Search Results (257)

Mosquito-borne diseases pose a significant public health concern globally; however, data on mosquito population dynamics in Taipei, Taiwan are limited and outdated. Updated information on species composition and seasonal abundance is crucial for enhancing vector surveillance and informing effective control strategies. In this study, to investigate the seasonal dynamics of mosquito populations in Taipei, Taiwan, adult females were collected biweekly from June 2023 to May 2025 using CDC light traps baited with ultraviolet light and dry ice. Species identification was performed based on morphological characteristics, and morphologically challenging Culex mosquito species were further confirmed using cytochrome c oxidase I barcoding. Mosquito surveillance from June 2023 to May 2025 yielded 1926 females representing 31 species. Of these, Culex quinquefasciatus, Culex pipiens molestus, Aedes albopictus, and Culex tritaeniorhynchus accounted for over 90% of all specimens. These dominant species exhibited distinct seasonal patterns: Cx. quinquefasciatus occurred year-round, Cx. pipiens molestus predominated during winter and spring, while Ae. albopictus and Cx. tritaeniorhynchus populations peaked in summer. Furthermore, spatial heterogeneity in both mosquito abundance and species composition was noted among the study sites. Monitoring the composition and seasonal dynamics of mosquito species is essential for understanding the epidemiology of mosquito-borne pathogens. These insights can inform more effective and targeted vector control strategies for reducing disease transmission. Such ecological insights can also support One Health approaches by linking human, animal, and environmental factors that influence the transmission of mosquito-borne diseases. Full article

West Nile virus (WNV) is a globally distributed mosquito-borne flavivirus with significant implications for both veterinary and public health. While horses are incidental dead-end hosts, their epidemiological role extends beyond clinical disease, as they can serve as effective sentinel hosts for detecting local viral circulation. Their frequent exposure to mosquito vectors, ability to mount measurable antibody responses, geographic stability, accessibility for monitoring, and the possibility of observation within managed owner–veterinarian systems make them particularly suitable for surveillance within a One Health framework. Evidence from Europe and the Americas demonstrates that equine seroprevalence and field surveillance can identify transmission hotspots, reveal silent circulation, and contribute to the understanding of spatial and temporal risk patterns. The review also addresses key limitations, including vaccination effects, flavivirus cross-reactivity, methodological heterogeneity, and challenges in interpreting serological data across different ecological contexts. Strengthening equine sentinel surveillance through standardized methodologies and integration with predictive and geospatial approaches may improve early warning capacity and support more effective control of WNV and other emerging arboviral diseases. Full article

Aedes aegypti is a major invasive vector in China, where prolonged pyrethroid use has induced resistance, complicating dengue control. This study evaluated the resistance levels of Ae. aegypti to the pyrethroid beta-cypermethrin in Yunnan and explored the underlying mechanisms to inform control strategies. Mosquitoes were collected from five regions of Yunnan in 2015–2016. Larval bioassays, adult diagnostic dose determination, and adult bioassays were conducted to assess resistance to beta-cypermethrin. Mixed-function oxidase (MFO) amount was measured in larvae, and PCR amplification was used to detect mutations in the voltage-gated sodium channel (VGSC) gene. Correlations between enzyme activity, mutations, and phenotypic resistance were analyzed. Larval bioassays indicated that all five populations exhibited resistance to beta-cypermethrin, with resistance ratios ranging from 11.31 to 41.56. The adult diagnostic dose was determined as 0.74668 g/L, with mortality rates ranging from 8.89% to 58.89%, confirming resistance. A significant negative correlation was found between adult mortality and larval LC₅₀ values. MFO amount was closely correlated with resistance levels. The F1534C mutation was the only VGSC mutation detected, and its frequency showed a significant positive correlation with beta-cypermethrin resistance. Our data were collected in 2015–2016; resistance levels may have changed since then, and no confirmatory bioassays were performed by us after 2020. The findings demonstrate that the F1534C mutation and increased MFO amount contribute to enhanced beta-cypermethrin resistance of Ae. aegypti in Yunnan. By linking phenotype resistance to key molecular and biochemical mechanisms, these findings support the continued monitoring of resistance and provide a basis for the evidence-based optimization of dengue vector control strategies. Full article

