Aegypti Mosquitoes Research Articles

Impact of Diverse Musical Genres on Blood-Feeding and Mating Behavior in Aedes aegypti Mosquitoes.

Sound plays an important role in mosquito foraging and sexual interactions. Mosquitoes utilize acoustic signals for host location, sexual recognition, and mating, which is achieved through the rhythmic beating of their wings to generate distinct sounds characterized by specific flight tone frequencies. In this study, electronic music (Tremor by Dimitri Vegas, Martin Garrix and Like Mike) and country music (Country Road by John Denver) were played in high and low volumes to investigate the influence of different genres of music on the blood feeding and mating responses of Ae. aegypti. The observations encompassed monitoring the landing attempts, blood-feeding endeavors, and mating behavior of Ae. aegypti. High-volume electronic and country music with elevated pitch and amplitude significantly reduced host attacks and blood-feeding attempts by female mosquitoes compared to low-volume or music-off conditions. However, the significant reduction of successful copula was only observed in Ae. aegypti mosquitoes exposed under electronic music with high volume. As transmission of dengue is through blood feeding and mating, this discovery may open new possibilities for developing music-based control strategies against mosquito-borne diseases.

Wolbachia strain wMelM disrupts egg retention by Aedes aegypti females prevented from ovipositing.

Aedes aegypti mosquitoes are well adapted to dry climates and can retain their eggs for extended periods in the absence of suitable habitat. Wolbachia strains transferred from other insects to mosquitoes can be released to combat dengue transmission by blocking virus replication and spreading through populations, but host fitness costs imposed by Wolbachia, particularly under some environments, can impede spread. We, therefore, assessed the impact of two Wolbachia strains being released for dengue control (wAlbB and wMelM) on fecundity and egg viability following extended egg retention (up to 24 days) under laboratory conditions. Egg viability following retention decreased to a greater extent in females carrying wMelM compared to uninfected or wAlbB females. Fertility fully recovered in uninfected females following a second blood meal after laying retained eggs, while wMelM females experienced only partial recovery. Effects of wMelM on egg retention were similar regardless of whether females were crossed to uninfected or wMelM males, suggesting that fitness costs were triggered by Wolbachia presence in females. The fecundity and hatch proportions of eggs of wMelM females declined with age, regardless of whether females used stored sperm or were recently inseminated. Costs of some Wolbachia strains during egg retention may affect the invasion and persistence of Wolbachia in release sites where larval habitats are scarce and/or intermittent.IMPORTANCEWolbachia mosquito releases are expanding around the world with substantial impacts on dengue transmission. Releases have succeeded in many locations, but the establishment of Wolbachia has been challenging in some environments, and the factors contributing to this outcome remain unresolved. Here, we explore the effects of Wolbachia on a novel trait, egg retention, which is likely to be important for the persistence of mosquito populations in locations with intermittent rainfall. We find substantial impacts of the Wolbachia strain wMelM on the quality of retained eggs but not the wAlbB strain. This cost is driven by the Wolbachia infection status of the female and can partially recover following a second blood meal. The results of our study may help to explain the difficulty in establishing Wolbachia strains at some field release sites and emphasize the need to characterize Wolbachia phenotypes across a variety of traits and strains.

Computer vision: applications in Biomedical Engineering

The focus of this study is the presentation of two systems, which use computer vision techniques. In the first, the authors applied these techniques to the acquisition and processing system of ovitrap images. However, the second system is a physiotherapeutic evaluation platform for dynamic monitoring of body balance. By using a depth image of the patient (based on a 3D camera), the algorithm can predict the exact positions of the joints of an individual, without temporal information. The two studies described presented showed promising results, which demonstrated that computer vision techniques are of great importance. The experiments with the Aedes Aegypti mosquito egg has allowed accurate detection and counting of them. The experiments with body balance analysis has allowed the tracking of the center of mass of an individual during physiotherapeutic exercises. Software has detected the movement of the center of mass, satisfying a physiotherapeutic need. The techniques developed for computer vision have many possible applications in different areas and different populations, not only in the areas presented in this study.

