Search Results (583)

Mosquito-borne diseases are an emerging public health challenge in Europe, driven by the spread of invasive mosquito species capable of sustaining outbreaks of tropical arboviral diseases. Rising temperatures, shifting precipitation patterns, human-driven habitat changes, and prolonged transmission seasons have increased the risk of dengue, chikungunya, and West Nile virus outbreaks, among other vector-borne diseases. Effective control requires a multifaceted approach, combining traditional and novel methods with advanced surveillance technologies and community involvement. However, growing insecticide resistance and concerns about insecticide use highlight the need for more prudent management of current tools and the development of innovative alternatives. Genetic control strategies, including the Sterile Insect Technique (SIT), Wolbachia-based approaches, and genetically modified (GM) mosquitoes, offer promising solutions but still face scientific, regulatory, and societal challenges. This review explores the current landscape of mosquito-borne disease control in Mediterranean Europe, emphasizing key challenges and emerging solutions. An integrated approach that strengthens surveillance, promotes sustainable control methods, and incorporates novel biotechnological tools supported by smart technologies will be essential to reduce the future burden of mosquito-borne diseases in the region. Full article

Dengue remains a significant health burden in Thailand, with over 160,000 cases reported in 2023. Although two dengue vaccines are approved, uptake remains limited. This study assessed Knowledge, Attitudes, and Practices (KAP) toward dengue and behavioural drivers of vaccine willingness using the Capability, Opportunity, Motivation–Behaviour (COM-B) framework, which posits that health behaviours arise from capability (knowledge/skills), opportunity (environmental/social enablers), and motivation (beliefs/drivers). A cross-sectional online survey was conducted in September 2024 among 600 Thai adults aged 20–60 years. The questionnaire, adapted from the GEMKAP study, generated composite KAP and COM-B scores (0–100%). Willingness to vaccinate was measured on a 0–10 Juster scale, with multivariable regression identifying behavioural predictors. Of 600 respondents, 40% were male, with a median age of 40 years, and 23% were in high-dengue-burden areas. Knowledge scores were moderate (51%), and dengue prevention practices were low (40%). The proportion of respondents with high willingness to vaccinate (score 8–10) was 68%, which was positively associated with Reflective Motivation and Physical Opportunity. Hesitancy centred on vaccine side effects (29%) and cost concerns (13%). These findings suggest that despite generally favourable attitudes, vaccine uptake is hindered by safety, cost, and awareness gaps. Physician communication and the integration of vaccines into schools, workplaces, and primary care, along with education and vector control, are key for sustainable national coverage. Full article

Dengue remains a public health concern in Singapore, with endemic transmission and recurring outbreaks. This study presents results from a Singapore-focused subgroup of the Growth and Emerging Markets Knowledge, Attitudes, and Practices (GEMKAP) cross-sectional survey, which assessed public Knowledge, Attitudes, and Practices (KAP) levels related to dengue and prevention. A total of 400 adult respondents from Singapore participated in an online survey conducted between September and October 2022. Overall KAP scores were 48% (Knowledge), 61% (Attitudes), and 36% (Practices). Awareness of dengue transmission was widespread (96% identified mosquitoes as the vector and 97% recognised stagnant water breeding), while fewer respondents recognised the availability of a dengue vaccine (23%) or the absence of a medicinal cure (38%). Trust in the government’s dengue control efforts was high, though respondents practised an average of 5.1 out of 10 recommended prevention measures. Of the respondents, 25% had a high willingness to vaccinate against dengue. Multivariate analysis revealed that positive vaccine perceptions, past dengue experience, automatic motivation, and social opportunity were associated with willingness to vaccinate. Respondents supported a multi-pronged dengue management approach combining education, vector control, and vaccination. Future efforts should integrate behaviour change strategies, enhance multi-stakeholder collaboration, and empower communities to ensure sustainable impact. Full article

West Nile virus (WNV) is a mosquito-borne flavivirus with one of the widest global distributions. Since its discovery in Uganda in 1937, it has become a major zoonotic pathogen, and after its introduction into the United States in 1999, it spread rapidly across the Americas, becoming the leading cause of neuroinvasive arboviral disease. Its expansion illustrates a remarkable ecological adaptability, further intensified by climate change. In Latin America and the Caribbean, WNV circulation has been consistently documented in birds, horses, and mosquitoes; however, confirmed human cases remain disproportionately scarce compared with North America and Europe. Reports include sporadic human cases in Brazil (>100 since 2014), Mexico (~13), Argentina (2006–2007), Puerto Rico (2007), Nicaragua, and Haiti, while animal and vector evidence extends to Guatemala, El Salvador, Belize, Costa Rica, Bolivia, Paraguay, Colombia, Venezuela, Cuba, and Ecuador. This paradox likely reflects structural limitations within regional health systems, including underdiagnosis, restricted diagnostic capacity, and significant surveillance gaps, particularly in contexts where mild febrile syndromes may be misclassified as dengue, Zika, or Chikungunya. The regional risk of emergence is further amplified by climatic variability, ecological change, and intensifying human–wildlife interactions. Experiences from Europe highlight the importance of early detection, transfusion safety, and integrated surveillance within a One Health framework. Strengthening preparedness in Latin America will require investments in diagnostic infrastructure, implementation of standardized seroepidemiological surveys, development of predictive models tailored to local ecological contexts, and robust intersectoral collaboration. Full article

