trait‐based mechanistic models. This study represents one of the highest resolution validations of trait‐based model predictions, and illustrates the utility of a novel remote sensing approach to predicting mosquito‐borne disease risk. [ABSTRACT FROM AUTHOR]

Background: Malaria is a global disease caused by the transmission of the malaria parasite through the bites of infected Anopheles mosquitoes. There are 4 kinds of common malaria parasites, among which oval malaria is mainly prevalent in tropical West Africa, with a narrow distribution range, mainly imported cases in China, which is relatively rare. Because the morphology, attack cycle, recrudescence and relapse are similar to those of Plasmodium vivax and, therefore, is easily missed and misdiagnosed. Methods: Malaria parasite-specific antigens were detected in whole blood samples using rapid diagnostic tests (RDT). Peripheral blood was used to prepare thick and thin smears, which were then stained with Giemsa for the identification of malaria parasites and different parasite morphologies under an oil microscope. Plasmodium species were identified using fluorescence quantitative PCR. Results: The patient's RDT revealed two red response lines (only T2 positive), indicating a single or mixed infection of three types of malaria (Plasmodium vivax, Plasmodium malarie, Plasmodium ovale) excluding Plasmodium falciparum. Thick smears exhibited various stages of Plasmodium such as hypertrophic rings and gametocytes, while thin films displayed Plasmodium trophozoites, gametocytes, etc., resembling oval malaria. The patients were diagnosed with Plasmodium ovum infection through fluorescence quantitative PCR, and targeted treatment was administered. Conclusions: The incidence of Plasmodium ovum infection is low, and there is a risk of overlooking or misdiagnosing the infection in laboratory tests. It is essential for laboratory staff to enhance their morphological recognition skills for Plasmodium and to integrate blood routine analysis, RDT, and PCR results in order to facilitate early diagnosis and prompt treatment. [ABSTRACT FROM AUTHOR]

BACKGROUND: Controlling the spread of arboviral diseases remains a considerable challenge due to the rapid development of insecticide resistance in Aedes mosquitoes. This study evaluated the effects of boric acid‐containing toxic sugar bait (TSB) on field populations of resistant Aedes aegypti mosquitoes. In addition, this study examined the flight activity and wing beat frequency and amplitude of males and the flight activity, fecundity, and insemination of females after pairing with males exposed to TSB. The population dynamics of Aedes mosquitoes under imbalanced sex ratios were examined to simulate realistic field conditions for male suppression under the effect of TSB. RESULTS: The mortality of male mosquitoes was consistently high within 24 h after exposure. By contrast, the mortality of female mosquitoes was inconsistent, with over 70% mortality observed at 168 h. The flight activity and wing beat amplitude of treated males were significantly lower than those of controls, but no significant difference in wing beat frequency was detected. The fecundity and insemination of treated female mosquitoes were lower than those of controls. A simulation study indicated that considerably low male population densities led to mating failures, triggering a mate‐finding Allee effect and resulting in persistently low population levels. CONCLUSION: Boric acid‐containing TSB could effectively complement current chemical intervention approaches to control resistant mosquito populations. TSB is effective in reducing field male populations and impairing male flight activity and female‐seeking behavior, resulting in decreased fecundity and insemination. Male suppression due to TSB potentially results in a small mosquito population. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

An important defense against the deadly diseases that mosquitoes transmit is the application of insecticides that reduce mosquito populations. Unfortunately, the evolution and subsequent spread of insecticide resistance has decreased their efficacy. Therefore, new mosquito control strategies are needed. One class of larvicides, known as photosensitive insecticides, or PSIs, kills larvae via light-activated oxidative damage. PSIs are promising larvicides because of their high larvicidal efficacy, rapid photodegradation, inexpensive cost, and mechanism that is dissimilar to other insecticide classes. We explored a novel delivery strategy for increasing both the larvicidal efficiency and environmental biocompatibility of PSIs, known as yeast encapsulation. Using the PSIs, curcumin and methylene blue, we measured the survival of Anopheles gambiae larvae and Escherichia coli following exposure to either non-encapsulated or yeast-encapsulated PSIs and a photoperiod. Yeast encapsulation increased the phototoxicity of both curcumin and methylene blue against mosquito larvae, likely by increasing ingestion. Furthermore, yeast encapsulation protected E. coli from the phototoxicity of yeast-encapsulated curcumin, but not yeast-encapsulated methylene blue. Yeast encapsulation increases the larvicidal efficacy of a PSI while also increasing biocompatibility. Therefore, yeast encapsulation of PSIs is a promising insecticide delivery strategy for mosquito control. [ABSTRACT FROM AUTHOR]

How landscape composition and configuration impact the distribution of multi-vector and multi-host mosquito vector-borne disease systems, such as West Nile virus (WNV), remains challenging because of complex habitat and resource requirements by hosts and vectors that affect transmission opportunities. We examined correlations between landscape composition and configuration and 2018 WNV sentinel chicken seroconversion in Florida, USA across the state and within five National Oceanic Atmospheric Administration (NOAA) bioclimatic regions to understand strength and variation of landscape effects during an elevated transmission year. Although few landscape studies have examined WNV in Florida, we expected higher percentages of residential or medium-developed landscapes and more fragmented landscapes would be positively correlated with WNV seroconversion owing to the main mosquito vector habitats and avian host distributions. However, we expected to find variation in the importance of forest, wetland, and agriculture landscapes across bioclimatic regions in the state. WNV seroconversion rates were calculated using Florida 2018 Department of Health WNV sentinel chicken seroconversion data from 187 flocks maintained by mosquito control programs. Percent land cover and edge density metrics were calculated for multiple land cover classes and within multiple buffer distances from chicken coops using 2019 National Land Cover Data. We used binomial generalized linear mixed effects models to calculate the importance of landscape metrics to WNV seroconversion. We found no statewide predictors of seroconversion, but as expected, the importance of landscape varied across regions. In the north-central part of the state, we found higher seroconversion in less populated suburban areas while higher seroconversion in south-central Florida was correlated with fragmented forested areas within 0.5 km of coops and intact woody wetland areas within 2 km of coops. This work corroborates previous findings that consistent landscape predictors of WNV are difficult to identify across broader geographic areas and sets the stage for additional work that incorporates climate and landscapes interactions for a greater understanding of WNV ecology in this geographic region. [ABSTRACT FROM AUTHOR]

Citizen science is recognized as an important tool to engage the public in important scientific and environmental issues that impact them. Mosquito surveillance-based citizen science in college curricula have not received much attention even though its usage has the potential to actively engage students in inquiry and elevate student support for science. FLAGG (Florida Aedes Genome Group) was a course-based internship where college students engaged in mosquito egg collections, learned about disease transmission, and gained an understanding of data collection in scientific research. This paper reports on a study comparing the outcomes of FLAGG participants with students in other college internships and students who had never done an internship. Findings show that participation in the citizen science mosquito control internship not only increased knowledge and skills in mosquito abatement, but also increased confidence and to a certain extent, sense of engagement, when compared to other groups. These results support the inclusion of citizen science methods in college-based curricula, where benefits extend beyond content learning. [ABSTRACT FROM AUTHOR]

Malaria parasites hijack the metabolism of their mammalian host during the blood-stage cycle. Anopheles mosquitoes depend on mammalian blood to lay eggs and to transmit malaria parasites. However, it remains understudied whether changes in host metabolism affect parasite transmission in mosquitoes. In this study, we discovered that Plasmodium infection significantly decreased the levels of the tryptophan metabolite, 5-hydroxytryptamine (5-HT), in both humans and mice. The reduction led to the decrease of 5-HT in mosquitoes. Oral supplementation of 5-HT to Anopheles stephensi enhanced its resistance to Plasmodium berghei infection by promoting the generation of mitochondrial reactive oxygen species. This effect was due to the accumulation of dysfunctional mitochondria caused by 5-HT-mediated inhibition of mitophagy. Elevating 5-HT levels in mouse serum significantly suppressed parasite infection in mosquitoes. In summary, our data highlight the critical role of metabolites in animal blood in determining the capacity of mosquitoes to control parasite infection. Author summary: Plasmodium infection causes symptoms ranging from fever, headache, convulsions to death that are associated with metabolic dysregulation in patients. Because Plasmodium is transmitted to mosquitoes through blood, it remains unclear how host metabolic changes affect parasite transmission in mosquitoes. In this study, we show that Plasmodium infection reduces the metabolite 5-HT in humans, mice and mosquitoes. Artificially increasing and decreasing 5-HT levels in mosquitoes inhibits and facilitates Plasmodium infection in mosquitoes, respectively. Mechanistic studies show that 5-HT inhibits mitophagy, leading to the accumulation of dysfunctional mitochondria, which exacerbates ROS generation. The increase in ROS, in turn, promotes parasite clearance. We also show that restoring the 5-HT levels in Plasmodium-infected mice to those of uninfected mice effectively suppresses parasite infection in mosquitoes. Collectively, these findings suggest the potential of correcting host metabolism to inhibit vector-borne parasite transmission. [ABSTRACT FROM AUTHOR]

