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Dengue fever, a mosquito-borne viral infection, poses a significant global health threat, and early diagnosis is crucial for effective disease management. Human infection typically occurs through infected Aedes mosquitoes, such as Aedes aegypti or Aedes albopictus. The disease spectrum ranges from asymptomatic infection and mild febrile illness (dengue fever) to more severe conditions, such as dengue hemorrhagic fever and dengue shock syndrome. Dengue fever is characterized by severe headache, high fever, skin rash, muscle and joint pain, nausea, and vomiting. Dengue hemorrhagic fever is marked by high fever, an enlarged liver, hemorrhagic phenomena, shock, and often cardiovascular disorders. Dengue fever is transmitted through urban (human transmission cycle) and sylvatic (animal transmission cycle) cycles. The demand for early detection of this virus has increased to control the spread of infectious diseases and protect humankind from its harmful effects. Various methods can be employed for the laboratory diagnosis of this virus to detect the virus itself, viral nucleic acids, antibodies, or antigens, or a combination of these approaches. Recently, biosensors have emerged as a potential tool for detecting and quantifying viruses, offering fast detection, relative cost-effectiveness, and high sensitivity and selectivity compared to conventional diagnostic methods such as immunological and molecular techniques. Most biosensors employ electrochemical detection techniques with transducers, owing to their easy construction, low cost, ease of use, and portability. [ABSTRACT FROM AUTHOR]

Dengue virus (DENV) poses a global health threat, affecting millions individuals annually with no specific therapy and limited vaccines. Mosquitoes, mainly Aedes aegypti and Aedes albopictus worldwide, transmit DENV through their saliva during blood meals. In this study, we aimed to understand how Aedes mosquito saliva modulate skin immune responses during DENV infection in individuals living in mosquito-endemic regions. To accomplish this, we dissociated skin cells from Cambodian volunteers and incubated them with salivary gland extract (SGE) from three different mosquito strains: Ae. aegypti USDA strain, Ae. aegypti and Ae. albopictus wild type (WT) in the presence/absence of DENV. We observed notable alterations in skin immune cell phenotypes subsequent to exposure to Aedes salivary gland extract (SGE). Specifically, exposure lead to an increase in the frequency of macrophages expressing chemokine receptor CCR2, and neutrophils expressing CD69. Additionally, we noted a substantial increase in the percentage of macrophages that became infected with DENV in the presence of Aedes SGE. Differences in cellular responses were observed when Aedes SGE of three distinct mosquito strains were compared. Our findings deepen the understanding of mosquito saliva's role in DENV infection and skin immune responses in individuals regularly exposed to mosquito bites. This study provides insights into skin immune cell dynamics that could guide strategies to mitigate DENV transmission and other arbovirus diseases. [ABSTRACT FROM AUTHOR]

Introduction: Dengue fever is hyperendemic in several Southeast and South Asian countries, including India, with all four serotypes (DENV 1-4) circulating at different periods and in different locations. Sustainable and improved virological and entomological surveillance is the only tool to prevent dengue and other vector-borne diseases. Objectives: The present study has been carried out to detect and characterize the circulating dengue virus (DENV) in field-collected Aedes mosquitoes in Bhopal, Central India. Methods: Aedes mosquitoes were collected from 29 localities within Bhopal city during October 2020 to September 2022. DENV infection was assessed in the individual head and thorax regions of Aedes mosquitoes using reverse transcriptase PCR. Positive samples were sequenced, and the circulating serotypes and genotypes were determined using phylogenetic analysis. Results: DENV RNA was detected in 7 Aedes aegypti and 1 Aedes albopictus, with infection rates of 0.59 and 0.14%, respectively. Phylogenetic analysis revealed all the isolates belonged to DENV serotype 2 and distinctly clustered with the non-Indian lineage (cosmopolitan genotype 4a), which was not recorded from the study area earlier. The time to most common recent ancestor (TMRCA) of these sequences was 7.4 years old, with the highest posterior density (HPD) of 3.5-12.2 years, indicating that this new lineage emerged during the year 2014. This is the first report on the DENV incrimination in both Ae. aegypti and Ae. albopictus mosquitoes collected from Bhopal, Central India. Conclusion: The observed emergence of the non-Indian lineage of DENV-2 in Bhopal, which again is a first report from the area, coincides with the gradual increase in DENV cases in Bhopal since 2014. This study emphasizes the importance of DENV surveillance and risk assessment in this strategically important part of the country to decipher its outbreak and severe diseasecausing potential. [ABSTRACT FROM AUTHOR]

Introduction: As strong wings are integral to the survival of a mosquito; our study examined the effects of different types of plant materials on the wing size and shape of Aedes aegypti mosquitoes. Methods: Thirty eggs were hatched in water containing three different doses of either dry grass, dry leaves, or dry twigs. Eleven landmarks were first identified on the wings of Aedes aegypti mosquitoes before the differences in wing shapes were observed using landmark data acquisition software programmes such as tpsDig version 1.40 and MorphoJ. Results: The wing size of adult Aedes aegypti mosquitoes that had been hatched in water containing dry grass was found to be larger than those hatched in water containing dry leaves or dry twigs. The wing centroid size of these mosquitoes was also the largest followed by mosquitoes that had been exposed to dry leaves and dry twigs. Therefore, introducing dry grass at the larval stage had the most significant impact on the wing size and shape of adult mosquitoes while higher doses of dry grass at the larval stage produced adult mosquitoes with larger wings than those exposed to dry leaves and twigs. Conclusion: Adult Aedes aegypti mosquitoes that were hatched in water containing higher doses of plant materials were found to have more separated wings. [ABSTRACT FROM AUTHOR]