Dengue virus (DENV) is a major public health concern in tropical and subtropical regions, including the Pacific. Temperature is recognised as a major driver of transmission under climate change. Understanding how higher temperatures may alter DENV transmission is essential to anticipate future dengue risk. Therefore, we assessed the effect of temperature on DENV-1 in Aedes aegypti from New Caledonia. Mosquitoes were orally infected and maintained for 14 days at 26.6 °C (average temperatures during recent outbreaks) or 31.1 °C (SSP5-8.5 scenario projected temperatures). Mosquito bodies, heads, and saliva were analysed separately to determine infection, dissemination, and transmission rates as well as transmission efficiencies. Infectious virus was detected by using a fluorescent focus assay, and viral titres were quantified via TCID₅₀ assays. No significant differences were observed in infection, dissemination, and transmission rates or transmission efficiencies between the two temperatures. However, DENV titres in mosquito bodies and heads were significantly higher at 31.1 °C than 26.6 °C. Our results indicate that elevated temperature increases viral loads within the insect but not the proportion of infectious mosquitoes, highlighting the importance of considering temperature as a key parameter in assessing dengue risk under climate change. Further studies are needed to investigate the effects of temperature on virus–mosquito interactions. Full article

Background: Dengue infection (DI) is a mosquito-borne arboviral disease primarily transmitted by infected female Aedes mosquitoes. In Bangladesh, DI poses a substantial public health challenge with recurrent outbreaks and rising incidence rates. This systematic review assesses the epidemiological characteristics of dengue infection in Bangladesh, focusing on demographic, clinical, and geographic trends. Objectives: To analyze dengue prevalence, demographic distribution, clinical symptoms, and serotype patterns in Bangladesh, with an emphasis on urban–rural disparities, gender differences, and serotype evolution. Methods: A systematic search was conducted across PubMed, Scopus, Web of Science, and Global Health (Ovid) databases, reviewing studies published from 2000 to 2024. Following PRISMA guidelines, 25 studies meeting eligibility criteria were selected. Data extraction and quality assessment were independently performed by three reviewers, ensuring methodological rigor. Results: Dengue incidence was higher in urban areas, mainly affecting males aged 20–34, with dengue virus serotype 3 (DENV-3) as the dominant serotype. Fever, headache, and joint pain were the most common symptoms, while severe cases often presented with respiratory and hemorrhagic complications. Acute symptoms like dyspnea and dehydration spread rapidly in densely populated areas. In rural areas, dengue showed a more endemic pattern, with persistent symptoms such as gastroenteritis and muscle pain. Conclusion: Dengue is now firmly endemic in Bangladesh, with clear geographic, demographic, and clinical differences. The dominance of DENV-3 and its association with more severe illness highlight the need for targeted and context specific interventions. Control efforts should prioritize vector management, public education, and continuous surveillance in urban areas, while strengthening community surveillance and primary healthcare in rural settings. Further research on rural transmission and the clinical impact of DENV-3 is essential to guide effective and tailored dengue control strategies. 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

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

Background/Objectives: Arboviral diseases share common vectors, geographic distribution, and symptoms. Developing Machine Learning diagnostic tools for co-circulating arboviral diseases faces data-scarcity challenges. This study aimed to demonstrate that proof of concept using synthetic data can establish computational feasibility and guide future real-world validation efforts. Methods: We assembled a synthetic dataset of 28,000 records, with 7000 for each disease—Dengue, Zika, and Chikungunya—plus Influenza as a negative control. These records were obtained from the existing literature. A binary matrix with 67 symptoms was created for detailed statistical analysis using Odds Ratios, Chi-Square, and symptom-specific conditional prevalence to validate the clinical relevance of the simulated data. This dataset was used to train and evaluate various algorithms, including Multi-Layer Perceptron (MLP), Narrow Neural Network (NN), Quadratic Support Vector Machine (QSVM), and Bagged Tree (BT), employing multiple performance metrics: accuracy, precision, sensitivity, specificity, F1-score, AUC-ROC, and Cohen’s kappa coefficient. Results: The dataset aligns with the PAHO guidelines. Similar findings are observed in other arboviral databases, confirming the validity of the synthetic dataset. A notable performance across all evaluated metrics was observed. The NN model achieved an overall accuracy of 0.92 and an AUC above 0.98, with precision, sensitivity, and specificity values exceeding 0.85, and an average Uniform Cohen’s Kappa of 0.89, highlighting its ability to reliably distinguish between Dengue and Influenza, with a slight decrease between Zika and Chikungunya. Conclusions: These models could accelerate early diagnosis of arboviral diseases by leveraging encoded symptom features for Machine Learning and Deep Learning approaches, serving as a support tool in regions with limited healthcare access without replacing clinical medical expertise. 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