This document contains three research reports. The first report examines the relationship between El Niño events and rainfall patterns in the eastern Bay of Bengal. The second report focuses on resolving the Mahadayi water dispute by analyzing rainfall data and estimating water discharge in the river basin. The third report explores the use of nanoparticle-based drug delivery systems to improve the treatment of malaria. The first article discusses the dysregulation of calcium ion signaling in pancreatic acinar cells and its implications for medical conditions. The second article investigates the metabolic reprogramming in immune cells during Mycobacterium tuberculosis infection. The third article explores the use of electric fields to repel mosquitoes and prevent mosquito-borne diseases. [Extracted from the article]

The spread of arboviruses like yellow fever, dengue, chikungunya, and Zika, transmitted by the invasive mosquito Aedes aegypti has led to the development of many strategies to suppress mosquito populations. Given the rapid development of resistance to common chemical larvicides and adulticides in some Ae. aegypti populations, as well as the ever-shrinking chemical options for mosquito control, there is a pressing need for new tools and deployment of those innovative tools as a component of integrative mosquito management programs. Prior to the adoption of any mosquito population intervention, be it conventional or innovative, understanding the baseline population is essential to evaluate the efficacy of the control measure. The Lee County Mosquito Control District in Florida has collected a three-year-long period of baseline entomological surveillance data collection for Ae. aegypti on Captiva and Sanibel Islands as foundational information prior to implementation of a new integrative mosquito management approach. We identified 18 mosquito species and described their population dynamics during the rainy and dry seasons. The two islands had no significant differences in species richness, diversity, dominance, or evenness overall. Yet, there were clear differences between the high rain season and low rain season in the Shannon diversity index, Simpson dominance index, and Pielou species evenness index within each site. Our data suggest that any innovative intervention should begin before mid to late April when the mosquito population is at its lowest and certainly before populations build up to their summer peak between June and September. These data also show the spatial distribution of Ae. aegypti is dynamic in space and time, identifying hotspots of mosquito abundance to focus on for future interventions. Overall, our study emphasizes the importance of entomological data collection to understand the population dynamics of Ae. aegypti mosquitoes, including the impact of environmental factors such as temperature and precipitation. [ABSTRACT FROM AUTHOR]

Background: In 2007, the first outbreak of Chikungunya in Italy generated great alarm, highlighting the health risks caused by exotic species recently introduced in Europe and the need to strengthen control actions against the vectors. Besides health risks, mosquitoes cause nuisance, and citizens are required to adopt control measures. While the economic aspects of mosquito control by public agencies have been investigated, the scientific literature on the costs of mosquito protection incurred by families is scarce. This study assessed the households' expenditure on protective measures against mosquitoes in Emilia-Romagna, a region in Northern Italy. Methodology/Principal findings: A phone questionnaire survey was conducted to collect data on the annual expenditure incurred by households for self-protection against mosquitos in relation to the perceived level of nuisance and the household and dwelling characteristics. Univariate and multivariate analyses were conducted to identify the main determinants influencing such expenditure, which resulted affected by dwelling characteristics, presence of children under 6 years of age, and health concerns of family members. The average annual household expenditure was estimated at 84.63 euros, about 30 times higher than the expenditure per household supported by regional and local administrations for interventions against mosquitoes in public areas, as calculated in a previous study. Conclusion/Significance: Household expenditure is mainly aimed at providing a direct defense against mosquito bites (mosquito nets, adulticides, skin-on repellents, etc.) while spending for more effective measures addressed to reduce mosquito density results marginal: e.g., only 3.5% of the total expenditure was dedicated to larval control. Control activities that lower the mosquito density in both private and public areas could reduce the use of household insecticides in urban environments and the related costs, and the risk of spread of imported arboviruses as well. Author summary: To achieve effectiveness, mosquito control requires the adoption of integrated pest management (IPM) methods and comprehensive strategies in both public and private areas. In the case of urban mosquitoes, the application of IPM in public areas alone may not reduce the insect population density to levels that limit the nuisance, particularly during daytime, and mitigate the risks of arbovirus outbreaks. In Italy, the control activities by local administrations are usually limited to public areas, while interventions in private areas are delegated to owners and residents. This study analyzed the expenses incurred by households to protect themselves from mosquitoes. We found that the average yearly cost per household was about € 84.63 (excluding the depreciation costs of mosquito nets, the average expenditure drops to € 58.63 per household), which was significantly higher than the average expenditure incurred by local administrations for their interventions in public areas (approximately € 3/household/year). The efficacy of domestic mosquito control methods is difficult to estimate due to the variety of strategies, tools and operating conditions. Moreover, the application of domestic tools is mainly driven by marketing instead of sound cost-effectiveness evaluations. [ABSTRACT FROM AUTHOR]

Background: Lymphatic filariasis (LF) is an infectious neglected tropical disease caused by mosquito-borne nematodes such as Wuchereria bancrofti, Brugia malayi, and Brugia timori. Globally, LF affects 51 million people, with approximately 863 million at risk in 47 countries. In Kenya, filariasis is endemic along the entire coastal strip, and more recently, at the Kenya–Ugandan border. The World Health Organization (WHO) recommends mass drug administration to reduce disease transmission and morbidity. Monitoring the effectiveness of such interventions relies on robust surveillance, achieved through microscopic examination of microfilariae in nighttime blood, detection of circulating filarial antigens (CFA), and molecular xenomonitoring. We focused on molecular xenomonitoring along the Kenyan coast due to its noninvasive nature and the opportunity to identify new vectors. Methods: In 2022, mosquitoes were collected from Kilifi, Kwale, and Taita-Taveta counties located within the LF endemic region in Kenya. Subsequently, genomic deoxyribonucleic acid (gDNA) was extracted from these mosquitoes for speciation and analysis of Wuchereria bancrofti infection rates. The impact of sociodemographic and household attributes on infection rates was assessed using generalized estimating equations. Results: A total of 18,121 mosquitoes belonging to Culicinae (63.0%, n = 11,414) and Anophelinae (37.0%, n = 6707) subfamilies were collected. Morphological identification revealed that Anopheline mosquitoes were dominated by An. funestus (45.4%, n = 3045) and An. gambiae (42.8%, n = 2873). Wuchereria bancrofti infection rates were highest in Kilifi (35.4%; 95% CI 28.0–43.3%, n = 57/161) and lowest in Taita Taveta (5.3%; 95% CI 3.3–8.0%, n = 22/412). The major vectors incriminated are An. rivulorum, An. funestus sensu stricto, and An. arabiensis. Mosquitoes of the An. funestus complex were significantly associated with LF transmission (OR 18.0; 95% CI 1.80–180; p = 0.014). Additionally, a higher risk of transmission was observed outdoors (OR 1.74; 95% CI 1.08–2.82; p = 0.024) and in homesteads that owned livestock (OR 2.00; 95% CI 1.09–3.66; p = 0.025). Conclusions: In this study, we identified An. funestus s.l. sibling species, An. rivulorum and An. funestus s.s., as the primary vectors of lymphatic filariasis along the Kenyan coast. These findings also highlight that a significant portion of disease transmission potentially occurs outdoors where indoor-based vector control tools, including long-lasting insecticidal nets and indoor residual spray, may not be effective. Therefore, control measures targeting outdoor resting mosquitoes such as zooprophylaxis, larval source management, and attractive sugar baits may have potential for LF transmission reduction. [ABSTRACT FROM AUTHOR]

Background: Aedes mosquito is the primary vector of emerging or re-emerging arboviruses that threaten public health worldwide. Many efforts have been made to develop interventions to control the Aedes mosquito. This scoping review was conducted to identify the nature and scope of educational interventions to prevent and control diseases transmitted through the Aedes mosquito. The findings can be used to evaluate, compare, and develop appropriate control strategies. Methods: The present scoping review was conducted in 2023 and used Arksey and O'Malley's approach, which involves five key stages. To search for academic papers, PubMed, Web of Science, Scopus and ScienceDirect databases were used with a combination of keywords about Aedes mosquitoes, educational interventions, and disease prevention and control. The search was not limited by the publication date, yet only included studies published in English. Studies were included that reported the educational interventions about Aedes mosquito control at the community or organizational level. The screening of papers was done based on the PRISMA-ScR guideline. Excel 2019 was used for data analysis. Results: Initially, 3,172 papers were extracted, and after screenings and reviews, a total number of 45 final papers were selected. The studies focused on educational interventions. Twenty interventional studies were at the organizational level and 25 at the community level. The latter was the most commonly used strategy. Interventions using educational approaches have achieved sustainable results. Out of the forty-five studies, twenty-one were assessed to have a low risk of bias. Conclusions: The present scoping review evaluates the effectiveness of educational interventions at various community levels for controlling Aedes-borne diseases, emphasizing the need for multidisciplinary collaboration. Controlling Aedes mosquitoes using education and attracting the community's participation is an effective approach to reduce diseases transmitted through Aedes. The development of education at different levels of the community, such as educational and occupational environments, can play a role in the effectiveness of societal education and can be more cost-effective. Maintaining the effect of this approach is challenging because it requires multi-sector and multidisciplinary team participation and active community engagement over the long term. Further research is required to explore the removal of barriers to the implementation of educational interventions and the consistency of effects. [ABSTRACT FROM AUTHOR]