Environmental pollution by plasticizers and the relationship to vector dengue mosquito Aedes aegypti: Bisphenol A (BPA) affect the development and viral immune pathway response

Bisphenol A (BPA) is a widely used industrial chemical found in various products, leading to human exposure through dietary and non-dietary sources. It acts as an endocrine disruptor, affecting reproductive processes in vertebrates by binding to estrogen receptors. While its effects on vertebrates have been extensively studied, much less is known about its impact on invertebrates. This study investigates the effects of BPA on the development and immune response of Aedes aegypti mosquitoes, which are important vectors for arboviral diseases, such as dengue, an emergent viral disease worldwide. Artificial aquatic niches (AAN) were sampled, and BPA concentrations were quantified. Ae. aegypti larvae were exposed to varying BPA concentrations, and their development, fecundity, fertility, and immune response were assessed. Results show delayed development and decreased emergence of mosquitoes exposed to BPA. Females exposed to BPA exhibited reduced oviposition while hatching rates remained unaffected. Furthermore, BPA exposure altered the expression of immune response genes in adult mosquitoes, with differential effects observed between sexes. This suggests that BPA exposure during early developmental stages can modulate the antiviral immune response in adult mosquitoes, possibly through the 20-hydroxyecdysone (20E) signaling pathway. Overall, this study highlights the potential impact of BPA on the development and immune function of mosquito vectors, with implications for vector competence and disease transmission.

Assistance in The Implementation of Ovitrap-Larvitrap In Controlling The Aedes Aegypti Mosquito Population For The Prevention of Dengue Fever (DHF) In Elementary Schools, Poasia District, Kendari City

Assistance in The Implementation of Ovitrap-Larvitrap In Controlling The Aedes Aegypti Mosquito Population For The Prevention of Dengue Fever (DHF) In Elementary Schools, Poasia District, Kendari City

The antiviral JNJ-A07 significantly reduces dengue virus transmission by Aedes aegypti mosquitoes when delivered via blood-feeding.

Dengue virus (DENV) is the most widespread mosquito-borne virus worldwide, but no antiviral therapies are available yet. The pan-serotype DENV inhibitor JNJ-A07 has shown potent activity in a mouse model. It remains unknown whether an antiviral drug ingested by mosquitoes could inhibit virus replication and thus reduce transmission to other hosts. Here, we investigated the antiviral activity of JNJ-A07 when administered in the blood meal to Aedes aegypti mosquitoes. JNJ-A07 blocked DENV-2 transmission by the mosquitoes in both pre-exposure and post-exposure settings. In addition, JNJ-A07 remained in the mosquito bodies for 7 days after blood meal. Reductions of DENV systemic infection in the mosquitoes suggested a potential for decreased proportions of DENV outbreaks in a simulated environment when the mosquitoes ingested JNJ-A07 via the blood meal.

Development of flame retardant slow release insecticides paint and testing its efficacy for four years against dengue and malaria vectors

Insecticide based paint formulations have been available since years, however the concept of using such paint products at household level did not get attention due to various reasons. The advancement in insecticidal paint technology has steered toward the development and evaluation of such formulations for use against arthropod vectors. The improved insecticidal paint formulations may contain two or more active agents, hence could display different type of activity against the target vectors. In the present study, optimum concentrations of deltamethrin (1%), chlorpyriphos (0.5%) and pyriproxyfen (0.075%) were used as active ingredients (AIs) to develop flame retardant slow-release insecticides paint (FRSRIP) formulation. The developed formulation was tested for physico-chemical properties, toxicity and efficacy against two important mosquito vectors. The formulation was glossy, smooth, uniform and scratch proof. Furthermore, the formulation was flame retardant and conformed to class-A according to the guidelines. Acute oral, dermal and inhalation toxicity suggested that the formulation is safe for use in human dwellings. The formulation was evaluated against Ae. aegypti and An. stephensi mosquitoes in laboratory upto four years. It was found that KDT50 after 24 months (T24) was 14.8 ± 0.8 min and 17.1 ± 1.0 min, while after 48 month (T48) was 21.3 ± 2.0 min and 22.4 ± 1.4 min in both Ae. aegypti and An. stephensi respectively. KDT50 was found varying during the different time intervals (T6 to T48) in both Ae. aegypti (p = 0.01) and An. stephensi (p = 0.0003). Furthermore the corrected mortality (CM) also found statistically declined during the period of evaluation (T6 to T48) in both the test species (F ≥ 42. 4; p ≤ 0.0001). Ae. aegypti mosquitoes that survived FRSRIP exposure exhibited overall decline in total eggs laid, eggs hatched, pupae formed and adult emerged at different time intervals upto T21. Behavioural experiments showed that both the tested species elicited negative response to the test formulation. The concentrations of all the three active agents were estimated by HPLC after different time intervals, however only deltamethrin (0.24%) was found after T48. The developed formulation was stable, safe and effective against mosquito vectors for a considerably longer time. In the pretext of continuous toll of vector borne diseases and trans-boundary expansion of mosquito vectors into new geographical areas, the idea of using insecticidal paint could be a game changer.

