Search Results (445)

Aedes mosquitoes are among the most important vectors of arboviral diseases such as dengue, Zika, and chikungunya. Mapping their geographic and temporal patterns is essential for understanding disease risk and guiding vector control. This systematic review provides an updated synthesis of the spatial and temporal distribution of Aedes species across Iran. A comprehensive search of international (PubMed, Scopus, Web of Science) and national (SID, IranMedex, Magiran) databases was performed for studies published between 1980 and 2025. Eligible publications reporting the occurrence or distribution of Aedes mosquitoes were screened according to PRISMA guidelines. Data were extracted and analyzed descriptively to identify long-term spatial and temporal trends. Sixty-six studies met the inclusion criteria, covering more than 20 provinces and examining over 390,000 mosquito specimens. Aedes caspius was the dominant species nationwide, reflecting its high ecological adaptability. Invasive vectors, Ae. aegypti and Ae. albopictus, were recorded mainly in southern coastal provinces and, more recently, in the humid northern regions. Over time, surveys have evolved from scattered faunistic reports to systematic nationwide monitoring, revealing clear patterns of ecological expansion driven by climatic and environmental factors. Increasing reports, broader geographic distribution, and adaptability to diverse ecological settings indicate an ongoing expansion of Aedes mosquitoes in Iran. While these developments reflect successful entomological surveillance and public health efforts, enhanced preparedness and continuous monitoring are essential to manage potential Aedes-borne outbreaks effectively. Full article

Dirofilaria repens is the leading cause of subcutaneous (dogs) and subcutaneous/ocular dirofilariosis (humans) in the Old World. Despite its rapid geographical spread, driven by climate change, the emergence of new invasive vectors (Aedes albopictus) and growing interest in its study due to the emergence of new cases in areas previously free of the parasite, amongst other factors, scientific research into this pathogen remains limited. This study provides the first longitudinal bibliometric analysis of global research on D. repens (1955–2025). Data from Web of Science and Scopus were processed using PRISMA and RAMIBS protocols, resulting in a normalized corpus of 624 documents analyzed via science mapping techniques. The field exhibits a sustained annual growth rate of 3.79%, transitioning into an exponential expansion phase in 2011. While Italy retains historical leadership, spatial analysis confirms a research displacement towards Central and Eastern Europe (Germany, Poland). Thematic evolution reveals a structural shift from isolated clinical case reports to a multidisciplinary ecosystem dominated by molecular epidemiology, vector competence, and surveillance. Dirofilaria repens has gone from being a minor and neglected issue to having a significant number of reports and studies subject to interest in addressing the disease that results from its infection in different hosts. However, the intellectual structure exposes an operational fragmentation between clinical medicine and medical entomology. Future research must overcome national silos and integrate reservoir management with vector control, transforming the current reactive approach into a predictive preventive system aligned with the One Health framework. Full article

Dengue fever (DF) is an acute mosquito-borne infectious disease caused by dengue virus (DENV), primarily transmitted by Aedes aegypti and Aedes albopictus. Nearly 4 billion people worldwide are at risk of infection, and the 2024 epidemic reached an unprecedented scale. Severe cases can lead to hemorrhage, shock, and even death, prompting the WHO to classify it as a potential pandemic pathogen. Current prevention and control measures face prominent bottlenecks, including limited applicable populations for vaccines, lack of specific antiviral drugs, and increasing insecticide resistance in mosquito vectors. Notably, susceptible animal models serve as core tools for elucidating the pathogenic mechanisms of dengue virus, screening antiviral drugs, and evaluating vaccine protective efficacy, holding irreplaceable significance. This review systematically summarizes the characteristics, application scenarios, and research progress of mainstream and potential susceptible animal models, including non-human primates, mice, pigs, tree shrews, and bats. It covers model systems with different immune statuses, genetically modified types, and species-specific traits. Among these, mouse models are the most widely used due to their high flexibility and controllable cost, while non-human primate models have become key carriers for preclinical vaccine evaluation by virtue of their high homology with human immune responses. However, current models generally suffer from core bottlenecks, such as incomplete simulation of core severe phenotypes, insufficient restoration of immune mechanisms, unclear viral receptor mechanisms, and lack of unified standards for inoculation doses and evaluation indicators. These limitations make it difficult to accurately replicate key severe disease mechanisms, including antibody-dependent enhancement (ADE) and cytokine storms. Future model development should focus on core requirements—including intact immunity, broad-spectrum susceptibility, and accurate simulation of clinical pathological features—prioritize solving the simulation challenges of ADE and cytokine storms, and establish standardized experimental systems and evaluation criteria. By comprehensively summarizing the advantages and limitations of the existing models, this review provides a systematic reference for the optimization and upgrading of dengue virus-susceptible animal models. It also holds important guiding significance for promoting the in-depth development of basic dengue research, innovation in prevention and control technologies, and clinical transformation and application. Full article