Background and Aim: Efficient mosquito vectors are required to persist and propagate arthropod-borne diseases that seriously affect impoverished populations worldwide. Mosquito sensilla plays a crucial role in host-seeking and disease transmission to humans. This study aimed to distinguish between the several types of sensilla found on the antennae and maxillary palps of Culex pipiens and Aedes aegypti, matching this diversity with host preference and disease transmission. Methods: Overall, 1300 mosquitoes were collected and examined using dissection and light microscopy. Scanning electron microscopy was used to identify and describe the diverse types of sensilla found on the antennae and maxillary palps of C. pipiens and A. aegypti. Results: In total, 900 C. pipiens and 400 A. aegypti mosquitoes were identified. The antennae and maxillary palps of C. pipiens and A. aegypti carry both sensilla trichoidea and sensilla chaetica. The C. pipiens antenna has long and short grooved peg sensilla, whereas A. aegypti lacks long pegs and expresses only occasional short pegs. The maxillary palps express Capitate pegs in both mosquito species and exclusively show sensilla campaniform in A. aegypti. Conclusion: The lack of long-grooved pegs and the presence of few short pegs, along with campaniform sensilla, limit the host range of A. aegypti and reduce its susceptibility to many infections, unlike C. pipiens. [ABSTRACT FROM AUTHOR]

Chemical insecticides (organophosphates and pyrethroids) in the form of IRS (Indoor Residual Sprays) and LLINs (Long Lasting Insecticidal Nets) are the cornerstone for vector control, globally. However, their incessant use has resulted in widespread development of resistance in mosquito vectors, warranting continuous monitoring and investigation of the underlying mechanisms of resistance. Here, we identified a previously uncharacterized-Cub and Sushi Domain containing Insecticide Resistance (CSDIR) protein and generated evidence for its role in mediating insecticide resistance in the Anopheles stephensi. A strong binding affinity of the CSDIR protein towards different classes of insecticide molecules-malathion (KD 6.43 mM) and deltamethrin (KD 46.7 mM) were demonstrated using MD simulation studies and Surface Plasmon Resonance (SPR) experiments. Further, the recombinant CSDIR913-1190 protein exhibited potent esterase-like activity (a-naphthyl acetate (a-NA)- 1.356 ± 0.262 mM/min/mg and b-naphthyl acetate (b -NA)- 1.777 ± 0.220 mM/min/mg). Interestingly, dsRNAmediated gene silencing of the CSDIR transcripts caused >60% mortality in resistant An. stephensi upon 1-h exposure to deltamethrin and malathion insecticides, compared to the control group. A significant reduction in the esterase-like activity was also observed against a-NA (p = 0.004) and b-NA (p = 0.025) in CSDIR silenced mosquitoes compared to the control group. Using computational analysis and experimental data, our results provided significant evidence of the involvement of the CSDIR protein in mediating insecticide resistance in Anopheles mosquitoes. Thereby making the CSDIR protein, a novel candidate for exploration of novel insecticide molecules. These data would also be helpful in further understanding the development of metabolic resistance by the Anopheles vector. [ABSTRACT FROM AUTHOR]

Simple Summary: Dengue fever, a mosquito-borne disease, is spreading more widely, and traditional methods to control the vector mosquitoes have been ineffective. In Córdoba, Argentina, we studied if involving school students in educational projects could help communities better understand dengue and take steps to prevent it. Working with students and their families showed us that people learned more about the disease and adopted better practices to stop the mosquitoes from breeding. Student engagement was a powerful way to bring this knowledge into homes, leading to positive behavior changes. This research suggests that including these programs into school curricula all year round might help fight dengue in other areas facing similar challenges. Traditional mosquito vector control methods have proved ineffective in controlling the spread of dengue fever. This study aimed to assess the effectiveness of community engagement through student-led science in promoting dengue prevention and socioecological factors in the temperate urban city of Córdoba, Argentina. It assesses community perceptions, knowledge, attitudes, and preventive practices regarding dengue fever and its vector. Results showed a significant increase in knowledge about the vector and the disease and respondents' adoption of good preventive practices. Student-led science was identified as a valuable tool for reaching households and leading to behavior changes at home. Furthermore, the findings highlighted the need for school programs to address vector biology and vector-borne disease prevention all year round. This study provides invaluable insights into the effectiveness of community engagement through student-led science to promote dengue prevention and socioecological factors. The findings suggest that this approach could be used to control the spread in other regions affected by the disease. [ABSTRACT FROM AUTHOR]

Simple Summary: Household surveys of communities for potential oviposition containers by mosquito control teams offer effective mechanisms for reducing arbovirus transmission. Here, we combined standard community surveys with GIS mapping to identify premises with Aedes-positive containers and classify container types near the end of the dry season in Trinidad, West Indies. The entomological indices based on key containers (tanks, drums, tubs/basins/buckets) showed that two of the four locations surveyed were already at a high risk for arbovirus transmission going into the wet season. GIS mapping provided inspection teams with specific locations that had Aedes-positive containers and highlighted premises that were not accessible. This information can facilitate the identification of areas within communities that may be at greater risk and should be prioritized for future surveys and control efforts; it also highlights the need to inform and increase community participation. Dengue and other arboviruses remain a global threat, and enhanced efforts to control the mosquitoes that transmit them are urgently needed. A survey of potential manmade Aedes aegypti (L.) and Aedes albopictus (Skuse) oviposition containers was performed in four communities near the end of the typical dry season in 2018 in Trinidad, West Indies. The purpose was to conduct individual premise surveys and use GIS mapping to visualize premises within communities that had Aedes-positive containers, as this information could be used for the prioritization of mosquito control efforts in potential high risk areas as the wet season progressed. Accessible premises were surveyed following standard inspection protocols used by the Insect Vector Control Division (IVCD), Ministry of Health (MOH). The results indicated that two of the four locations would be at high risk for arbovirus transmission going into the wet season. The GIS mapping of premises with Aedes-positive containers facilitated the identification of potential hot spots for arbovirus transmission risk within communities that should be prioritized for enhanced monitoring and vector control efforts, emphasizing the need to increase community participation in standard surveys by IVCD. [ABSTRACT FROM AUTHOR]

Gravid culicine mosquitoes rely on olfactory cues for selecting breeding sites containing organic detritus. While this capacity of the mosquitoes is used for surveillance and control, the current methodology is unwieldy, unreliable and expensive in time and labour. This study evaluated the dose-dependent attraction and oviposition response of gravid Culex quinquefasciatus to alfalfa infusions. Through combined chemical and electrophysiological analyses, bioactive volatile organic compounds (VOCs) in the headspace of alfalfa infusions, eliciting attraction, were identified. While phenolic and indolic compounds were the most abundant bioactive VOCs, additional VOCs, including a monoterpene, were required to elicit a significant behavioural response to the synthetic odour blend of alfalfa infusions. Comparative analysis with the commercially available mosquito oviposition pheromone (MOP) was also conducted demonstrating that this standardised synthetic alfalfa infusion odour blend offers a promising lure for targeted surveillance and control of Culex mosquitoes, which may contribute to disease prevention and public health protection. [ABSTRACT FROM AUTHOR]

The use of insecticides, primarily pyrethroids, is a pivotal strategy for mosquito control globally. Bioallethrin, the first commercially available volatile pyrethroid, can elicit spatial (i.e., noncontact) repellency to mosquitoes through the coactivation of olfactory receptor neurons and sodium channels. However, the olfactory mechanism of the repellency elicited by bioallethrin in mosquitoes is still unclear. Here, we demonstrated the involvement of AsOBP1 in the bioallethrin repellency in Anopheles sinensis, one of the main vectors of vivax malaria in China and other Southeast Asian countries. The behavioral and electrophysiological analyses in AsOrco−/− mutant found that the spatial repellency elicited by bioallethrin depended on the odorant receptor (OR)‐mediated olfactory pathway. Furthermore, the repellency was reduced in the AsOBP1−/− mutant and a pyrethroid‐resistant strain, in which the expression of AsOBP1 was significantly decreased. Moreover, recombinant AsOBP1 protein bound to bioallethrin in an in vitro competition assay. These results indicate that activation of the AsOBP1‐mediated olfactory pathway is an important component of bioallethrin repellency. Our research lays the foundation for further elucidation into the olfactory mechanism of bioallethrin repellency and the behavioral modifications of pyrethroid‐resistant mosquitoes. [ABSTRACT FROM AUTHOR]