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

Aedes aegypti transmits viruses to millions of people worldwide. Despite the availability of vaccines, control and monitoring of mosquitoes is mandatory, which in turn requires knowledge of microevolutionary population genetics. Genetic techniques permit the assessment of biological parameters directly linked to the epidemiological importance of the insect (polymorphism, migration, fitness). However, these techniques are costly to most health surveillance services. Even for research laboratories, genotyping and estimation of variability may be unfeasible and time consuming. We conjectured that the wing geometry of Ae. aegypti could serve as an alternative indicator of genetic variability in mosquitoes, as wing shape is a useful taxonomic marker determined by quantitative heritage. We investigated this conjecture by testing if wild Ae. aegypti populations with high genetic variability had higher wing morphological diversity than inbred colonised populations. Using wing geometric morphometrics and microsatellite DNA genotyping of some populational samples, we confirmed this conjecture. The morphological diversity index was partly correspondent with genetic variability indexes such as theta, gene diversity and alleles per locus. Our findings, although circumscribed to the populational samples studied, indicate that wing geometry may be used as a cheap and quick semi-quantitative proxy for genetic variability. Full article

Background: Dengue fever is one of the most common mosquito-borne viral infections, with severe cases characterized by plasma leakage, hemorrhage, and multi-organ involvement. Identification of dengue serotypes and reliable biomarkers is essential for predicting disease progression and guiding timely interventions. Methods: This prospective cohort study was conducted at a super-speciality tertiary care hospital in southern India from July 2024 to July 2025. A total of 69 patients presenting with dengue warning signs were included in the study. Patients were categorized into the severe dengue group (n = 25) and non severe dengue group (n = 44). Clinical data, laboratory findings, dengue serotype, and serial serum samples collected on Days 1, 4, and 8 were analyzed to evaluate the predictive and monitoring efficacy of Interleukin-6 (IL-6) and Interleukin-8 (IL-8), and followed up till discharge. Results: Out of 69 dengue patients with warning signs, 32 dengue-positive patients were serotyped, which included DEN V-1 (31.3%), DEN V-2 (31.3%), DEN V-3 (15.6%), DEN V-4 (18.8%), and mixed DEN V-(2 + 3) (3.1%). Severe dengue patients exhibited a higher frequency of secondary dengue infection (IgG) than primary dengue infection (88% vs. 12%), with statistically significantly higher packed cell volume, hemoglobin levels, high AST levels, and prolonged activated partial thromboplastin time, as well as lower platelet counts and albumin levels. Platelet transfusion was given to 35 dengue patients, which had also resulted in significant length of stay in hospital in comparison to non-transfused patients. IL-6 and IL-8 levels were significantly elevated in severe dengue patients when compared to non-severe dengue patients on Day 1 and Day 4, followed by a decline on Day 8, corresponding with clinical recovery. However, the elevated IL-8 levels were observed to be significantly associated with longer hospital stays, indicating its potential role as an early predictor of disease progression. Conclusions: The observed co-circulation of multiple serotypes reflects the hyper-endemic pattern reported across India. Early measurement of these cytokines IL-6 and IL-8 helps distinguish severe from non-severe dengue among patients presenting with warning signs. IL-6 and IL-8 may have potential as biomarkers for disease severity. However their role in guiding platelet transfusion requires further investigation in non-severe cases and prioritizing timely management for those at higher risk of severe disease. Full article

Yellow fever (YF) remains a re-emerging vector-borne zoonotic disease in tropical regions of the Americas despite the availability of an effective vaccine. In South America, the virus is maintained through a jungle transmission cycle involving Haemagogus and Sabethes mosquitoes and non-human primates (NHPs), which act as amplifying hosts and key epidemiological sentinels. This narrative review examines the current status of YF epizootics in South America, with a focus on the role of NHPs in viral circulation, early detection, and spillover risk to human populations. We synthesize recent evidence on epizootic patterns across endemic countries, the differential susceptibility of neotropical primates, and the ecological and environmental drivers influencing transmission, including deforestation, habitat fragmentation, and human encroachment into forested areas. In addition, we analyze current surveillance strategies, including wildlife monitoring, entomological and genomic surveillance, and their integration within a One Health framework. This review highlights that YF epizootics are expanding geographically and are closely linked to environmental change and human–ecosystem interactions. Strengthening integrated, multidisciplinary surveillance systems is essential to improve early detection, guide vaccination strategies, and prevent human outbreaks. These findings underscore the critical importance of operationalizing the One Health approach to enhance preparedness and response to YF in South America. Full article