The overuse of chemical insecticides highlights the urgent need for novel vector control strategies. Insect-specific viruses (ISVs), such as the cell-fusing agent virus (CFAV), have shown potential to block arbovirus transmission by inhibiting viral replication in mosquitoes. However, the effects of CFAV beyond its natural host, Aedes aegypti, remain largely unexplored. In this study, we established a CFAV infection model in Aedes albopictus, a major vector for Zika virus (ZIKV), via intrathoracic injection. Stable infection was achieved, with viral loads reaching up to 10⁷ copies per mosquito by day 10 post-injection. Nevertheless, high post-injection mortality (median survival: 3 days) was observed, which we attribute primarily to mechanical injury. No evidence of vertical transmission of CFAV was detected in Ae. albopictus. Co-injection of CFAV and ZIKV did not significantly affect ZIKV replication in this species. In contrast, in Ae. aegypti pre-infected with CFAV followed by oral ZIKV challenge, CFAV significantly reduced ZIKV infection rates in the ovaries at day 4 and viral loads in salivary glands at day 10. These findings demonstrate that while CFAV can productively infect Ae. albopictus, it does not undergo vertical transmission in this species, and has no inhibitory effect on ZIKV under the co-infection conditions tested. This study underscores challenges associated with using single ISVs such as CFAV for arbovirus control and highlights the complex, bidirectional role of multiple ISV co-infections. While exploring multi-ISV combinations may offer a potential strategy to enhance antiviral efficacy, their net effect—whether suppression or enhancement of arboviruses—warrants careful investigation. Full article

Mosquitoes are key vectors of numerous infectious diseases, making the study of their behavior essential for effective control strategies. This study investigates the color preferences of Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus during foraging, using an ink-based staining method to assess feeding behavior under varying light intensities (0, 130 and 1600 lx). At 0 lx, no consistent visual preferences emerged, confirming reliance on olfactory cues only. Under dusk-like illumination (130 lx), diurnal Aedes exhibited a tendency to approach red stimuli (probably perceived as grey) over darker targets, with Ae. albopictus females and males showing significant preference for red over green responses, indicating early salience of red contrasts. At high illumination (1600 lx), Aedes shifted preference toward black, especially in males, reflecting dominance of achromatic contrast and camouflage considerations. In contrast, crepuscular Cx. quinquefasciatus showed strong attraction to black at dusk-like light in both sexes; at high illumination, females’ preferences shifted from black to red, whereas males maintained or reverted to black preference across assays. These divergent patterns align with differences in photoreceptor sensitivity, contrast processing, and ecological niches governing host- and swarm-seeking. Identifying how dusk-like versus bright light modulates color-driven behavior provides insights for designing trap colors and illumination regimes optimized for specific mosquito species and sexes, thereby enhancing targeted vector-control strategies. Full article

Aedes albopictus is an important vector of several arboviruses and has expanded its distribution throughout Latin America and the Caribbean in recent decades. Despite its increasing epidemiological relevance, data on insecticide resistance in this region remain limited compared to Aedes aegypti. This review compiled and analyzed the published evidence on this topic across the region. A literature search was conducted in PubMed, SciELO, Google Scholar, LILACS, and DOAJ, using combinations of the terms “insecticide resistance” or “insecticide susceptibility” plus “Aedes albopictus”, and the names of all countries recognized by the United Nations as part of the region. Studies published until May 2025 were considered, regardless of the publication year. Following the core PRISMA principles adapted for this review, 33 studies were identified, of which 17 met the inclusion criteria. Results indicate recurrent but uneven reports of resistance, with organophosphates being the most frequently evaluated insecticide (33.9%), followed by pyrethroids (27.7%) and carbamates (10.8%), and metabolic mechanisms being the most implicated. Evidence suggests that control actions focused on Ae. aegypti may also impose selective pressure over Ae. albopictus. Overall, the resistance found on Ae. albopictus emphasizes the need for expanded and standardized surveillance to support effective vector control across the Americas. Full article