Dengue virus genomic surveillance in the applying Wolbachia to eliminate dengue trial reveals genotypic efficacy and disruption of focal transmission

Release of Aedes aegypti mosquitoes infected with Wolbachia pipientis (wMel strain) is a biocontrol approach against Ae. aegypti-transmitted arboviruses. The Applying Wolbachia to Eliminate Dengue (AWED) cluster-randomised trial was conducted in Yogyakarta, Indonesia in 2018–2020 and provided pivotal evidence for the efficacy of wMel-Ae. aegypti mosquito population replacement in significantly reducing the incidence of virologically-confirmed dengue (VCD) across all four dengue virus (DENV) serotypes. Here, we sequenced the DENV genomes from 318 dengue cases detected in the AWED trial, with the aim of characterising DENV genetic diversity, measuring genotype-specific intervention effects, and inferring DENV transmission dynamics in wMel-treated and untreated areas of Yogyakarta. Phylogenomic analysis of all DENV sequences revealed the co-circulation of five endemic DENV genotypes: DENV-1 genotype I (12.5%) and IV (4.7%), DENV-2 Cosmopolitan (47%), DENV-3 genotype I (8.5%), and DENV-4 genotype II (25.7%), and one recently imported genotype, DENV-4 genotype I (1.6%). The diversity of genotypes detected among AWED trial participants enabled estimation of the genotype-specific protective efficacies of wMel, which were similar (± 10%) to the point estimates of the respective serotype-specific efficacies reported previously. This indicates that wMel afforded protection to all of the six genotypes detected in Yogyakarta. We show that within this substantial overall viral diversity, there was a strong spatial and temporal structure to the DENV genomic relationships, consistent with highly focal DENV transmission around the home in wMel-untreated areas and a near-total disruption of transmission by wMel. These findings can inform long-term monitoring of DENV transmission dynamics in Wolbachia-treated areas including Yogyakarta.

Potential role of heterologous flavivirus immunity in preventing urban transmission of yellow fever virus

During the recent yellow fever (YF) epidemics in Brazil, human cases were attributed to spillover infections via sylvatic mosquito transmission. Despite YF virus (YFV) transmission in major urban centers with insufficient vaccination coverage and abundant populations of the domestic vector, Aedes aegypti, there was no evidence of human-amplified transmission. Furthermore, the historic absence of YF in Asia, despite abundant Ae. aegypti and an immunologically naive human population, is unexplained. We tested the hypothesis that pre-existing, heterologous flavivirus immunity, specifically from dengue (DENV) and Zika (ZIKV) viruses, limits YFV viremia and transmission by Ae. aegypti. We infected cynomolgus macaques with DENV or ZIKV, then challenged them 6–9 months later with YFV. We then measured viremia and disease and allowed Ae. aegypti mosquitoes to feed during peak macaque viremia. Although prior heterologous immunity had variable effects on disease, DENV and ZIKV immunity consistently suppressed YFV viremia. Despite no statistical difference due to a small sample size, the suppression in viremia led to a significant reduction in Ae. aegypti infection and a lack of transmission potential. These results support the hypothesis that, in DENV- and ZIKV-endemic regions such as South America and Asia, human flavivirus immunity suppresses YFV human amplification potential, reducing the risk of urban outbreaks.