West Nile virus (WNV) is a mosquito-borne flavivirus of growing importance for both human and equine health in Europe. Horses are highly susceptible to neurological disease and, because they share ecological exposure with humans, they represent valuable sentinels for detecting local viral circulation within a One Health framework. However, diagnosis of WNV infection in equines is complicated by the short and low-level viraemia, which limits the sensitivity of molecular assays, and by serological cross-reactivity with related flaviviruses and the confounding effects of vaccination. In this narrative review, we summarise the current diagnostic tools for WNV in horses, including direct detection methods (RT-qPCR, virus isolation, antigen detection) and indirect serological approaches (IgM and IgG ELISA, virus neutralisation tests), and discuss their practical performance and constraints in clinical and surveillance settings. We further examine equine surveillance systems, passive clinical reporting, active serosurveys and sentinel cohorts, and their integration with vector, avian and environmental monitoring. Key challenges include methodological heterogeneity, limited access to confirmatory testing and variable cross-sector data sharing. Finally, we outline future directions, highlighting the need for harmonised laboratory protocols, innovative field-deployable diagnostics, genomic surveillance and integrated, multi-source monitoring systems to strengthen early warning capacity and improve preparedness for WNV outbreaks in equine populations. Full article

Spinosad is a naturally derived insecticide obtained from a soil-dwelling bacterium and is widely used against various agricultural and public-health pests. Although resistance to spinosad has been reported in several pest groups—including thrips, fruit flies, beetles, lepidopterans, and even mosquitoes—no study to date has evaluated its resistance status in the house fly, Musca domestica L. (Diptera: Muscidae). The present study provides the first field-based assessment of spinosad resistance in larvae of M. domestica, based on field-collected populations from Türkiye, and offers the first baseline data on larval susceptibility for this species. House fly larvae collected from seven provinces were exposed to a series of spinosad doses, and LD₅₀ values were calculated using probit analysis. According to the results, LD₅₀ values showed variability of up to approximately 18-fold, ranging from 0.002 g a.i./m² in the Adana population to 0.036 g a.i./m² in the Şanlıurfa population. The corresponding resistance ratio (RR₅₀) values calculated based on the most susceptible population (Adana) ranged from 1.0 to 18.0, indicating low-to-moderate variation in baseline tolerance among the tested field populations. Despite these differences at low doses, the minimum operational dose of 0.25 g a.i./m² consistently produced 97–100% emergence inhibition in all populations. Overall, no high or very high resistance levels were detected across the tested populations. These findings indicate that, despite detectable differences in baseline tolerance, spinosad remains a highly effective larvicide for house fly management. The establishment of these baseline data is essential for future resistance-monitoring programs, and continued surveillance is strongly recommended to detect early shifts in susceptibility before operational resistance emerges. Full article

Insect bites are a common cause of skin irritation and can contribute to disease transmission through vector-borne pathogens. Early identification of the likely biting organism can assist preliminary guidance (e.g., monitoring for warning signs, considering exposure history) and may reduce complications through timely follow-up. This paper studies a compact attention-guided learning framework for multiclass insect-bite image classification under strict storage constraints. A teacher network (BiteAI-T) based on MobileNetV3-Small is trained with spatial attention pooling to emphasize lesion-relevant regions while maintaining an efficient backbone. A lightweight depthwise-separable student (BiteAI-S) is trained using multi-level knowledge distillation that combines softened-logit matching with intermediate supervision through attention-map alignment and pooled-feature matching. Model storage is further reduced through weight-only quantization-aware training using an LSQ-inspired learnable scaling factor; BatchNorm running statistics are frozen during quantization fine-tuning to improve stability. Experiments on an eight-class dataset (ants, bed bugs, chiggers, fleas, mosquitos, no bites, spiders, ticks) show that BiteAI-T reaches 93.75% test accuracy. For deployment, we export (i) a TorchScript Lite teacher artifact (BiteAI-T_Lite, 2.35 MB) and (ii) a weight-only int8 student artifact (BiteAI-S_int8, 0.992 MB). Comparative results are also reported for an SVD-compressed + fine-tuned FP16 variant (92.66% test accuracy, 2.84 MB), illustrating accuracy–size trade-offs across compression strategies. Full article