Background: Surveillance of the host–anopheline mosquitoes' interaction is important for assessing malaria transmission risk and guiding vector control. We assume that changes in malaria vector species' feeding habits, as well as the surrounding environment, have a substantial impact on varied malaria transmission. In this study, we determined the vertebrate host feeding patterns of anopheline mosquitoes to characterize entomologic risk factors for malaria in Jabi Tehnan, Northwestern Ethiopia. Methods: Blood-fed anophelines surveyed during malaria surveillance in Jabi Tehnan district of northwestern Ethiopia were utilized in this study. They were collected using Centers for Disease Control and Prevention (CDC) light traps deployed in selected households per village, placed indoors and outdoors, spanning three agroecological settings (dry mountain, plateau, and semiarid highlands) between June 2020 and May 2021. The engorged mosquitoes were analyzed for host blood meal sources and Plasmodium infection via polymerase chain reaction (PCR) and/or sequencing. Infection rates and bovine and human blood indices were calculated and compared for abundant species; between indoors and outdoors and between agroecology using a chi-squared test for equality of proportion in R package at a significant level of p ≤ 0.05. Results: A total of 246 mosquitoes were successfully typed (indoor, 121; outdoor, 125), with greater relative abundance indoors in mountain and plateau highlands, and outdoors in semiarid areas. Despite ecological differences in blood-fed capture rates, cattle served as the most utilized blood meal source by 11 anopheline species with an overall bovine blood index (BBI) of 74.4%. This trend was dictated by Anopheles gambiae s.l. (198/246; BBI = 73.7%), which exhibited the most plastic feeding habits that included humans (human blood index = 15.7%) and other livestock and rodents. A total of five anopheline species (An. gambiae s.l., An. funestus s.l., An. coustani s.l., An. pretoriensis, and An. pharoensis) fed on humans, of which the first three were found infected with Plasmodium parasites. Most of the infected specimens were An. arabiensis (5.6%, 11/198) and had recently fed mainly on cattle (72.7%, 8/11); one each of infected An. funestus s.l. and An. coustani s.l. had fed on humans and cattle, respectively. Conclusions: The results demonstrate communal feeding on cattle by anophelines including primary and secondary malaria vectors. This study also indicates the importance of cattle-targeted interventions for sustainable control of malaria vectors in the study areas. [ABSTRACT FROM AUTHOR]

Aedes aegypti and Aedes albopictus mosquitoes spread major vector-borne viral diseases in tropical and sub-tropical regions of the globe. In this study, we sequenced the genome of Indian Ae. aegypti and Ae. albopictus and mapped to their reference genomes. Comparative genomics were performed between our strain and the reference strains. A total of 14,416,484 single nucleotide polymorphisms (SNPs) and 156,487 insertions and deletions (InDels) were found in Ae. aegypti, and 28,940,433 SNPs and 188,987 InDels in Ae. albopictus. Particular emphasis was given to gene families involved in mosquito digestion, development, and innate immunity, which could be putative candidates for vector control. Serine protease cascades and their inhibitors called serpins, play a central role in these processes. We extracted high-impact variants in genes associated with serine proteases and serpins. This study reports for the first time a high coverage genome sequence data of an Indian Ae. albopictus mosquito. The results from this study will provide insights into Indian Aedes specific polymorphisms and the evolution of immune related genes in mosquitoes, which can serve as a resource for future comparative genomics and those pursuing the development of targeted biopesticides for effective mosquito control strategies. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the chemical composition of essential oils from Myroxylon peruiferum and Eugenia gracillima and determine the larvicidal potential of the oils against Aedes aegypti. Essential oils from the leaves and young stems of M. peruiferum (EOLMP and EOAMP) and the leaves of E. gracillima (EOLEG) were obtained through hydrodistillation. The major constituents of EOLMP were α-pinene (18.0%) and δ-cadinene (14.2%); the major constituents of EOAMP were spathulenol (22.9%) and β-elemene (12.4%) and the major constituents of EOLEG were δ-elemene (40.4%) and germacrene D (25.2%). The two oils extracted from M. peruiferum were very active against A. aegypti larvae and had similar lethal concentrations (LC50 = 0.7 mg/mL). The oil extracted from E. gracillima had an LC50 of 1.51 mg/mL. The essential oils from M. peruiferum and E. gracillima constitute promising sources for the formulation of novel insecticides for the control of the mosquito Aedes aegypti. [ABSTRACT FROM AUTHOR]

To gain insights into the effectiveness of the newly proposed and developed genetic sterile insect technique in control of mosquitoes, that releases mosquitoes carrying a dominant lethal (RIDL), we formulate discrete-time models based on difference equations. We incorporate, respectively, the four release strategies, early acting bisex (EBS), late acting bisex (LBS), early acting female-killing (EFK), and late acting female-killing (EFK) lethality in the models. We investigate the existence and stability of positive fixed points and derive a release threshold of sterile mosquitoes for each model. We compare the different release strategies by numerical examples. [ABSTRACT FROM AUTHOR]

Dengue fever as a mosquito-borne disease caused by dengue virus is responsible for a substantial disease burden to the world. Wolbachia as an innovative technique has been approved to inhibit the replication of dengue viruses in mosquitoes or reduce the number of wild mosquitoes. We firstly establish a birth-pulse model with sex structures to depict the nonlinear dynamics of mosquito population and then to investigate how Wolbachia can suppress or replace wild mosquitoes. The existence and stability of periodic solutions of the system are proved by analyzing its stroboscopic map. Theoretical results show that under complete maternal transmission, Wolbachia will successfully establish and completely replace wild mosquitoes. Under incomplete maternal transmission, there may be two pairs of bistable periodic solutions, including the coexistence of replacement failure and partial replacement periodic solutions, or the coexistence of replacement failure and mosquito eradication periodic solutions. For these bistable situations, if the initial proportion of Wolbachia-carrying mosquitoes is greater than the critical threshold, then the strategy of partial replacement or mosquito eradication can be succeeded. Since the initial proportion of Wolbachia mosquitoes is not always greater enough in the field, we introduce mosquito releases into the birth-pulse model, and obtain the condition for the stability of complete replacement periodic solution. Finally, we give rich numerical simulations to show the multiple attractors of the systems, the comparison of three common release strategies and the effects of Wolbachia-induced parameters on control strategies. At last section, we summarize some key suggestions on the control of mosquitoes and dengue fever in practice. This work will be helpful for public health authorities in designing proper release strategies to control the spread of dengue fever. • Birth-pulse mosquito population models with sex structures are established. • Dynamics of the systems are investigated by analyzing their stroboscopic map. • Existence for two pairs of bistable periodic solutions are proved and simulated. • Effects of three release methods and control parameters on control strategies are discussed. [ABSTRACT FROM AUTHOR]

Background: Dengue, a mosquito-borne viral disease, has occurred in many cities in China, and it tends to spread to higher latitudes (Huang et al., 2023). Xi'an, situated in central-west China, has witnessed an increase imported cases in the past few years, raising concerns of local dengue transmission. It is crucial to investigate the population density of Aedes albopictus and its insecticides resistance to enhance early warning of dengue fever. Methods: Eight sampling sites in eight counties (YT, BL, WY, CH, YL, LN, LT, ZZ) of Xi'an city were surveyed by larval dipping and human-baited double net trap biweekly from June 2021 to September 2022. The Breteau Index (BI, number of positive containers per 100 houses) and Container Index (CI, the percentage of containers containing larvae or pupae) were used to assess larval density, and the human-baited double net trap (HDN, the number of Ae. albopictus females collected per person per hour) to indicate human bating rate (HBR). Meanwhile, the association between the meteorological factors and mosquito density was analyzed. The Ae. albopictus adult insecticides resistance was evaluated by the World Health Organization (WHO) standard resistance bioassay. Adult females were exposed to insecticide-impregnated paper for 1 h, then transferred to the recovery tube, and mortality rate was calculated after 24 h. According to the Implementation Plan for National Vector Surveillance (2016), resistance status was classified into three levels based on mortality: <80% mortality as resistant, between 80% and 98% mortality as possibly resistant, and >98% mortality as sensitive. Results: From June 2021 to September 2022, a total of 1,065 houses were surveyed for water holding containers, and 99 of 430 water holding containers were checked to be positive for Ae. albopictus larvae and pupae. A total of 1,048 Ae. albopictus females were collected. The average BI, CI and HBR were 10.39, 21.41, and 11.20 female/man/hour in 2021 and 8.86, 20.86, and 11.63 f/m/h in 2022, respectively. The findings showed that the BI exceeded 5 in most months and reached above 20 in specific months. The CI varied in different months and monitoring sites, with the highest CI in August 2021 and July 2022. The discarded tires had the highest positivity rate, with up to 40.32% testing positive for Ae. albopictus larvae. The monthly average temperature showed a positive correlation with CI (r = 0.77), and the monthly BI was positively associated with CI (r = 0.93). The BI, CI, and HBR were significantly higher in the rainy season than other seasons. The bioassay results showed that the mortality rate of Ae. albopictus at the YT monitoring site was 76.92%, indicating resistance to deltamethrin. The mortality rate of Ae. Albopictus at BL, WY, CH, YL, LN, LT, and ZZ sampling sites were varying from 81.25%∼100%, suggesting possibly resistant or still sensitive to beta-cypermethrin, alpha-cypermethrin, malathion, chlorpyrifos, and propoxur. [ABSTRACT FROM AUTHOR]