Variable effects of transient Wolbachia infections on alphaviruses in Aedes aegypti.

Wolbachia pipientis (= Wolbachia) has promise as a tool to suppress virus transmission by Aedes aegypti mosquitoes. However, Wolbachia can have variable effects on mosquito-borne viruses. This variation remains poorly characterized, yet the multimodal effects of Wolbachia on diverse pathogens could have important implications for public health. Here, we examine the effects of transient somatic infection with two strains of Wolbachia (wAlbB and wMel) on the alphaviruses Sindbis virus (SINV), O'nyong-nyong virus (ONNV), and Mayaro virus (MAYV) in Ae. aegypti. We found variable effects of Wolbachia including enhancement and suppression of viral infections, with some effects depending on Wolbachia strain. Both wAlbB- and wMel-infected mosquitoes showed enhancement of SINV infection rates one week post-infection, with wAlbB-infected mosquitoes also having higher viral titers than controls. Infection rates with ONNV were low across all treatments and no significant effects of Wolbachia were observed. The effects of Wolbachia on MAYV infections were strikingly strain-specific; wMel strongly blocked MAYV infections and suppressed viral titers, while wAlbB had more modest effects. The variable effects of Wolbachia on vector competence underscore the importance of further research into how this bacterium impacts the virome of wild mosquitoes including the emergent human pathogens they transmit.

Using models and maps to inform Target Product Profiles and Preferred Product Characteristics: the example of Wolbachia replacement.

The global prevalence of diseases transmitted by Aedes aegypti mosquitoes, such as dengue, Zika and Yellow Fever, is increasing, but development of promising new mosquito control technologies could reverse this trend. Target Product Profiles (TPPs) and Preferred Product Characteristics (PPCs) documents issued by the World Health Organization can guide the research and development pathways of new products and product combinations transitioning from proof of concept to operational use. We used high resolution global maps of the case and economic burden of dengue to derive programmatic cost targets to support a TPP for Wolbachia replacement. A compartmental entomological model was used to explore how release size, spacing and timing affect replacement speed and acceptability. To support a PPC for a hybrid suppress-then-replace approach we tested whether Wolbachia replacement could be achieved faster, more acceptably or at a lower cost if preceded by a mosquito suppression programme. We show how models can reveal trade-offs, identify quantitative thresholds and prioritise areas and intervention strategies for further development. We estimate that for Wolbachia replacement to be deployable in enough areas to make major contributions to reducing global dengue burden by 25% (in line with 2030 WHO targets), it must have the potential for cost to be reduced to between $7.63 and $0.24 (USD) per person protected or less. Suppression can reduce the number of Wolbachia mosquitoes necessary to achieve replacement fixation by up to 80%. A hybrid approach can also achieve fixation faster and potentially improve acceptability, but may not justify their cost if they require major new investments in suppression technologies. Here we demonstrate the value dedicated modelling can provide for interdisciplinary groups of experts when developing TPPs and PPCs. These models could be used by product developers to prioritise and shape development decisions for new Wolbachia replacement products.

Pengaruh faktor sosial ekonomi dan lingkungan terhadap prevalensi demam berdarah dengue di wilayah kerja Puskesmas Sangurara, Bulili dan Birobuli Kota Palu

Dengue fever is one of the diseases that is still a problem in Indonesia. The incidence of DHF cases in Central Sulawesi, especially Palu City, has increased every year. Environmental and socio-economic factors affect the breeding of Aedes Aegypti mosquitoes. This study aims to determine the effect of socio[1]economic and environmental conditions on the incidence of DHF in the working areas of Sangurara, Bulili and Birobuli health centers in Palu City, Central Sulawesi. The method used quantitative with cross sectional research design. Sampling using Simple Random Sampling technique. The number of samples was 51 cases and 51 controls. Analysis technique used Chi- Square. From the results of the study, the variables that significantly influenced the incidence of DHF were education (p-value = 0.012), occupation (p-value = 1.000), income (p-value = 0.029), frequency of draining containers (p-value = 0.008), habit of hanging clothes (p-value = 0.031), home environment conditions (p-value = 0.005). While the variables that did not affect the incidence of DHF were the availability of lids on containers (p-value = 1.000), and the presence of larvae in containers (p-value = 0.127). This study concluded that education, income, frequency of container draining, habit of hanging clothes and home environmental conditions had a significant influence on the incidence of DHF and there was no influence between occupation, availability of container lids and the presence of larvae in containers.

