Search Results (222)

Dengue virus infection is a febrile illness caused by the Orthoflavivirus Dengue, which is transmitted by the mosquitoes Aedes aegypti or Aedes albopictus. Despite the fact that Dengue virus (DENV) is present in tropical and subtropical areas, climate change with global warming has been associated with the spread of Aedes aegypti and Aedes albopictus mosquitoes in several other regions worldwide. Notably, as the presence of Aedes albopictus has been confirmed in Southern Europe, already locally transmitted cases of Dengue virus infection have been reported in Europe. Apart from Europe, Australia has reported DENV cases in the 21st century that have been associated with the transmission of Aedes aegypti in the neighboring islands. Climate change, namely increasing temperatures, higher humidity and rainfalls, together with the development of urban heat islands, uncontrollable deforestation and urbanization, travelling and trade, has contributed significantly to the spread of DENV infection. Modern diagnosis based upon the advent of “multi-omics” techniques and machinery learning programs will be of the utmost importance for the early and accurate diagnosis of DENV infection. Finally, preventive measures for controlling Dengue virus infection, such as the use of repellents, educational programs, and improvement in water storage and waste management at the community levels would be very useful. Regarding climate change, the One Health Approach by integrating collaboration of various sectors and raising public awareness seems to be of the utmost importance in this context. Further investigations regarding the development of antiviral agents and vaccines will be an important asset in our armamentarium against DENV infection. Full article

Arboviral diseases are emerging as important public health threats in Saudi Arabia, driven by rapid urbanization, climate variability, the expansion of Aedes aegypti populations, international travel, and large-scale religious mass gatherings. Dengue virus remains the most established arboviral infection in the Kingdom, particularly in the southwestern regions such as Jazan and the western urban centers of Makkah and Jeddah, where ecological and climatic conditions are conducive to sustained vector survival and transmission. This review synthesizes current evidence on the epidemiology, vector ecology, climatic determinants, diagnostics, and prevention strategies of arboviral diseases in Saudi Arabia. Particular attention is paid to the impacts of rising temperatures, changes in rainfall patterns, urban heat island effects, population mobility, and cross-border movement on vector expansion and disease emergence. The review also identifies gaps in surveillance, diagnostics, insecticide resistance monitoring, and integrated vector management programs. Emerging preparedness strategies include climate-informed early warning systems, Geographic Information System-based risk mapping, multiplex molecular diagnostics, genomic surveillance, and community-based vector control. The review emphasizes the importance of implementing a One Health approach that combines data on humans, the environment, entomology, and climate. Currently, sustained endemic transmission of chikungunya and Zika viruses has not been conclusively demonstrated in Saudi Arabia, but increased environmental suitability and connectivity with other areas highlight the need for proactive surveillance and preparedness. Full article

Extracellular vesicles (EVs) can disseminate replication-competent viral genomes complexed with selected host proteins, enabling stealth cell-to-cell transfer within lipid membrane-enclosed bubbles. In addition to complementing free-virion spread, EV-associated genomes can be protected from neutralizing antibodies and persist under conditions in which classical virion production decreases. Here, we propose a route-resolved framework in which interconnected cellular secretory pathways, including endoplasmic reticulum (ER) remodeling, multivesicular body (MVB) biogenesis, secretory autophagy, and plasma-membrane budding, jointly generate EV heterogeneity and create discrete opportunities for the capture, protection, and export of infectious cargo. We highlight reticulon-3 (RTN3), an ER-shaping protein, as an upstream regulator that can couple infection-induced ER microdomains to endosomal docking and to autophagy-linked trafficking decisions that bias intermediates toward secretion rather than degradation. Supporting this view, transmission electron microscopy of dengue virus-infected cells reveals extensive vesicular remodeling, including irregular MVBs adjacent to the plasma membrane and autophagosome-like double-membrane structures, consistent with altered vesicular routing following RTN3 perturbation. Collectively, these route-resolved, spatially organized spatio-organelle changes support a pathomechanistic model in which RTN3-mediated ER remodeling reshapes ER-endosome-autophagy trafficking interfaces, creating regulated decision points that can be leveraged to stratify infectious EV subsets (with infectivity-linked single-vesicle and quantitative proteomics approaches) and to inform host-directed strategies that curb non-lytic viral dissemination. Full article