Mosquitoes are significant vectors of deadly diseases such as malaria and dengue, contributing to approximately 300,000 deaths annually, according to the World Health Organization (WHO). Traditional chemical repellents, while effective, often cause severe allergic reactions and contribute to mosquito resistance. This study explores the formulation of GAP-F essential oil-loaded microspheres as a natural and eco-friendly alternative for mosquito repellency. Essential oils have demonstrated insect-repellent properties; however, their volatility limits their effectiveness. Microencapsulation is employed to protect these oils from degradation and facilitate sustained release, enhancing their efficacy against mosquitoes. GAP-F essential oil was sourced from the CSIR-CIMAP laboratory through distillation. Laboratory tests were conducted to evaluate its effectiveness against Aedes aegypti, Anopheles stephensi and wild mosquitoes. At a concentration of 10%, GAP-F essential oil exhibited repellency rates of 70%, 85% and 75% against these species during a one-hour bioassay. Given the volatile nature of essential oils, the formulation of microspheres serves as a protective carrier that enhances stability and prolongs the duration of protection. The essential oil-loaded microspheres demonstrated satisfactory results in terms of repellency, showing effectiveness rates of 56.66%, 51.66% and 55% against Aedes aegypti, Anopheles stephensi and wild mosquitoes, respectively, during the same duration. Mosquitoes aged between three to five days were used for the bioassay. This research highlights the potential of microencapsulated natural repellents as a viable alternative to chemical products in mosquito control strategies, providing an effective solution that minimizes health risks while addressing the growing concern of insecticide resistance in mosquito populations. [ABSTRACT FROM AUTHOR]

Filariasis is a neglected tropical ailment that is among the oldest on Earth. It causes deformities and has a low fatality rate, but it causes a wide spectrum of clinical symptoms and a high morbidity rate, which causes society to stigmatise the disease. The underlying cause of this medical illness is nematode worms, which are thread-like worms that are categorised according to their presence in vertebrate hosts. Mansonella ozzardi and Onchocerca volvulus are members of the body cavity group, Brugia malayi and Brugia timori are members of the lymphatic group, and Onchocerca streptocerca and Loa loa are members of the cutaneous group. Several pathological problems accompany the mosquito-borne illness lymphatic filariasis, which is among the most common diseases in tropical and subtropical areas. Research into filariasis has advanced rapidly in recent years, shedding light on the parasite's genetics, the host-parasite dynamic, the disease's pathophysiology and the efficacy of treatment. To avoid side effects and provide permanent relief from the aforementioned filarial infections, which cannot be achieved with the marketed drug-therapy, there is a need for an alternative herbal medicinal therapy for filariasis, even though there are marketed preparations for the treatment. Consequently, the plant items that have been shown to be effective against severe filarial infections are the focus of this review. [ABSTRACT FROM AUTHOR]

Wolbachia are the most spread bacterial endosymbionts in the world. These bacteria can manipulate host reproduction or block virus transmission in mosquitoes. For this reason, Wolbachia-based strategies for vector control are seriously considered or have already been applied in several countries around the world. In South America, Wolbachia have been studied in human pathogen vectors such as sand flies and mosquitoes. In French Guiana, the diversity and distribution of Wolbachia are not well known in mosquitoes. In this study, we screened for Wolbachia natural infection in mosquitoes in French Guiana by using 16S rRNA, Wolbachia surface protein (WSP), and multi-locus sequence typing (MLST) molecular assays. A total of 29 out of 44 (65.9%) mosquito species were positive for natural Wolbachia infection according to the PCR results, and two Wolbachia strains co-infected three specimens of Mansonia titillans. Then, we analyzed the phylogenetic relationships among the Wolbachia detected. All of the tested specimens of Aedes aegypti, the major dengue vector of French Guiana, were negative. These results regarding Wolbachia strain, distribution, and prevalence in mosquitoes from French Guiana highlight Wolbachia–mosquito associations and pave the way for a future Wolbachia-based strategy for vector control in this Amazonian territory. [ABSTRACT FROM AUTHOR]

Mosquito-borne diseases such as dengue and filariasis are a growing public health concern in endemic countries. Biological approaches, such as the trans-infection of Wolbachia pipientis in mosquitoes, are an alternative vector control strategy, especially for arthropod-borne viruses such as dengue. In the present study, the effect of Wolbachia (wMel strain) on the vectorial capacity of Aedes aegypti for Dirofilaria immitis was studied. Our results showed that Wolbachia does not affect the phenotype of mosquito survival or the prevalence, number, and molting rate of third-stage larvae in both susceptible and resistant strains of Ae. aegypti. RNA-seq analysis of Malpighian tubules at 2 days post-infection with D. immitis showed the differentially expressed genes (DEGs) with and without wMel infection. No characteristic immune-related gene expression patterns were observed among the DEGs. No significant change in the amount of Wolbachia was observed in the Ae. aegypti after D. immitis infection. Our results suggest that infection of D. immitis in Ae. aegypti populations will not interfere with Wolbachia-based vector control strategies in dengue-endemic areas where cases of D. immitis are present. This study demonstrated the veterinary medical validity of a dengue control program using Wolbachia. [ABSTRACT FROM AUTHOR]

Aedes mosquito-borne viruses (ABVs) place a substantial strain on public health resources in the Americas. Vector control of Aedes mosquitoes is an important public health strategy to decrease or prevent spread of ABVs. The ongoing Targeted Indoor Residual Spraying (TIRS) trial is an NIH-sponsored clinical trial to study the efficacy of a novel, proactive vector control technique to prevent dengue virus (DENV), Zika virus (ZIKV), and chikungunya virus (CHIKV) infections in the endemic city of Merida, Yucatan, Mexico. The primary outcome of the trial is laboratory-confirmed ABV infections in neighborhood clusters. Despite the difficulties caused by the COVID-19 pandemic, by early 2021 the TIRS trial completed enrollment of 4,792 children aged 2–15 years in 50 neighborhood clusters which were allocated to control or intervention arms via a covariate-constrained randomization algorithm. Here, we describe the makeup and ABV seroprevalence of participants and mosquito population characteristics in both arms before TIRS administration. Baseline surveys showed similar distribution of age, sex, and socio-economic factors between the arms. Serum samples from 1,399 children were tested by commercially available ELISAs for presence of anti-ABV antibodies. We found that 45.1% of children were seropositive for one or more flaviviruses and 24.0% were seropositive for CHIKV. Of the flavivirus-positive participants, most were positive for ZIKV-neutralizing antibodies by focus reduction neutralization testing which indicated a higher proportion of participants with previous ZIKV than DENV infections within the cohort. Both study arms had statistically similar seroprevalence for all viruses tested, similar socio-demographic compositions, similar levels of Ae. aegypti infestation, and similar observed mosquito susceptibility to insecticides. These findings describe a population with a high rate of previous exposure to ZIKV and lower titers of neutralizing antibodies against DENV serotypes, suggesting susceptibility to future outbreaks of flaviviruses is possible, but proactive vector control may mitigate these risks. [ABSTRACT FROM AUTHOR]

Background: The control and prevention of mosquito-borne diseases is mostly achieved with insecticides. However, their use has led to the rapid development and spread of insecticide resistance worldwide. Health experts have called for intensified efforts to find new approaches to reduce mosquito populations and human-mosquito contact. A promising new tool is the use of electrical fields (EFs), whereby mosquitoes are repelled by charged particles in their flight path. Such particles move between two or more conductors, and the use of uninsulated copper or aluminum plates as conductors has been proven to be effective at repelling mosquitoes. Here, for the first time, we assess if EFs generated using a single row of insulated conductor wires (ICWs) can also successfully repel mosquitoes, and whether mosquitoes are equally repelled at the same EF strength when the electrodes are a) orientated differently (horizontal vs. vertical placement), and b) spaced more apart. Methodology/Principal findings: Over a period of 23 hours, the number of host-seeking female Aedes aegypti mosquitoes that were successfully repelled by EFs, using ICWs, at EF strengths ranging from 0 kV/cm (control) to 9.15 kV/cm were quantified. Mosquitoes were released inside a 220×220×180 cm room and lured into a BG-Pro trap that was equipped with a BG-counter and baited with CO2 using dry ice. Mosquitoes had to pass through an EF window, that contained a single row of ICWs with alternating polarity, to reach the bait. The baseline interaction between EF strength and repellency was assessed first, after which the impact of different ICW orientations and ICW distances on repellency were determined. Over 50% of mosquitoes were repelled at EF strengths of ≥ 3.66 kV/cm. A linear regression model showed that a vertical ICW orientation (vertical vs. horizontal) had a small but insignificant increased impact on mosquito repellency (p = 0.059), and increasing ICW distance (while maintaining the same EF strength) significantly reduced repellency (p = 0.01). Conclusions/Significance: ICWs can be used to generate EFs that partially repel host-seeking mosquitoes, which will reduce human-mosquito contact. While future studies need to assess if (i) increased repellency can be achieved, and (ii) a repellency of 50–60% is sufficient to impact disease transmission, it is encouraging that EF repellency using ICWs is higher compared to that of some spatial repellent technologies currently in development. This technology can be used in the housing improvement toolkit (i.e. preventing mosquito entry through eaves, windows, and doors). Moreover, the use of cheap, over-the-counter ICWs will mean that the technology is more accessible worldwide, and easier to manufacture and implement locally. Author summary: Mosquito-borne diseases cause significant public health challenges worldwide. To control and prevent the spread of these diseases, mainly insecticides are used to reduce the mosquito population sizes and/or prevent human-mosquito contact. However, their excessive usage has led to the rapid development of insecticide resistance which warrants the need for the development of new mosquito control tools. This study investigates the use of electric fields that are created between insulated conductor wires to repel Aedes aegypti mosquitoes. We found that electric fields can effectively repel over 50% of host-seeking female Aedes aegypti mosquitoes at electric field strengths of ≥ 3.66 kV/cm. There are several advantages to using this novel mosquito control tool, which includes the affordability and accessibility of wires, making the technology suitable for widespread implementation especially in low-middle income countries that are mostly affected by mosquito-borne diseases. This technology has the potential to reduce human-mosquito contact which is a critical factor in mosquito-borne disease transmission. [ABSTRACT FROM AUTHOR]