Phytotelmata are small, plant-held water pools that support unique assemblages of fauna and flora. Aquatic Diptera are a significant component of these microecosystems. Based on an exhaustive review of over 100 years of published literature, a global database of phytotelmata-associated aquatic Diptera with Bromeliaceae and Zingiberales (7 families) was compiled to explore diversity and ecology and identify gaps in the research. This database is designed to provide a valuable baseline and to serve as an objective, informed tool for future monitoring and research. A total of 4979 unique associations between aquatic Diptera larvae and 117 species in 26 genera of Bromeliaceae and 27 species in 10 genera across 6 families of Zingiberales were assembled in the database. These reported aquatic Diptera span 369 species, 80 genera, and 14 families, and include taxa with diverse ecological roles as detritivores, filter feeders, predators, and prey. Mosquitoes (Culicidae) had the greatest number of documented species (227), and non-biting midges (Chironomidae) had the greatest number of documented genera (26) in the dataset. Several mosquito vectors (e.g., Anopheles, Aedes, and Culex) also complete their life cycles in these habitats, although records of vector mosquitoes compose only 6% of the assembled data. Because phytotelmata provide year-round aquatic refugia, they sustain regional aquatic Diptera diversity yet are threatened by habitat loss and other anthropogenic pressures. Furthermore, despite the important role of phytotelmata in freshwater ecology, diversity in these ephemeral freshwater habitats remains under-documented. This comprehensive analysis of existing literature establishes the first global baseline for aquatic Diptera in phytotelmata and offers a foundation for biodiversity assessments, conservation strategies, and future ecological research. Full article

Background: Rift Valley fever virus (RVFV) is a significant mosquito-borne zoonotic virus with high public health and veterinary importance in Africa and the Middle East. Reliable diagnostic assays for detecting antibodies and assessing their functional neutralizing capacity are essential for surveillance programs, vaccine monitoring, and outbreak preparedness. Objective: This study evaluates and compares the analytical performance of a competitive enzyme-linked immunosorbent assay (cELISA) and a virus neutralization test (VNT) for detecting RVFV antibodies in vaccinated sheep sera, establishing an integrated laboratory workflow for virus titration, serological detection, and functional neutralization. Methods: Twenty serum samples were collected from sheep pre-vaccination and one month post-vaccination with Smithburn live attenuated RVFV vaccine. Sera were tested using a commercial multispecies RVFV competitive ELISA to detect antibodies specific to the viral nucleocapsid protein. Viral titration was conducted in Vero cells, and 50% tissue culture infective dose (TCID₅₀/0.1 mL) was calculated using the Reed and Muench method. VNT was performed at 24, 48, 72, and 96 h after infection with different viral doses (10² to 10⁵ TCID₅₀/0.1 mL), and the neutralizing ability of serial serum dilutions (1:2 to 1:1024) was tested. Compared with the control, protection was determined by cytopathic effect (CPE) inhibition. Results: ELISA revealed robust antibody signals up to a 1:32 dilution, with signal-to-noise (S/N) < 40%, whereas for higher dilutions, antibody detection became inconclusive or negative. Virus titration was performed to verify a stock concentration of 10^6.5 TCID₅₀/0.1 mL. The VNT exhibited time- and dose-dependent kinetics; high protection rates (≥97) were observed at 1:2–1:8 dilutions against 10²–10³ TCID₅₀/0.1 mL challenge doses; however, neutralizing efficacy decreased significantly at higher viral loads and higher serum dilutions. While cELISA and VNT results correlated strongly at low serum dilutions, the cELISA showed decreased sensitivity at dilutions ≥ 1:64, where the VNT remained capable of detecting functional neutralizing activity. Conclusions/Discussion: The results demonstrate that while both assays correlate well at high antibody concentrations, they diverge at lower concentrations. This discrepancy highlights the functional difference between binding antibodies (N-protein) and neutralizing antibodies (Gn/Gc glycoproteins). Consequently, the cELISA is ideal for rapid screening, whereas the VNT is indispensable for confirming functional immunity. Integrating both assays provides a more accurate immunological profile for RVFV surveillance and vaccine evaluation. Full article