Background/Objectives: Since 2023, a significant increase in measles cases has been reported worldwide, and Italy has been among the most affected European countries. In this context, the integration of laboratory and epidemiological data enables timely case classification and helps distinguish between imported and indigenous cases, supporting disease control. However, most studies address only selected aspects of surveillance. Therefore, this study aimed to provide an integrated analysis of virological and epidemiological surveillance activities conducted between November 2023 and December 2025 by the Regional Reference Laboratory in the Emilia-Romagna Region (ERR). Methods: A total of 806 clinical samples (269 urine, 267 oral fluids—saliva or oropharyngeal swabs—and 270 sera) from 291 suspected measles cases were tested by molecular and/or serological methods, and MV genotyping was performed. Samples from discarded cases were also analysed for parvovirus B19 (B19V), human herpesvirus 6 (HHV-6), enterovirus (EV), and varicella zoster virus (VZV), chikungunya virus (CHIKV) and dengue virus (DENV). Results: Of 291 suspected cases, 176 (60.5%) were confirmed. Median age was 33 years, with 46% in the 15–39 year group. Vaccination status was available for 165: 90.3% were unvaccinated, 5.4% had one dose, and 4.2% had two doses. Notably, over half of confirmed cases occurred in areas with vaccine-hesitant communities. MV strain characterisation was performed in 99.4% of MV-RNA positive cases, with 84.3% genotype D8 and 15.6% genotype B3; 83% of strains were of indigenous origin, suggesting an ongoing endemic circulation. Clinical data showed complications in 19.3%, mainly pneumonia and diarrhoea. Additionally, differential diagnosis enabled the identification of the etiological agent in 37.5% of measles/rubella discarded cases, and 37.6% (29/77) tested positive for B19V. Conclusions: The study results highlight that effective measles surveillance must be supported by integrating timely virological diagnosis, molecular and epidemiological investigations, and differential diagnosis, to achieve the WHO goals of eliminating measles transmission. Full article

Aedes aegypti is a primary vector for globally significant arboviruses such as dengue virus (DENV). The mosquito’s metavirome, particularly its insect-specific virus (ISV) component, is recognized as a key modulator of arboviral transmission. However, the natural ecology of these interactions in populations remains poorly understood. This study presents the first comparative analysis of the metavirome in wild-caught A. aegypti from Vietnam based on natural DENV infection status. Metaviromic analysis was performed on 69 DENV-positive pools from six central provinces. The results obtained were compared with previously obtained metaviromic data from 7 DENV-negative pools (from the same region). Analysis suggests the presence of a stable ‘core metavirome’ of 11 ISVs present in both groups. Interestingly, six ISVs were detected only in DENV-negative mosquitoes, which may suggest potential antagonistic interactions requiring further investigation. Conversely, five ISVs were found only in DENV-positive pools, including Aedes partiti-like virus 1 and Aedes anphevirus. The latter may suggest possible synergistic relationships that facilitate arboviral replication. Phylogenetic analysis of prevalent ISVs, such as Phasi Charoen-like phasivirus (PCLV) and Chaq-like virus, revealed patterns of both local circulation and genetic diversity. The findings describe distinct ISV profiles associated with DENV infection in a natural setting, providing a data-driven foundation for hypothesizing specific virus–virus interactions. The data underscores the complexity of the mosquito metavirome. Here, we identified several candidate ISVs for future experimental studies aimed at understanding potential functional impact on arboviral vector competence. Full article