Dengue virus transmission during non-outbreak period in Dar Es Salaam, Tanzania: a cross-sectional survey

BackgroundTanzania has experienced multiple dengue outbreaks between 2010 and 2019, caused by various dengue virus (DENV) strains. In 2019, there were 6917 confirmed dengue cases and 13 deaths in Tanzania. Routine diagnosis of dengue fever is unfortunately excluded, particularly during non-outbreak periods, resulting in delayed outbreak detection and control. The aim of this study was to improve early detection and control measures for DENV by investigating its circulation in human and Aedes aegypti (A.aegypti) mosquitoes during the non-outbreak periods in Dar es Salaam, Tanzania, which is an area frequently affected by dengue outbreaks.MethodsFour hundred and fifteen (415) blood samples were collected from patients attending randomly selected health facilities in five wards; Azimio, Keko, Mtoni, Mbagala and Chamazi within Temeke district. The samples were tested for DENV NS1 antigen and anti-dengue IgM and IgG antibodies by rapid test. Then, 150 out of 415 blood samples were tested for the DENV by conventional Reverse Transcriptase Polymerase Chain Reaction (RT-PCR). Two thousand two hundred and fifty (2,250) adult female A.aegypti mosquitoes were collected using a Prokopack aspirator and BG sentinel trap or obtained after rearing immature stages and tested, in pools of 15 for DENV by RT-PCR. Statistical Software, SPSS version 23, was used for data analysis.ResultsOf the tested blood samples, 17% (71/415) were positive by NS1 antigen, 0.5% (2/415) by IgM, 0.5% (2/415) by IgG antibodies, and 0.5% (2/415) by IgM and IgG. None of the samples tested positive by DENV RT-PCR. Moreover, 3.3% (5/150) of tested mosquito pools had DENV by RT-PCR. Individuals aged between 21 and 40 years of age had increased risk of testing positive for DENV NS1 antigen, followed by those aged 5–20 years old, particularly those residing from Azimio ward, Keko ward, Mtoni ward and Mbagala ward, p-value ≤ 0.05.ConclusionFindings from this study revealed evidence of DENV circulation during non-outbreak periods in Dar es Salaam, Tanzania. These findings underscore the importance of including testing for dengue infection in routine differential diagnoses of febrile cases, and also frequent dengue surveillance in mosquitos. This proactive approach will help early DENV outbreak detection and control in the country.

The Physiological Effect Of Zinc Oxide (ZnO) Nanopesticide On Aedes aegypti Larvae

Aedes aegypti is responsible for transmitting various mosquito-borne diseases. Recently, there have been concerns about the negative impacts of the insecticides used in vector control including insecticide resistance development in the mosquito population. These circumstances lead to efforts to develop other strategies for controlling mosquito vectors. As technology in nanoparticles advances, zinc oxide (ZnO) nanoparticles have the potential as the alternative for chemical pesticides for mosquito larvicides due to their optical properties and widespread usage in different industries. The purpose of this study was to determine the toxicity of ZnO nanoparticles towards Ae. aegypti larvae and to examine the physiologies of Ae. aegypti mosquito larvae treated with ZnO nanoparticles at LC50 level. Toxicity bioassays were carried out to determine LC50 and LC90 values. The larvae surface and midgut treated with LC50 ZnO were examined using the Scanning Electron Microscope (FESEM) and Dispersive X-ray spectroscopy (EDX). The LC50 and LC90 concentrations of ZnO nanoparticles after 4 hr of direct UV exposure against Ae. aegypti larvae were 49.141 mg/L and 64.195 mg/L, respectively. After exposure to ZnO nanoparticles, Ae. aegypti larvae showed morphological abnormalities, including distorted and shrunk body parts as well as midgut rupture. Overall, the findings suggest that ZnO nanoparticles have the potential to replace chemical pesticides as a means of reducing the populations of Ae. aegypti mosquitoes.