Insecticide resistance in Aedes aegypti (Linnaeus, 1762) poses a major challenge for vector control programs, undermining the effectiveness of chemical tools to mitigate both nuisance biting and the transmission of vector-borne diseases. Previous studies have documented widespread resistance to multiple adulticide active ingredients across Florida, particularly pyrethroids, along with high prevalence of knockdown resistance (kdr) mutations. Continued resistance monitoring is essential for guiding treatment decisions and detecting shifts in susceptibility over time. In collaboration with mosquito control programs across Florida, we assessed the susceptibility of 78 Ae. aegypti populations to up to six active ingredients, conducting 396 independent CDC bottle bioassays and calculating hazard ratios relative to a susceptible Ae. aegypti strain. For pyrethroids, 24 h post-exposure mortality was used to evaluate phenotypic recovery from knockdown. Hazard ratios revealed Ae. aegypti populations were more susceptible to organophosphate adulticide active ingredients, while the lowest hazard ratios, indicating higher resistance, were observed for sumithrin, deltamethrin, etofenprox, and permethrin, respectively. Evidence of knockdown resistance and recovery after 24 h was present across all pyrethroid exposures, with the highest levels following treatment with etofenprox and sumithrin. These findings confirm that pyrethroid resistance remains a significant barrier to Ae. aegypti control and provide updated, operationally relevant resistance data that can complement existing guidance and support evidence-based vector management strategies. Full article

During the 2024/2025 wet season, Townsville had its first sustained autochthonous outbreak of dengue disease caused by dengue virus type 2 (DENV-2), the second locally transmitted outbreak of dengue since 2014 following the introduction of wMel strain Wolbachia-infected mosquitoes, a control strategy for dengue virus (DENV) and other Aedes-transmitted arboviruses. In comparison to two recorded locally acquired cases of dengue in 2020, the 2024/2025 outbreak resulted in sixteen cases in two inner-city suburbs of Townsville during the wet season associated with higher-than-average rainfall. This second dengue outbreak since 2014 highlights that Townsville and other north Queensland communities where Wolbachia mosquito programs have been deployed remain vulnerable to DENV incursions and local disease outbreaks despite the apparent high coverage of Wolbachia-infected mosquitoes. Whilst these control strategies have likely contributed to a reduction in the number and frequency of autochthonous DENV outbreaks in north Queensland, ongoing maintenance and monitoring of Wolbachia-infected mosquito coverage is necessary, together with timely review and improvement in dengue awareness and prevention health promotion activities in the community. Full article

Lymphatic filariasis (LF) is a mosquito-borne neglected tropical disease targeted by the World Health Organization (WHO) for global elimination as a public health problem. Sixteen Pacific Island countries and territories were historically endemic, and eight have now met the WHO criteria for elimination as a public health problem. Elimination as a public health problem does not imply zero transmission. Rather, it denotes that LF prevalence has been reduced below a defined threshold at which community transmission can be sustained. Following validation of elimination, the WHO recommends post-validation surveillance (PVS) to detect potential re-emergence of LF as a public health problem. However, implementing PVS is challenging in Small Island Developing States with dispersed populations, limited workforce capacity, resource constraints, and competing health priorities. The ‘Voices and Visions: Building Partnerships for Integrated Serosurveillance of LF and Other Infectious Diseases in the Pacific Islands’ meeting was held in Brisbane, Australia, from 8–10 July 2025. Fifty-one delegates, including Pacific LF programme managers, WHO representatives, global health partners, and academic researchers, reviewed regional PVS progress, discussed the newly released WHO guidelines for the implementation, monitoring, and evaluation of PVS, planned for PVS implementation, and explored novel multiplex bead assay (MBA) serological analysis methods to strengthen regional coordination for its development as a public health tool. Five broad themes emerged. First, the new WHO Monitoring and Epidemiological Assessment of Mass Drug Administration in the Global Programme to Eliminate Lymphatic Filariasis: A Manual for National Elimination Programmes, 2nd edn needs to be operationalised to meet decision-making needs across diverse Pacific settings. Second, integrating LF-PVS with existing surveys and health service activities could improve efficiency and long-term sustainability. Third, regional coordination and alignment of funding cycles will require high-level collaboration. Fourth, community engagement is essential to strengthen demand for PVS. Finally, while at an early stage and with further evidence needed, MBA laboratory methods hold promise for cost-effective, feasible integrated multi-pathogen serosurveillance. Full article