Arboviral diseases are emerging public health challenges in Burkina Faso, largely driven by the proliferation of Aedes aegypti mosquitoes in the environment. Effective surveillance of arbovirus circulation is critical to inform interventions. From August 2022 to June 2023, we implemented a comprehensive entomological surveillance platform in five sectors of Bobo-Dioulasso. Surveillance methods included oviposition traps to collect eggs, larval surveys in some concessions per sector conducted bimonthly, and adult mosquito collections using BG-Sentinel traps and Prokopack aspirators. Mosquito samples colonized by Ae. aegypti were identified morphologically, confirmed by conventional PCR, and screened by RT-PCR for dengue (DENV), chikungunya (CHIKV), yellow fever (YFV), and Zika (ZIKV) viruses. Molecular analysis detected dengue virus and yellow fever virus in mosquito pools from sector 22 and chikungunya virus in sectors 9 and 26; no Zika virus was found. This study demonstrates the successful establishment of an integrated entomological surveillance platform capable of capturing the spatial and temporal dynamics of arboviral vectors and virus circulation in Bobo-Dioulasso. The identification of active dengue and chikungunya transmission underlines the urgent need for sustained vector monitoring and targeted control strategies. Our approach provides a scalable model for arboviral disease surveillance and epidemic preparedness in West African urban settings. Full article

Arthropod-borne orthoflaviviruses, including dengue, Zika, Japanese encephalitis, yellow fever and West Nile viruses, pose a significant global public health threat, causing hundreds of millions of infections annually with severe clinical symptoms. However, the lack of effective vaccines and antiviral drugs, coupled with the biosafety risks associated with handling live highly pathogenic strains, hinders progress in antiviral research. Pseudovirus technology, which uses single-round infectious viral particles lacking replication competence, has thus gained prominence as a safe and versatile tool for antiviral research. This review systematically summarizes the construction, optimization, and applications of orthoflavivirus pseudoviruses in antiviral research. The primary construction strategies of orthoflavivirus pseudoviruses rely on multi-plasmid co-transfection of viral replicons and structural protein expression vectors, leveraging the host cell secretory pathway to mimic natural viral assembly and maturation. The core applications of pseudovirus technology are highlighted, including high-throughput screening and detection of neutralizing antibodies, identification of antiviral drugs targeting viral entry or replication, and evaluation of vaccine immunogenicity. Despite these strengths, the approach still faces limitations, such as incomplete simulation of native viral structures and batch-to-batch titer variability, which may affect the physiological relevance of findings. In summary, orthoflavivirus pseudovirus technology has become an essential platform in both basic virology research and translational medicine, providing critical insights and tools in the ongoing fight against arthropod-borne orthoflaviviruses diseases. 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

Vector-borne diseases are strongly influenced by climate, yet the magnitude and temporal variability of climate–disease relationships remain poorly quantified. Outbreaks occur abruptly, and responses are typically delayed, underscoring the need for predictive tools that can support proactive interventions. This study applies Temporal Fusion Transformers (TFTs) to long-term, high-resolution climate datasets and to weekly malaria and dengue case records from South Africa and Vietnam to assess predictive performance and identify key environmental drivers. The models incorporated diverse climatic predictors and large-scale climate indices and were trained using multi-horizon forecasting with novel loss functions and physics-based constraints. The best malaria model achieved an R² of 0.95 and an MAE of 4.98, while leading dengue models reached R² values up to 0.90. Variable-importance analyses derived from model-learned weights showed that extreme temperature and rainfall metrics were consistently the strongest predictors, with ENSO (El Niño Southern Oscillation) and IOD (Indian Ocean Dipole) improving longer-range malaria forecasts. Furthermore, climate–disease risk dynamics were explored, revealing specific temperature and rainfall thresholds associated with elevated transmission and highlighting non-stationary relationships across decades. These findings demonstrate accurate, interpretable forecasting offered by TFTs and represent a valuable tool for early warning and understanding of complex climate–disease interactions. Full article