Revisiting the paradigm of anhematophagy in male mosquitoes.

Female mosquitoes are reproductively obligate bloodfeeders which feed on vertebrate blood to obtain nutrients required for egg production (driving transmission of vector-borne pathogens in the process), and which rely on plant sugars for their non-reproductive energy requirements. Male mosquitoes, on the other hand, are thought to rely exclusively on plant sugars for their energetic needs; indeed, this dichotomy is one of the central tenets of medical entomology. Here, we show that male Culex tarsalis and Aedes aegypti mosquitoes will readily take blood from a membrane feeder when reared under dehydration conditions with no toxic effects. Mosquitoes with impaired humidity detection do not increase their bloodfeeding rates when dehydrated compared to wild-type controls. While conventionally reared males ignore a human host, dehydrated males are attracted to and attempt to probe, with some success, although they cannot access host capillaries. However, they will take blood from a vertebrate host wound. When fed a blood meal containing West Nile virus, male mosquitoes can become infected with and orally transmit the pathogen at rates and titers equivalent to females. Finally, vertebrate DNA, likely from blood, was detected in wild-caught specimens of male Culex quinquefasciatus mosquitoes from Texas. These data suggest that under some circumstances male mosquitoes may be able to probe and/or ingest blood and transmit pathogens to vertebrate hosts, and that their role in maintaining pathogen transmission cycles should be re-examined.

Comparative efficacy of Biogents Sentinel and CDC traps for Aedes and Culex mosquito surveillance in India

BackgroundMosquitoes (Diptera: Culicidae) are important arthropod vectors that are responsible for transmitting numerous pathogens of major diseases. Adult mosquito traps help in effective surveillance. In this study, we compared the efficacy of the Biogents® Sentinel (BGS) traps and CO2-baited CDC traps for adult mosquito collection within four sites in India.ResultsWe found that BGS traps collected significantly more Culex quinquefasciatus and Aedes aegypti mosquitoes (85.8% of the total catch) than CDC traps (14.9% of the total catch). We also conducted a follow-up experiment to study the effect of adding CO2 as bait along with the BG lure to determine if it increases the number of mosquitoes collected. The results showed that BGS traps with BG lure + CO2 collected significantly more mosquitoes (69.5% of the total catch) than BGS traps with BG lure only (30.5% of the total catch). Although BGS traps were developed for surveillance of Ae. albopictus (Skuse) and Ae. aegypti (L.), the traps collected more Cx. quinquefasciatus (Say.) than any other mosquito species.ConclusionBGS trap is an efficient surveillance tool, and it can be used as part of an integrated mosquito management program by public health officials in order to combat mosquito-borne diseases.

Blood-Feeding Patterns and Resting Behavior of Aedes aegypti from Three Health Districts of Ouagadougou City, Burkina Faso.

Recent dengue outbreaks have occurred in Ouagadougou and Bobo-Dioulasso, the two major cities of Burkina Faso. Dengue is a viral disease transmitted primarily by Aedes aegypti, a highly anthropophilic mosquito that thrives in human-transformed environments and breeds predominantly in artificial containers. In 2018, we investigated the resting and blood-feeding habits of Ae. aegypti in urban settings of Ouagadougou. In a 3-month cross-sectional study starting in August 2018, indoors and outdoors resting adult mosquitoes were collected using Prokopack aspirators in three health districts (HD). All mosquitoes were morphologically identified, and DNA was extracted from blood-fed Ae. aegypti females. A multiplex polymerase chain reaction with specific primers was used to identify the origin of the blood meal. A total of 4,256 adult Ae. aegypti mosquitoes, including 1,908 females, were collected. A preference for exophily was recorded in Bogodogo and Nongremassom, although an unexpectedly higher proportion of blood-fed females were found indoors than outdoors. Respectively, 96.09%, 91.03%, and 95.54% of the blood meals successfully analyzed in Baskuy, Bogodogo, and Nongremassom were from a single human host, with the remainder from domestic mammals as single or multiple hosts. Modeling total Ae. aegypti and blood-fed female counts showed that among other predictors, human density, outdoor environment, and house type affect their total densities. Our study revealed an exophilic tendency as well as a pronounced anthropophilic preference of Ae. aegypti adults, critical findings to consider when planning accurate entomological surveillance and effective interventions against Ae. aegypti in urban settings.