This study reports the efficacy of I.M.O.S (Intelligent Mosquito System) by using Xmos mini aerosol in reducing Aedes mosquito population in 17th College, Universiti Putra Malaysia (UPM). Prior to the experiment, the Aedes mosquito population was determined in all blocks of the 17th College, UPM. The I.M.O.S. was installed above the entrance door of the hall and two rooms and was set to automatically spray at 6.30 am and 4.00 pm every day. No intervention was used in the control house. Adult efficacy study was conducted by placing 20 Aedes mosquitoes in each cage and was hung at a distance of 10 feet from the I.M.O.S. The mortality caused by I.M.O.S throughout the exposed two hours and after 24 hours of exposure was recorded. The number mosquito eggs population were calculated throughout the installation of I.M.O.S. Data were analysed using two-way ANOVA and paired T-test, respectively. The mean number of Aedes mosquito eggs and ovitraps index showed no significant difference (p>0.05) between control and treatment blocks. There were significant differences (p<0.05) in the percentage of knockdown of adult Aedes mosquitoes (10, 20, 30, 60 and 120 minutes after exposure) and the mortality of adult Aedes mosquitoes after 24 hours exposure. Nano and slow-release technology of the I.M.O.S with Xmos mini aerosol proved that this type of intervention can kill adult Aedes mosquitoes. Thus, it is a potential intervention for vector control and management. [ABSTRACT FROM AUTHOR]

Abstract Flavivirus causes arthropod-borne severe diseases that sometimes lead to the death. The Flavivirus species including Dengue virus, Zika virus and yellow fever virus are transmitted by the bite of Aede s mosquitoes. All these viral species target the people living in their respective endemic zone causing a high mortality rate. Recent studies show that immune factors present in the Ae. aegypti saliva is the hidden culprit promoting blood meal collection, suppressing host immune molecules and promoting disease establishment. This study was designed to develop a subunit vaccine using Aedes mosquito salivary proteins targeting the aforementioned Flaviviruses. Subunit vaccine was designed very precisely by combining the immunogenic B-cell epitope with CTL and HTL epitopes and also suitable adjuvant and linkers. Immunogenicity, allergenicity and physiochemical characterization were also performed for scientific validation. Molecular docking and molecular dynamics simulations studies were carried out to confirm the stable affinity between the vaccine protein (3D) and TLR3 receptor. At last, in silico cloning was executed to get the subunit vaccine restriction clone into pET28a vectro to express it in microbial expression system. Additionally, this study warrants the experimental evaluation for the validation purposes. Highlights • Immunoinformatics approach was used to yield a subunit vaccine construct targeting Aedes aegypti transmitted diseases. • This vaccine promises a unique constituents mainly B cell, CTL and HTL binding epitopes. • The Vaccine construct shows good antigenicity values. Thus, assuring activation of humoral as well as cell-mediated immunity. • The vaccine construct is non- allergenic which signifies very less side effect after administration. • This vaccine can be express using E. coli which shows its cost efficiency, if marketed in future. [ABSTRACT FROM AUTHOR]

Background & objectives: The quality of breeding sites is reflected through the pupal productivity and the life history traits of Aedes mosquitoes. Using nutrient reserves and pupal productivity of Aedes as indicators, the larval habitats including sewage drains were characterized to highlight the habitat expansion and vector management. Methods: The pupae and adults collected from the containers and sewage drains were characterized in terms of biomass and nutrient reserves and the data were subjected to three way factorial ANOVA. Discriminant function analyses were performed to highlight the differences among the habitats for sustenance of Aedes mosquitoes. Results: Survey of larval habitats from the study area revealed significant differences (P<0.05) in the pupal productivity of Aedes among the habitats and months. Despite sewage drains being comparatively less utilized for breeding, the pupae were of higher biomass with corresponding adults having longer wings in contrast to other habitats. The nutrient reserve of the adults emerging from pupae of sewage drains was significantly higher (P<0.05), compared to other habitats, as reflected through the discriminant function analysis. Interpretation & conclusions: The present results showed that for both Ae. aegypti and Ae. albopictus, sewage drains were equally congenial habitat as were plastic, porcelain and earthen habitats. Availability of Aedes immature in sewage drains poses increased risk of dengue, and thus vector control programme should consider inclusion of sewage drains as breeding habitat of dengue vector mosquitoes. [ABSTRACT FROM AUTHOR]

Essential oils have been widely used as an active ingredient in mosquito repellent products. However, essential oils are highly unstable and prone to degradation when exposed to the environment during storage. Microencapsulation techniques help to maintain the stability of molecules in essential oils that are sensitive to environmental stress, and therefore improve shelf life. In this study, the physical stability and efficacy of a repellent formulation consisting of encapsulated Citrus grandis essential oil (CGEO) were evaluated under different storage conditions over a 12-month period by comparing the formulation with a non-encapsulated formulation. The formulations were both stored under two different storage conditions, i.e., 25 ± 2 °C/60% ± 5% relative humidity (RH) and 40 ± 2 °C/75% RH ± 5%, for 12 months. Droplet size, zeta potential, and pH value were measured after 1, 6, and 12 months of storage to determine their stability. For the study of efficacy, each formulation was tested against Aedes aegypti under laboratory conditions. We found that the microencapsulated formulation's physical characteristics showed insignificant changes as compared with the non-encapsulated formulation during storage. The microencapsulated formulation demonstrated better repellent effects, sustaining high protection (>80%) for 4 more hours of exposure after 12 months of storage as compared with the non-encapsulated formulation that demonstrated high protection for only an hour post application. Microencapsulation helped to preserve the stability of the formulation, which resulted in high protection being maintained for over 12 months of storage. [ABSTRACT FROM AUTHOR]