Understanding the intrinsic potential of persistent dengue virus (DENV) replication and survival in vector host cells is critically important. In this study, we investigated to what extent DENV can replicate within the vector host Aedes albopictus C6/36 mosquito cells (cell line routinely used for propagation of DENV in research laboratories). We detected DENV serotype 2 (DENV2) loads in cell culture supernatants collected at different days post infection (3, 19, 33, 60, 90, 120 and 175) and found the presence of capsid transcripts and protein levels in these virus supernatants. Tissue culture infectious dose 50 (TCID50) assay revealed a gradual reduction in viral titers and infectivity from days 19 to 175 post DENV2 infection. Furthermore, infection kinetics with these virus supernatants collected at different days post DENV2 infection demonstrated declining viral replication in naïve C6/36 cells and human endothelial recipient cells. These results provided information on viral replication competence and the persistency of DENV2 infection from days 19 to 175 in mosquito cells. Extracellular vesicles (EVs) isolated from DENV2-infected C6/36 cell culture supernatants showed a progressive increase in EV concentration from day 33 to day 175. While DENV2 loads within these EVs declined over time, their ability to mediate infection in naïve C6/36 and endothelial cells remained constant. Notably, the viral membrane (M) protein was detected in EVs at days 3, 19, and 33 but was absent at later timepoints (days 60, 90, 120, and 175). The prM protein was not detected in any of the samples analyzed. In conclusion, DENV2 exhibits the capacity for persistent infection in mosquito cells, thereby potentially serving as a model for investigating the mechanisms that govern years of long-term and sustained viral infections within the vector host. Full article

The Incompatible Insect Technique (IIT) is a species-specific, eco-friendly mosquito control method that relies on releasing Wolbachia-infected males, which induce cytoplasmic incompatibility (CI), rendering eggs inviable when mating with wild females. Aiming at optimizing IIT protocols in terms of cost-effectiveness, data on incompatible male dispersal and survival and the distance- and time-related impact of induced sterility are fundamental. This study plans to fill this gap and reports findings from a two-year field trial (2022–2023) at the ENEA-Casaccia Research Center, based on single-spot releases of incompatible Aedes albopictus males (ARwP strain). Male releases were carried out in late September 2022 (~15,000 released males) and the early Ae. albopictus season (at the end of June 2023; ~24,000 released males). Fifty-eight ovitraps were located at a 20–900 m distance from the ARwP release spot and were monitored weekly from May to November to assess egg hatching rates and measure CI effects in relation to both distance and time. Following the 2023 release, samples of adults were collected at increasing distances from the release site and at multiple post-release time points to assess, individually, wild female fertility and ARwP male dispersal and survival using Wolbachia as a genetic marker. Statistical analyses revealed that: (a) the highest reduction in the egg hatching was found within 100 m from the release spot (46.5% and 19.9%, respectively, in 2022 and 2023) but remained significant even at greater distances (29.9% and 7.7% at 300 m, respectively, in 2022 and 2023); (b) accordingly, the highest reduction in the wild female fertility occurred within 100 m from the release spot (47.3%), but similar effects were recognizable up to 600 m; (c) the overflooding ratio of the ARwP males did not significantly differ between 3 and 11 days after the release, with ARwP males remaining active up to 18 days and dispersing as far as 400 m. These results demonstrate the potential of localized, non-inundative IIT trials to furnish clues for the setup of spatially optimized release strategies, especially in scaled-up applications. The study also emphasizes the need for standardized assessment tools and further research regarding environmental and behavioral factors influencing long-term suppression outcomes. Full article

Dengue is the most concerning mosquito-borne neglected tropical disease globally. The disease is caused by the dengue virus (DENV) and transmitted by the vector mosquito species belonging to the genus Aedes Meigen, 1818, particularly Aedes aegypti (Linnaeus, 1762) and Aedes albopictus (Skuse, 1895). In 2024, global cases of dengue exceeded 7.6 million, with India reporting 233,519 cases. These statistics underscore the ongoing challenge of managing dengue outbreaks worldwide. For generations, tribal communities across India have employed medicinal plant-based extracts as mosquito and other insect repellents. Plant-based phytochemicals are largely preferred over synthetic insecticides due to their perceived safety, non-toxicity to non-target organisms, and environmental sustainability. This review provides a comprehensive overview of various phytochemicals extracted from Indian medicinal plants for their larvicidal activity against Aedes mosquitoes. Furthermore, the article also reviews the mode of action of these phytochemicals, including neurotoxicity, mitochondrial dysfunction, sterol carrier protein-2 inhibition, midgut cytotoxicity, insect growth regulation disruption, and antifeedant activity, which aids in formulating dengue vector control strategies. Based on this review, Ecbolin B from Ecbolium viride, Alizarin from Rubia cordifolia, and Azadirachtin from Azadirachta indica exhibited better larval mortality rates against Ae. aegypti, with LC50 values recorded at 0.70, 1.31, and 1.7 ppm, respectively. Full article