Background: Microbial larvicides containing both LysiniBacillus sphaericus and Bacillus thuringiensis svar. israelensis (Bti) insecticidal crystals can display advantages for mosquito control. This includes a broader action against larvae that are refractory to the Binary (Bin) toxin from L. sphaericus, as Bin-resistant Culex quinquefasciatus and Aedes aegypti naturally refractory larvae, which often co-habit urban areas of endemic countries for arboviruses. Our principal goal was to assess the toxicity of a combined L. sphaericus/Bti larvicide (Vectomax FG™) to Cx. quinquefasciatus (susceptible CqS and Bin-resistant CqR) and Ae. aegypti (Rocke) and to determine its persistence in the breeding sites with those larvae. Methods: The toxicity of a combined L. sphaericus/Bti product (VectoMax FG™) to larvae was performed using bioassays, and persistence was evaluated in simulate field trials carried out under the shade, testing two label concentrations during 12 weeks. A laboratory strain SREC, established with CqS and CqR larvae, was kept during four generations to evaluate the ability of the L. sphaericus/Bti to eliminate resistant larvae. Results: The L. sphaericus/Bti showed toxicity (mg/L) to larvae from all strains with a decreasing pattern for CqS (LC50 = 0.006, LC90 = 0.030), CqR (LC50 = 0.009, LC90 = 0.069), and Rocke (LC50 = 0.042, LC90 = 0.086). In a simulated field trial, the larvicide showed a persistence of 6 weeks and 8 weeks, controlling larvae from all strains in containers with 100 L of water, using 2 g or 4 g per container (100 L), respectively. The treatment of SREC larvae with L. sphaericus/Bti showed its capacity to eliminate the Bin-resistant individuals using suitable concentrations to target those larvae. Conclusions: Our results showed the high efficacy and persistence of the L. sphaericus/Bti larvicide to control Cx. quinquefasciatus and Ae. aegypti that might cohabit breeding sites. These findings demonstrated that such larvicides can be an effective tool for controlling those species in urban areas with a low potential for selecting resistance. [ABSTRACT FROM AUTHOR]

Background: Aedes albopictus, commonly known as the Asian tiger mosquito, has become one of the most invasive mosquito species. Over the last 5 decades, it has been introduced and established in various tropical and temperate regions worldwide. First reported in Europe in 1979 in Albania and later in Italy in 1990, the species is now established in 13 European Union (EU)/European Economic Area (EEA) countries and 337 regions (2023). In Portugal, Ae. albopictus was first detected in the Algarve and Penafiel regions in 2017, followed by Alentejo in 2022 and Lisbon in 2023. This mosquito species poses a significant public health risk as a vector for numerous pathogenic viruses, including dengue, Zika, and chikungunya. Methods: Aedes albopictus collected in Lisbon in 2023 were analyzed using cytochrome c oxidase I (COX) gene sequencing to understand their genetic relationships. Results: Our data indicate that the Ae. albopictus mosquito populations detected in three locations in Lisbon in 2023 correspond to recent but distinct introduction events. Conclusions: Although there has been no local transmission of Aedes-transmitted viruses in mainland Portugal to date, the spread of the mosquito and increased international travel increase the risk of Aedes-borne disease outbreaks. The ongoing spread of Ae. albopictus in the country and the confirmed multiple introductions in new locations raise awareness of the need to monitor mosquito vectors to control and prevent autochthonous Aedes-borne disease outbreaks. [ABSTRACT FROM AUTHOR]

Dengue, a zoonotic viral disease transmitted by Aedes mosquitoes, poses a significant public health concern throughout the Lao People's Democratic Republic (Lao PDR). This study aimed to describe spatial–temporal patterns and quantify the effects of environmental and climate variables on dengue transmission at the district level. The dengue data from 2015 to 2020 across 148 districts of Lao PDR were obtained from the Lao PDR National Center for Laboratory and Epidemiology (NCLE). The association between monthly dengue occurrences and environmental and climate variations was investigated using a multivariable Zero-inflated Poisson regression model developed in a Bayesian framework. The study analyzed a total of 72,471 dengue cases with an incidence rate of 174 per 100,000 population. Each year, incidence peaked from June to September and a large spike was observed in 2019. The Bayesian spatio-temporal model revealed a 9.1% decrease (95% credible interval [CrI] 8.9%, 9.2%) in dengue incidence for a 0.1 unit increase in monthly normalized difference vegetation index at a 1-month lag and a 5.7% decrease (95% CrI 5.3%, 6.2%) for a 1 cm increase in monthly precipitation at a 6-month lag. Conversely, dengue incidence increased by 43% (95% CrI 41%, 45%) for a 1 °C increase in monthly mean temperature at a 3-month lag. After accounting for covariates, the most significant high-risk spatial clusters were detected in the southern regions of Lao PDR. Probability analysis highlighted elevated trends in 45 districts, emphasizing the importance of targeted control strategies in high-risk areas. This research underscores the impact of climate and environmental factors on dengue transmission, emphasizing the need for proactive public health interventions tailored to specific contexts in Lao PDR. [ABSTRACT FROM AUTHOR]

Background: Certain mosquitoes are known as dominant vectors worldwide, and transmit infectious diseases. The expansion of mosquito habitats due to climate change and increased human activities poses a significant health threat by facilitating the spread of various non-native infectious diseases. This study focused on the detection of the Southeast Asian mosquito species, Aedes (Mucidus) laniger (Wiedemann, 1820) on Jeju Island, the southernmost region of the Republic of Korea (ROK), highlighting the potential risks associated with the spread of vector-borne diseases, particularly emphasizing the elevated likelihood of invasion by Southeast Asian mosquitoes. Methods: Field surveys were conducted in August 2023 on Jeju Island. Adult mosquitoes were collected using BG-sentinel traps and identified to the species level using taxonomic keys. Morphological and molecular analyses were employed to confirm species designations. Molecular data, including mitochondrial and nuclear genes, were used for phylogenetic analysis, which was performed to compare and identify among recorded subgenera in ROK. Species distribution modeling for Ae. laniger was performed to predict potential habitats using R package 'BIOMOD2'. Results: The two specimens of Ae. laniger were collected for the first time on Jeju Island. Morphological and molecular analyses confirmed the identity of this species within the subgenus Mucidus and validated the first record of this species in the ROK. We employed a simple multigene phylogenetic analysis to confirm a new mosquito record at the genus and subgenus levels, finally validating the consistency between morphological identification and molecular phylogenetic outcomes. Furthermore, we have updated the taxonomic keys for the genus Aedes in the ROK, and revised mosquito lists for Jeju Island, incorporating the inclusion of Ae. laniger. On the basis of species distribution modeling, the area of suitable habitat for Ae. laniger is expected to expand due to climate change, but this change did not appear to be meaningful in East Asia. Conclusions: This case offers the first report of the Southeast Asian mosquito, Ae. laniger, in the ROK. The detection of this species on Jeju Island suggests the potential establishment of a breeding population their habitat and raises concerns about further expansion into the Korean Peninsula. Considering the annual occurrence of mosquito-borne disease cases in the Southeast Asia, it is essential to conduct monitoring not only in Jeju Island, where Ae. laniger has been identified, but also across the entire Korean Peninsula. [ABSTRACT FROM AUTHOR]