Viral hemorrhagic fevers (VHFs) comprise a heterogeneous group of severe infectious diseases that continue to represent a major global health concern. Although many VHFs remain endemic to regions of Africa, Asia, and the Americas, their wide geographic distribution, together with increasing international travel and global trade, facilitates the importation of cases into non-endemic areas and raises the risk of secondary transmission under favorable ecological and epidemiological conditions. These infections are frequently associated with high case-fatality rates and impose a substantial social and economic burden, including pressure on healthcare systems, disruption of essential services, and long-term physical and psychological sequelae among survivors. Despite notable advances in recent years, therapeutic options for VHFs remain limited. Supportive care continues to represent the cornerstone of clinical management for most infections, while pathogen-targeted therapies are available only for a restricted number of diseases. Monoclonal antibody-based therapies have achieved the most significant regulatory success to date, particularly for Ebola virus disease. In parallel, several small-molecule antivirals have been investigated in preclinical and clinical settings, including during outbreak responses, although inconsistent efficacy and safety concerns have limited widespread approval. Vaccine development has progressed further, with licensed vaccines available for selected VHFs, including Ebola, yellow fever, and dengue, and multiple candidates based on diverse technological platforms advancing through clinical evaluation. In addition to summarizing current therapeutic and vaccine strategies, this review highlights pharmaceutical development considerations relevant to biologic therapeutics and selected vaccine platforms, including formulation stability, pharmacokinetic behavior, delivery routes, storage requirements, and logistical constraints affecting deployment during outbreak responses. Using a comparative cross-pathogen framework, the review synthesizes recent literature to identify translational gaps, regulatory challenges, and future priorities for the development of safer and more effective medical countermeasures against VHFs. Full article

Dengue is a mosquito-borne viral disease which is predominantly endemic in tropical and subtropical countries. In Bangladesh, 321,179 dengue cases were reported in 2023, followed by 101,214 cases in 2024, which highlights a severe and ongoing public health challenge. Dengue transmission risks are shaped by climatic variability, rapid urbanization, socio-economic vulnerability, and healthcare strain. But existing dengue surveillance models remain limited in their ability to capture district-level disparities in Bangladesh. This study aimed to develop a district-level dengue early warning system that integrates climatic, socio-demographic, economic, healthcare, and environmental determinants to generate accurate and interpretable predictions. We examined dengue cases across all 64 districts in Bangladesh from 2017 to 2024, integrating Directorate General of Health Services (DGHS) case records with climate, socio-demographic, economic, and healthcare indicators. Machine learning and deep learning approaches, including Multi-Layer Perceptron (MLP) and Convolutional Long Short-Term Memory (ConvLSTM), were combined with SHAP (Shapley Additive Explanations)-based explainable artificial intelligence. We also used Bayesian spatio-temporal models to capture spatial clustering, temporal dependence, and the lagged transmission effects of dengue. Dengue outbreaks peaked in September 2023, with Dhaka recording 113,233 cases. DENV-4 (Dengue Virus type 4) emerged in 2022, accounting for 27% of infections in 2023. Climate was the strongest predictor of dengue transmission (humidity SHAP = 0.314; minimum temperature SHAP = 0.146; rainfall RR = 1.303). Poverty (SHAP = 0.193) and healthcare capacity (nursing/midwifery density SHAP = 0.073) mostly contributed to dengue prediction. The MLP model achieved the best yearly performance (accuracy = 0.93; ROC-AUC = 0.99), ConvLSTM was the best model in monthly prediction (recall = 0.88; ROC-AUC = 0.81), and Bayesian BYM2_RW2 with lagged effects improved predictive fit (DIC = 3671.055). Our integrated framework delivers transparent, interpretable predictions and district-level early warnings, supporting adaptive dengue outbreak preparedness and resource allocation in Bangladesh. Full article

Plastic pollutants, including phthalates, bisphenol A (BPA), per- and polyfluoroalkyl substances (PFAS), and microplastics (MPs), are increasingly recognized as emerging environmental cofactors that intersect with infectious disease dynamics. These compounds, once considered inert, can alter immune function, reshape host–pathogen interactions, and directly influence viral survival and transmission. In this review, we compile current evidence on the chemistry, environmental occurrence, and biological activity of major plastic-associated pollutants with emphasis on their role in viral infections. Phthalates such as di(2-ethylhexyl) phthalate (DEHP) and its metabolite MEHP modulate innate immune signaling and have been shown to exacerbate infections, including Dengue and Coxsackievirus B3. Other DEHP-like phthalates, such as dibutyl phthalate (DBP), exhibit consistent infection-enhancing effects, while high molecular weight or cyclical phthalates such as polyvinyl acetate phthalate (PVAP) display conflicting results in their modulation of viral infections. BPA, widely detected in human tissues, acts through endocrine and immune disruption, worsening viral myocarditis, and altering influenza outcomes. PFAS, persistent “forever chemicals,” reshape adaptive immune responses and are associated with increased susceptibility, viral persistence, or severity of infection of herpesvirus (HCMV, EBV, HSV-1), hepatitis virus, and influenza infection. Microplastics represent a distinct risk by acting as physical carriers for viruses and bacteria, stabilizing viral RNA, enhancing host cell uptake, and skewing immune responses. Together, these pollutants extend beyond toxicology into virology, providing novel insights into how environmental exposures converge with viral pathogenesis. We highlight mechanistic advances and critical knowledge gaps and propose future directions for integrating environmental health and infectious disease research. Full article