Mosquito-borne diseases, including dengue fever, chikungunya, and Zika, continue to pose a substantial global public health challenge. This is largely attributable to the absence of effective vaccines and the expanding distribution of vectors such as Aedes albopictus (Ae. albopictus). Repellents, therefore, remain a critical component of prevention strategies for disease prevention. However, existing formulations have notable limitations. Synthetic repellents such as DEET provide broad-spectrum efficacy but may raise safety concerns, especially at high concentrations. In contrast, botanical repellents, such as citronella and camphor oils, offer more favorable safety profiles but are restricted by short protection durations due to their high volatility. To overcome these drawbacks, this research developed a composite mosquito repellent through the strategic combination of DEET (5–15%), citronella oil (10–20%), and camphor oil (5–15%). This formulation leverages interactions across multiple olfactory pathways to simultaneously enhance efficacy and reduce the DEET concentration. Orthogonal experimental optimization identified an optimized formulation, Mix-3 (consisting of 15% DEET, 15% citronella oil, and 10% camphor oil in 75% ethanol), which achieved a mean complete protection time of 9.45 h. Mix-3 provided longer protection than 7% DEET (mean difference = 5.50 h, p < 0.001), 4.5% IR3535 (2.83 h, p < 0.001), 10% citronella oil (3.58 h, p < 0.001), and 15% DEET (6.50 h, p < 0.001). Catnip oil did not contribute significantly to repellency (p = 0.895). This study demonstrates that the rational combination of synthetic and botanical repellents effectively overcomes the limitations of single-agent formulations, providing a long-lasting and scalable approach for vector control. Full article

The Asian tiger mosquito (Aedes albopictus) is an important vector of arboviruses, including dengue, chikungunya, and Zika. Its rapid global expansion has been facilitated by climate change and human activities. Phylogenetic studies of Ae. albopictus have largely relied on mitochondrial cytochrome c oxidase subunit 1 (COX1) and NADH dehydrogenase subunit 5 (ND5) markers, while the utility of cytochrome b (CYTB) remains underexplored. We collected Ae. albopictus from 13 sites in seven provinces of South Korea and analyzed COX1, ND5, and CYTB sequences. Genetic diversity indices were calculated, and phylogenetic relationships were reconstructed using maximum-likelihood trees and haplotype networks with a dataset obtained from GenBank. COX1 revealed 46 haplotypes, including six novel variants, with the highest diversity in southern coastal regions such as Busan and Suncheon. ND5 showed limited variation, with only two haplotypes. CYTB revealed three haplotypes, including region-specific variants in Busan and Wonju, supporting its role as a complementary marker. The Busan haplotype H41 bridged domestic and international lineages, suggesting Busan as a likely entry point. This study demonstrates that integrating COX1, ND5, and CYTB improves the resolution of Ae. albopictus phylogeography in Korea and highlights the need for continued molecular surveillance to guide vector control strategies. Full article

Arthropod-borne viruses (arboviruses) such as dengue, chikungunya, Zika, and yellow fever pose significant global health risks, with mosquitoes from the Aedes genus as the primary vectors responsible for human transmission. The Republic of the Marshall Islands (RMI), particularly the urbanized areas of Kwajalein and Majuro atolls, has experienced multiple outbreaks of dengue, Zika, and chikungunya with substantial health and economic impacts. Vector control remains the most effective method for reducing disease risk, but comprehensive data on local mosquito vector composition, distribution, and abundance are needed to guide new, effective control efforts. From 2022 to 2024, we conducted a longitudinal baseline assessment of mosquito abundance and species composition on Ebeye and nearby islets in Kwajalein Atoll, RMI, using BG-Sentinel traps and ovitraps. Aedes aegypti was the most prevalent species, accounting for 58% of all adult females collected across study locations, with higher relative abundances on Ebeye than on northern islets (4.7 vs. 2.3 per trap/night). Aedes albopictus was more abundant on northern islets (0.7 vs. 3.2 per trap/night), and Culex quinquefasciatus showed similar abundances (1.2 vs. 1.7 per trap/night). Rainfall and anthropogenic factors, including water storage practices and housing density, influenced mosquito abundance. These findings provide multi-seasonal baseline data to support targeted vector control strategies in RMI. Full article