Background: Antananarivo, the capital city of Madagascar, is experiencing a steady increase in population growth. Due to the abundance of mosquito vectors in this locality, the population exposed to mosquito-borne diseases is therefore also increasing, as is the risk of epidemic episodes. The aim of the present study was to assess, in a resource-limited setting, the information on mosquito population dynamics and disease transmission risk that can be provided through a longitudinal entomological study carried out in a multi-host single site. Methods: Mosquitoes were collected every 15 days over 16 months (from January 2017 to April 2018) using six CDC-light traps in a peri-urban area of Antananarivo. Multivariable generalised linear models were developed using indoor and outdoor densities of the predominant mosquito species as response variables and moon illumination, environmental data and climatic data as the explanatory variables. Results: Overall, 46,737 mosquitoes belonging to at least 20 species were collected, of which Culex antennatus (68.9%), Culex quinquefasciatus (19.8%), Culex poicilipes (3.7%) and Anopheles gambiae sensu lato (2.3%) were the most abundant species. Mosquito densities were observed to be driven by moon illumination and climatic factors interacting at different lag periods. The outdoor models demonstrated biweekly and seasonal patterns of mosquito densities, while the indoor models demonstrated only a seasonal pattern. Conclusions: An important diversity of mosquitoes exists in the peri-urban area of Antananarivo. Some well-known vector species, such as Cx. antennatus, a major vector of West Nile virus (WNV) and Rift-Valley fever virus (RVFV), Cx. quinquefasciatus, a major vector of WNV, Cx. poicilipes, a candidate vector of RVFV and An. gambiae sensu lato, a major vector of Plasmodium spp., are abundant. Importantly, these four mosquito species are present all year round, even though their abundance declines during the cold dry season, with the exception of Cx. quinquefasciatus. The main drivers of their abundance were found to be temperature, relative humidity and precipitation, as well as—for outdoor abundance only—moon illumination. Identifying these drivers is a first step towards the development of pathogen transmission models (R0 models), which are key to inform public health stakeholders on the periods of most risk for vector-borne diseases. [ABSTRACT FROM AUTHOR]

The two main Afrotropical malaria vectors - Anopheles coluzzii and An. gambiae – are genetically distinct and reproductively isolated across West Africa. However, populations at the western extreme of their range are assigned as "intermediate" between the two species by whole genome sequence (WGS) data, and as hybrid forms by conventional molecular diagnostics. By exploiting WGS data from 1190 specimens collected across west Africa via the Anopheles gambiae 1000 Genomes network, we identified a putative taxon in the far-west (provisionally named Bissau molecular form), which did not arise by admixture but rather may have originated at the same time as the split between An. coluzzii and An. gambiae. Intriguingly, this taxon lacks insecticide resistance mechanisms commonly observed in the two main species. These findings lead to a change of perspective on malaria vector species in the far-west region with potential for epidemiological implications, and a new challenge for genetic-based mosquito control approaches. Population genomic analyses of 1,190 Afrotropical malaria vector specimens reveal a putative novel taxon within the Anopheles gambiae complex at the western extremes of its range, which may represent a challenge for genetic-based mosquito control [ABSTRACT FROM AUTHOR]

The incidence of vector-borne disease is on the rise globally, with burdens increasing in endemic countries and outbreaks occurring in new locations. Effective mitigation and intervention strategies require models that accurately predict both spatial and temporal changes in disease dynamics, but this remains challenging due to the complex and interactive relationships between environmental variation and the vector traits that govern the transmission of vector-borne diseases. Predictions of disease risk in the literature typically assume that vector traits vary instantaneously and independently of population density, and therefore do not capture the delayed response of these same traits to past biotic and abiotic environments. We argue here that to produce accurate predictions of disease risk it is necessary to account for environmentally driven and delayed instances of phenotypic plasticity. To show this, we develop a stage and phenotypically structured model for the invasive mosquito vector, Aedes albopictus, and dengue, the second most prevalent human vector-borne disease worldwide. We find that environmental variation drives a dynamic phenotypic structure in the mosquito population, which accurately predicts global patterns of mosquito trait-abundance dynamics. In turn, this interacts with disease transmission to capture historic dengue outbreaks. By comparing the model to a suite of simpler models, we reveal that it is the delayed phenotypic structure that is critical for accurate prediction. Consequently, the incorporation of vector trait relationships into transmission models is critical to improvement of early warning systems that inform mitigation and control strategies. There is a need for accurate models to predict disease dynamics by considering the interactions between environment and vector traits. This study finds that incorporating delayed phenotypic plasticity in mosquito traits significantly enhances the accuracy of dengue risk predictions. [ABSTRACT FROM AUTHOR]

In this paper, biodiversity and a saturation treatment rate are introduced into a type of mosquito-borne infectious disease model with an incubation time delay. Through the dynamical analysis of the model, conditions for the existence and stability of disease-free and endemic equilibria are determined. The basic reproduction number of the model is calculated, and the condition for the existence of backward bifurcation is outlined. The study finds that under the dual influence of biodiversity and saturation treatment, the threshold characteristic of the basic reproduction number becomes invalidated. When R 0 is less than 1, the model may exhibit four equilibrium states, with both the disease-free equilibrium and the endemic equilibrium being locally stable. In this scenario, whether the virus will become extinct depends on the initial conditions. The study also finds that when the basic reproduction number R 0 is greater than 1, the stability of the model is influenced by the time delay, with Hopf bifurcation occurring at a specific time delay. In addition, another novel contribution of this paper is the formulation of an optimal control problem that takes into account the minimization of damage caused by humans to biodiversity. Based on the Pontryagin's maximum principle, the specific characteristics of the optimal control measures are given, and the optimal strategy is derived by comparing five groups of control strategies. The optimal control results highlight the synergistic effect of multiple control measures with biodiversity. Under optimal control, a significant complementary effect between medical inputs and the dilution effect of biodiversity is evident. The findings imply that maintaining high biodiversity levels can decrease the demand for medical resources in mosquito-borne disease control efforts. [ABSTRACT FROM AUTHOR]

Vector-borne diseases resulted into several cases of human morbidity and mortality over the years and among them is filariasis, caused by the mosquito Culex quinquefasciatus. Developing novel strategies for mosquito control without jeopardizing the environmental conditions has always been a topic of discussion and research. Integrated Vector Management (IVM) emphasizes a comprehensive approach and use of a range of strategies for vector control. Recent research evaluated the use of two entomopathogenic fungi; Beauveria bassiana and Lecanicillium lecanii in IVM, which can serve as potential organic insecticide for mosquito population control. However, their combined efficacy has not yet been evaluated against mosquito control in prior research and a gap of knowledge is still existing. So, this research was an attempt to bridge up the knowledge gap by (1) Assessing the combined efficacy of Beauveria bassiana and Lecanicillium lecanii on Culex quinquefasciatus (2) To investigate the sub-lethal concentration (LC50) of the combined fungal concentration and (3) To examine the post-mortem effects caused by the combined fungal concentration under Scanning Electron Microscope (SEM). The larval pathogenicity assay was performed on 4th instar C. quinquefasciatus larvae. Individual processed fungal solution of B. bassiana and L. lecanii were procured and to test the combined efficacy, the two solutions were mixed in equal proportions. To evaluate the sub-lethal concentration (LC50), different concentrations of the combined fungal solution were prepared by serial dilations. The mortality was recorded after 24 hours for each concentration. Upon treatment and evaluation, The LC50 values of B. bassiana and L. lecanii were 0.25 x 104 spores/ml and 0.12 x 104 spores/ml respectively and the combined fungal concentration was 0.06 x 103 spores/ml. This clearly indicated that the combined efficacy of the fungi is more significant. Further, SEM analysis revealed morphological deformities and extensive body perforations upon combined fungal treatment. These findings suggested that combining the two fungi can be a more effective way in controlling the population of Culex quinquefasciatus. [ABSTRACT FROM AUTHOR]

The mosquito microbiome significantly influences vector competence, including in Aedes albopictus, a globally invasive vector. Describing the microbiome and Wolbachia strains of Ae. albopictus from different regions can guide area-specific control strategies. Mosquito samples from Spain and São Tomé were analyzed using 16S rRNA gene sequencing and metagenomic sequencing. Wolbachia infection patterns were observed by sex and population. Female mosquitoes were blood-fed, a factor considered in analyzing their microbiota. Results revealed a dominance of dual Wolbachia infections, strains A and B, in the microbiome of both populations of Ae. albopictus, especially among females. Both populations shared a core microbiome, although 5 and 9 other genera were only present in Spain and São Tomé populations, respectively. Genera like Pelomonas and Nevskia were identified for the first time in Aedes mosquitoes. This study is the first to describe the Ae. albopictus bacteriome in Spain and São Tomé, offering insights for the development of targeted mosquito control strategies. Understanding the specific microbiome composition can help in designing more effective interventions, such as microbiome manipulation and Wolbachia-based approaches, to reduce vector competence and transmission potential of these mosquitoes. [ABSTRACT FROM AUTHOR]