Dengue is the leading mosquito-borne viral cause of human illness and death. More than four billion people globally are at risk of dengue virus (DENV) infection, and most infections are asymptomatic or present with a non-specific febrile illness. We characterise the first complete DENV-2 genome from Sierra Leone, recovered from a febrile adult who tested RT-PCR–positive. The sequence was identified as DENV-2 genotype II, lineage F.1.1. Phylogenetically, the Sierra Leone genome formed a well-supported sister lineage with a 2024 USA DENV-2 genome; both were nested within but clearly diverged from Indian DENV-2 sequences (2021–2022) and were distinct from the Réunion DENV-2 clade. The degree of genetic divergence was incompatible with a recent or direct import of a South Asian lineage and was more consistent with diversification in an under-sampled Indian Ocean/South Asia network or outside this region in Africa. With a single Sierra Leone genome, the source and extent of local transmission remain unresolved. These findings underscore the benefits of integrating differential diagnostics and genomics into routine care for febrile illness and sustaining regional arboviral surveillance. Full article

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

Loop-mediated isothermal amplification (LAMP) is an innovative nucleic acid amplification technique that operates under isothermal conditions and is distinguished by its high analytical efficiency, cost-effectiveness, and operational simplicity. Unlike conventional molecular assays, LAMP does not require sophisticated instrumentation or highly specialized personnel, rendering it particularly suitable for diagnostic deployment in resource-limited settings. Reaction outcomes are typically determined through direct visual inspection, often via colorimetric readouts, further enhancing its applicability in decentralized and point-of-care contexts. Owing to these attributes, LAMP has emerged as a valuable tool for the diagnosis of infectious diseases, particularly in regions with constrained laboratory infrastructure. Its affordability, rapid turnaround time, and ease of implementation support large-scale testing during public health emergencies, including epidemics and outbreaks, thereby contributing to the reduction in disease burden. Timely and accurate pathogen detection using LAMP can substantially strengthen public health responses aimed at controlling and mitigating viral transmission. This review provides an overview of the LAMP methodology, with an emphasis on its application in the detection of viral pathogens with epidemic and pandemic potential. Dengue virus and influenza virus are discussed as representative model infections to illustrate the diagnostic performance and practical advantages of LAMP-based assays. In addition, we explore current challenges and future perspectives for the implementation of LAMP in resource-limited settings, highlighting the need for continued technological refinement and contextual adaptation to maximize its impact on global health initiatives. 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

The Orthoflavivirus genus includes a variety of human-pathogenic, mosquito-borne flaviviruses (MBFs) including dengue, Zika, and West Nile viruses, which pose significant global public health threats. Insect-specific flaviviruses (ISFs) are another group within the genus that exclusively replicate in mosquitoes and are incapable of infecting vertebrates. ISFs have recently attracted growing research interest due to their potential applications in vaccine development. In addition, multiple studies have demonstrated that prior infection with ISFs such as Palm Creek virus and Binjari virus can suppress subsequent infection with human-pathogenic MBFs. This phenomenon, known as superinfection exclusion (SIE), opens the avenue for the potential applications of ISFs in MBF transmission control. This prompted a growing number of studies into ISFs and their interactions with MBFs in mosquito hosts. In this review, we provide an overview on ISFs, with a particular emphasis on the capacity of different ISFs to cause SIE, the current insights into the mechanisms of this phenomenon, and the potential use of ISFs in the SIE-based biocontrol strategies. 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