The mosquito fauna was examined at the Mérida Zoological Park, a public site that is highly frequented and is a significant tourist attraction in the Yucatán Peninsula, in southeastern México. Between January 2023 and February 2024, 24 visits were made to the zoo to capture adult and immature stages of mosquitoes. Overall, 12 species belonging to five genera (Aedes, Anopheles, Culex, Ochlerotatus, and Uranotaenia) were documented. A total of 6601 adult mosquitoes of 10 species were captured by aspiration. The adult population of Culex quinquefasciatus Say was the most abundant, accounting for 80.84% (n = 5336) of the collection, while Aedes aegypti Linnaeus represented 11.53% (n = 761). The aviary was the site with the highest capture abundance (n = 2414) and species richness (n = 10). Aedes aegypti was abundant in the zoo restroom (n = 331) and had a higher proportion of blood-feeding females. A total of 1090 larvae and 160 pupae of nine species were collected from 26 mosquito breeding sites, accounting for 25% of positive containers (26/104). Aedes albopictus was frequently found in the larval stage (n = 43) compared to the adult stage (n = 3). The presence of mosquitoes with the potential to transmit pathogens poses a public health risk to zoo visitors and staff. Full article

La Crosse virus (LACV) is a mosquito-borne virus (family Peribunyaviridae) that can result in severe human infection in children under sixteen. Historically, LACV comprised two lineages, predominantly in the Midwest and Appalachian regions of the US. In 2005, a virus of a third lineage was detected in the Northeast; however, this and subsequently isolated strains of lineage III have not, to date, been implicated in human disease. One hypothesis for this discrepancy is that vector mosquitoes have a reduced vector competency for LACV lineage III, thus preventing horizontal transmission and clinical cases. Here, we utilized two mosquito species, Aedes triseriatus, the native vector, and Aedes albopictus, an invasive potential vector, each from both a historic LACV range (Virginia) and from the region of lineage III (Connecticut). Utilizing oral feeding and intrathoracic inoculation methods of viral exposure, rates of LACV infection, dissemination, and transmission (proxied via salivary secretion) and capability for vertical transmission (proxied via virus-positive ovaries) were determined by harvesting mosquito bodies, legs, saliva, and ovaries, respectively. Overall, we did not detect consistent differences in transmission between any lineage, species, or state of origin, at day 14 post-infection. However, we highlight the transmission potential of LACV lineage III in all mosquito populations tested here, representing the first evidence of lineage III competency in Aedes triseriatus and Aedes albopictus, indicating the potential for human disease. We thus suggest that the absence of human cases of LACV lineage III is not modulated by a lack of vector competency in mosquitoes. Full article

Insecticide resistance is increasing globally, and tools must be developed to combat this issue facing mosquito control programs that protect public health and inform operational decisions. Field trials to assess insecticide formulated products (FPs) are logistically demanding and weather-dependent and the Centers for Disease Control and Prevention bottle bioassays are optimized to test technical active ingredient (AI) residue, not aerosolized FP. Here, the methodological gap between AI and FP efficacy testing is addressed. The current study assessed the knockdown/mortality of laboratory and wild populations of Aedes albopictus and Culex pipiens/quinquefasciatus to four FPs (Biomist^®, Duet^®, AquaDuet^®, ReMoa Tri^®) in wind tunnel experiments. The number of FP droplets on mosquitoes was analyzed. Regression analyses showed that droplet counts on mosquitoes were significantly (p < 0.05) related to mosquito mortality for some FPs. The wild Culex population was resistant to all FPs in the wind tunnel. Here, when wind tunnel experiments resulted in a relatively low mortality rate (<90%), this indicates mosquito resistance to the FP. In these situations, a field trial would likely not achieve good results and may not be necessary. Alternatively, when wind tunnel experiments resulted in a nearly perfect mortality rate, a confirmatory field trial could be conducted, if needed. Full article