Simple Summary: The study is about tracking different types of mosquitoes and the spread of the invasive Asian tiger mosquito on the remote Greek island of Kastellorizo. The research aims to understand how widespread these mosquitoes are and how prepared the local community is to deal with them. We conducted KAP (knowledge, attitude, practices) surveys, set up mosquito traps, and identified the types of mosquitoes found. The surveys revealed the need for increased public education about these health risks. The mosquito traps confirmed the presence of species such as Aedes albopictus, which can play a role in the spread of various diseases, along with other species like Culex pipiens, which is the main vector of West Nile virus. The study concludes that involving the community in mosquito monitoring is crucial in regard to helping control the mosquito population. These findings are valuable because they provide essential information for creating effective mosquito control strategies in isolated areas, ultimately helping to protect public health by reducing the risk of disease outbreaks. The expansion of the tiger mosquito, a vector that can transmit diseases such as dengue, chikungunya, and Zika virus, poses a growing threat to global health. This study focuses on the entomological surveillance of Kastellorizo, a remote Greek island affected by its expansion. This research employs a multifaceted approach, combining KAP survey (knowledge, attitude, practices), mosquito collection using adult traps and human landing catches, and morphological and molecular identification methods. Results from questionnaires reveal community awareness and preparedness gaps, emphasizing the need for targeted education. Mosquito collections confirm the presence of the Aedes albopictus, Aedes cretinus, and Culex pipiens mosquitoes, highlighting the importance of surveillance. This study underscores the significance of community engagement in entomological efforts and proposes a citizen science initiative for sustained monitoring. Overall, this research provides essential insights for developing effective mosquito control programs in remote island settings, thereby emphasizing the importance of adopting a One Health approach to mitigate the spread of vector-borne diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: Mosquito vector research and population control strategies are supported by the rearing of species like Aedes aegypti, commonly known for propagating yellow fever. Colonies of Ae. aegypti are typically reared on fresh animal bloods to supply nutrients including iron, sodium chloride, and albumin necessary for reproduction. However, fresh animal blood is difficult to handle, store, and transport, and its use in rearing is limited to two weeks post-collection. The present study reports on the identification of an inexpensive, shelf-stable spray-dried porcine blood (SDPB) product containing accessible hemoglobin that demonstrated usefulness in a simple mosquito alternative meal (AM) formulation. Quantitative evidence that the phagostimulant in SDPB is hemoglobin was obtained through chromatography assays and the elimination of other feeding stimulants as potential candidates. Ae. aegypti observably engorged upon and produced eggs when fed the AM, which was also shown to sustain multiple colony generations with offspring viable through the larval and pupal stages. SDPB-based AMs may develop into platforms for studying the rearing of hematophagous insects with the potential to expand the capabilities of resource-intensive population control strategies. Research into mosquito-borne illnesses faces hurdles because feeding fresh animal blood to rear female mosquitoes presents logistical, economic, and safety challenges. In this study, a shelf-stable additive (spray-dried porcine blood; SDPB) hypothesized to supply accessible hemoglobin was evaluated within an alternative meal (AM) containing whey powder and PBS for rearing the yellow fever mosquito Aedes aegypti. LC–MS/MS proteomics, microbial assays, and particle reduction techniques confirmed and characterized the functionality of hemoglobin in SDPB, while engorgement, fecundity, egg viability, and meal stability bioassays assessed AM performance. Chemical assays supported hemoglobin as the phagostimulant in SDPB with aggregates partially solubilized in the AM that can be more accessible via particle reduction. Unpaired two-tailed t-tests indicate that the AM stimulates oogenesis (t11 = 13.6, p = 0.003) and is stable under ambient (1+ y; t12 = 0.576, p = 0.575) and aqueous (14 d; t12 = 0.515, p = 0.639) conditions without decreasing fecundity. Egg hatch rates for the ninth generation of AM-reared Ae. aegypti were 50–70+%. With further development, this meal may serve as a platform for mass rearing or studying effects of nutritional additives on mosquito fitness due to its low cost and stability. Future work may examine tuning spray drying parameters and resulting impacts on hemoglobin agglomeration and feeding. [ABSTRACT FROM AUTHOR]

Simple Summary: Organic insecticides against Aedes aegypti L. mosquitoes are regarded as one of the most important tools for containing arboviruses transmitted by this species, such as dengue, Zika, and chikungunya in tropical countries including Thailand, considering the development of mosquito resistance to synthetic chemical larvicides. The most critical way to contain outbreaks is to control the vector that transmits pathogens. Monoterpenes are new, effective, and eco-friendly alternatives. This study investigated the larvicidal and pupicidal activities of two monoterpenes—geranial and trans-cinnamaldehyde—and their combinations. The efficacies of each formulation were compared against each other and temephos. Binary mixtures were significantly more effective than single formulations or temephos. They are safe for the non-target aquatic predator, guppies (Poecilia reticulata). These combinations make excellent insecticides for both larvae and pupae mosquito vector control, and the results open up the opportunity for both compounds to be developed into eco-friendly products. Monoterpenes are effective and eco-friendly alternatives to conventional chemical larvicides. We tested single and binary mixtures of monoterpenes—geranial and trans-cinnamaldehyde—for their larvicidal and pupicidal activities against Aedes aegypti L. and for non-target toxicity on guppies (Poecilia reticulata Peters), using 1% (w/w) temephos as a reference. Geranial and trans-cinnamaldehyde at 250 ppm showed stronger larvicidal and pupicidal activities with a 100% mortality rate and an LT50 ranging from 0.3 to 0.6 h. All combinations were strongly synergistic against larvae and pupae compared to single formulations, with an increased mortality value (IMV) of 6% to 93%. The combination of geranial + trans-cinnamaldehyde (1:1) at 200 ppm showed the highest impact, with an IMV of 93%. The strongest larvicidal and pupicidal activities, a 100% mortality rate, and an LT50 of 0.2 h were achieved by geranial + trans-cinnamaldehyde (1:1) 500 ppm. They were thirty times more effective than a 1% temephos solution (LT50 ranging from 6.7 to 96 h) and caused obviously shriveled cuticles and a swollen respiratory system. All single and binary mixtures were not toxic to the guppies. Thus, the combination of geranial + trans-cinnamaldehyde has great potential as a safe insecticide for controlling mosquito larvae and pupae. [ABSTRACT FROM AUTHOR]

Simple Summary: In the global fight against malaria, standard mosquito control tools are designed to protect indoor spaces where people live and sleep. However, indoor residual spraying (IRS) and insecticide-treated nets (ITNs) can still leave individuals vulnerable to mosquito-borne pathogen transmission, especially outdoors, where few studies have been conducted. Even with ITNs and IRS in place, Nchelenge District in northern Zambia experiences persistently high malaria transmission. To assess the diversity and abundance of outdoor foraging female anopheline mosquitoes, light traps were used as proxy measures for mosquito host-seeking, set in three outdoor trapping schemes randomly assigned on different nights: (1) locations where people congregate outdoors at night, (2) animal pens, and (3) high-human-traffic areas, such as paths to latrines, where traps were baited with an artificial scent lure. The most important vectors of malaria parasites, Anopheles funestus sensu stricto (s.s.) (86%) and An. gambiae s.s. (2%), accounted for most of the 1087 female anophelines captured, with a highly diverse sampling of other anophelines making up the remainder. No significant difference in species diversity or female anopheline abundance was detected between trapping schemes, and malaria parasites were detected only in An. funestus. The challenges to malaria control in Nchelenge District may be explained, in part, by the observed outdoor foraging of anopheline mosquitoes. Light traps baited with the artificial lure demonstrated potential for outdoor collections of malaria mosquitoes in resource-poor settings. In the global fight against malaria, standard vector control methods such as indoor residual spraying (IRS) and insecticide-treated nets (ITNs) are intended to protect inside residential structures and sleeping spaces. However, these methods can still leave individuals vulnerable to residual transmission from vectors that they may be exposed to outdoors. Nchelenge District in northern Zambia experiences persistently high malaria transmission even with ITNs and IRS in place. However, very few studies have examined outdoor vector activity. To assess the diversity and abundance of outdoor foraging female anopheline mosquitoes, CDC light traps were used as proxy measures for mosquito host-seeking, set in three outdoor trapping schemes randomly assigned on different nights: (1) locations where people congregate at night outside of the house within the peri-domestic space, (2) animal pens or shelters, and (3) high-human-traffic areas, such as paths to latrines, where traps were baited with BG-Lure®. A total of 1087 total female anophelines were collected over a total of 74 trap nights. Anopheles funestus s.s. comprised the majority of the collection (86%), with An. gambiae s.s. (2%) and a highly diverse sampling of other anophelines (12%) making up the remainder. Plasmodium falciparum parasites were only detected in An. funestus (1%). No significant difference in species diversity or female anopheline abundance was detected between trapping schemes. Outdoor foraging anopheline mosquitoes, including a number of infectious An. funestus, may partially explain the difficulty of controlling malaria transmission in Nchelenge District, where vector control is only targeted indoors. BG-Lure® shows some promise as an alternative to human-baited landing catch collections in this resource-poor setting. [ABSTRACT FROM AUTHOR]