Computational identification of Vernonia cinerea-derived phytochemicals as potential inhibitors of nonstructural protein 1 (NSP1) in dengue virus serotype-2.

Dengue virus (DENV) infection, spread by Aedes aegypti mosquitoes, is a significant public health concern in tropical and subtropical regions. Among the four distinct serotypes of DENV (DENV-1 to DENV-4), DENV-2 is associated with the highest number of fatalities worldwide. However, there is no specific treatment available for dengue patients caused by DENV-2. This study aimed to identify inhibitory phytocompounds in silico in Vernonia cinerea (V. cinerea), a widely used traditional medicinal plant, for treating DENV-2 associated illnesses. The chemical structures of 17 compounds from V. cinerea were sourced from the Indian Medicinal Plants, Phytochemistry, and Therapeutics (IMPPAT) database. These compounds underwent geometry optimization, were screened against nonstructural protein 1 (NSP1) of DENV-2, and further validated through molecular dynamics simulations (MDS). Baicalein, an established drug against DENV-2, was used for validation in molecular screening, MDS, and MM-GBSA analyses. Among these compounds, Beta-amyrin, Beta-amyrin acetate, Chrysoeriol, Isoorientin, and Luteolin showed promising potential as inhibitors of the NSP1 of DENV-2, supported by the results of thermodynamic properties, molecular orbitals, electrostatic potentials, spectral data and molecular screening. Besides, these compounds adhered to the Lipinski's "rule of 5", showing no hepatotoxicity/cytotoxicity, with mixed mutagenicity, immunotoxicity, and carcinogenicity. Furthermore, final validation through MDS confirmed their potential, demonstrating stable tendencies with significant inhibitory activities against NSP1 of DENV-2 over the control drug Baicalein. Among the screened compounds, Chrysoeriol emerged as the most promising inhibitor of NSP1 of DENV-2, followed by Luteolin and Isoorientin. Taken together, our results suggest that Chrysoeriol is the best inhibitor of NSP1 of DENV-2, which could be evaluated as a therapeutic agent or a lead compound to treat and manage DENV-2 infections.

Seasonal insights for integrative mosquito management from multi-year baseline entomological data on Aedes aegypti in Lee County, Florida.

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.

Competition is the main factor, compared to non-lethal threat of predation, affecting life-history traits of Aedes aegypti (Diptera, Culicidae) mosquitoes.

Mosquito larvae coexist with different species of predators in small freshwater bodies. These environments can vary widely in terms of the amount of food and larval densities. Our objective was to understand the impacts of the non-lethal threat of predation, combined with competition effects on Aedes aegypti development and adult life cycle. We tested the effects of two types of non-lethal threat of predation, divided into nine combinations of larvae densities and resource availability on Ae. aegypti larvae. We measured their isolated and combined impacts on larval mortality rate, time to reach pupation, adult size, and lifespan. Real non-lethal threat of predation resulted in a higher larval mortality (71%), compromised the sizes of the individuals (-7%) and prolonged the lifespan (19%) compared to control. Simulated treatment, the anti-predation behaviors led to an increase in larval mortality (21%) compared to the control treatment. Accelerating the larva's development time (-14%) to escape from a dangerous environment severely compromised the size of the individuals (-23%) and increased adult life (10%). The scarcity of food resources, high levels of competition, and non-lethal threat of predation as well, are effective stressors for Ae. aegypti. We observed that resources (food and space) were more important than predation risk for the fitness of the survivors. However, these stressors, individually or combined, can result in high larvae mortality, altered larval development and pupation, affecting the emergence of the adults, with small sizes and altered lifespan, ultimately reducing the fitness of the individuals. © 2024 Society of Chemical Industry.