Search Results (525)

Background: In recent decades, malaria vector species distribution and insecticide resistance have taken new colonization steps across Africa. Understanding the malaria vector insecticide resistance status, blood meal source, and species composition is of paramount importance in designing evidence-based vector control strategies. This study assessed the blood meal sources, sporozoite (infectivity) rate, and knockdown resistance allele’s frequency in female Anopheles arabiensis in chosen villages of Jabi Tehnan District, Northwest Ethiopia. Methods: The host-seeking and resting Anopheles gambiae s.l. were collected using human landing catches (HLCs), CDC light traps (CDC-LTs), pyrethrum spray catches (PSCs), and pit shelters (PSs) both indoors and outdoors. The analysis of both blood meal sources and circumsporozoite proteins was performed using enzyme-linked immunosorbent assay (ELISA). The detection of knockdown resistance gene mutations and species identification were conducted using a polymerase chain reaction (PCR). Results: A total of 5098 female Anopheles gambiae s.l. were collected. Of these, 1690 (33.2%) were collected from HLCs, 1423 (27.9%) from CDC light traps, 1635 (32.0%) from PSCs, and only 350 (6.9%) from pit shelters (PSs). Of these, 57.2% (n = 2915) female Anopheles mosquitoes were collected indoors using CDC light traps (CDC-LTs), human landing catches (HLCs), and pyrethrum spray catches (PSCs), while 38.2% (n = 2183) were collected outdoors using human landing collection (HLC), CDC light traps (CDC-LTs), and artificial pit shelters (PSs). Molecular identification to the species level showed that among the 530 An. gambiae s.l. samples analyzed using PCR, 96.03% (509) were An. arabiensis, and 3.97% (21) were unidentified species. The biting peak was found to be from 22:00 to 00:00 h for An. arabiensis. However, their activity decreased sharply after 23:00 to 00:00 h. The distribution of knockdown resistance genes in the tested specimens of An. arabiensis consisted of 1.4% (n = 3) heterozygous resistant (RS), 17.9% (n = 38) homozygous resistant (RR), and 80.7% (n = 171) homozygous susceptible (SS) genotypes. A higher proportion of Anopheles mosquitoes analyzed for blood meal analysis had a human blood meal origin at 13.1% (n = 47), followed by bovine at 8.9% (n = 32) and mixed at 5.8% (n = 21). Conclusions: The dominant malaria vector species was Anopheles arabiensis in the study area with a higher human blood meal origin. The Kdr gene was confirmed in the tested An. arabiensis, indicating that an alternative insecticide class should be used in the study area. Full article

Dirofilariosis, a parasitic disease caused by nematodes of the genus Dirofilaria, primarily affects dogs but can also infect other carnivores and, more rarely, humans. In Europe, the most commonly involved species are D. immitis and D. repens, transmitted through the bites of mosquito vectors. This study, conducted in Tulcea County between April and October 2024, aimed to determine the prevalence of D. immitis and D. repens in mosquitoes. A total of 1507 mosquitoes were collected and grouped into 76 pools, and subsequently molecular analysis was carried out using qPCR. The estimated infection rate (EIR) was calculated using statistical methods available in the ‘binGroup’ package in R, which allow the determination of the point estimate and confidence interval (CI) for a single binomial proportion in group testing. The study revealed a high infection rate with D. immitis (48%), while D. repens was identified in only two pools. The species with the highest vector potential was Anopheles maculipennis (PTP = 75%, EIR = 0.1168 with both Dirofilaria species), followed by Aedes vexans. Notably, Aedes albopictus was identified for the first time in Tulcea, and all individuals were positive for D. immitis. Simulations of local thermal conditions using the proposed model show that the favorable time window for mosquitoes will increase until 2100. Our results indicate an established and active transmission cycle of D. immitis in the region, a situation projected to intensify with climate change requiring urgent monitoring. Full article

Polymeric optical waveguides represent an essential component in photonic technology thanks to their ability to guide light through controlled structures, enabling applications in telecommunications, sensors, and integrated devices. With the development of new materials and increasingly versatile manufacturing methods, these structures are being integrated into various systems at a rapid pace, while their dimensions are constantly being reduced. This article explores the main fabrication methods for polymeric optical waveguides, such as traditional and maskless photolithography, laser ablation, hot embossing, nanoimprint lithography, the Mosquito method, inkjet printing, aerosol jet printing, and electrohydrodynamic (EHD) printing. The operating principle of each method, the equipment and materials used, and their advantages, limitations, and practical applications are evaluated, in addition to the propagation losses and characterization of the waveguides obtained with each method. Full article

Background: The global health burden of mosquito-borne viruses, including dengue, yellow fever, Zika, and chikungunya, is rising due to climate change and globalisation, which favour mosquito habitat expansion. The genetic diversity of these viruses complicates the development of virus-specific vaccines or antivirals, highlighting the need for pan-viral strategies. As the common vector for these pathogens, mosquitoes and specifically their salivary proteins represent a promising target for such interventions. Mosquito saliva, secreted into the skin during biting, has immunomodulatory effects that can enhance host susceptibility to infection, but these mechanisms are not well defined in humans. Methods: The objective of this study was to determine whether AGS-v PLUS, a vaccine targeting mosquito salivary antigens, could modulate the human skin immune response to mosquito biting and potentially promote antiviral bystander immunity. In a Phase I trial, healthy volunteers were vaccinated with AGS-v PLUS (with or without adjuvant) or placebo, and three weeks later, they were exposed to bites from Aedes albopictus and Aedes aegypti mosquitoes. Skin biopsies from bitten and unbitten sites were analysed by transcriptomic profiling. Results: In placebo recipients, mosquito biting elicited a marked adaptive immune response at 48 h, characterised by CD4⁺ Th1 and CD8⁺ T cell signatures and leukocyte recruitment. While responses to Ae. aegypti and Ae. albopictus bites were broadly similar, those to Ae. albopictus were stronger. Vaccination with AGS-v PLUS, particularly with adjuvant, enhanced Th1 and CD8⁺ T cell-associated gene expression while suppressing pathways linked to neutrophilic inflammation and epithelial stress, which together may provide enhanced antiviral capacity. Conclusions: These findings demonstrate that targeting the host response to mosquito saliva via vaccination can reprogram the skin’s immune response to mosquito bites, supporting a novel and broadly applicable pan-viral strategy to mitigate the impact of arboviral diseases. Full article

Chikungunya fever (CHIKF), which is caused by the Chikungunya virus (CHIKV), has rapidly spread across the globe in recent years, leading to its listing as a public health concern by the World Health Organization. In 2019, the first local outbreak of Asian-type CHIKF was reported in Xishuangbanna, Yunnan Province, China, with 88 CHIKV nucleic acid-positive cases detected from clinical specimens. To further investigate the biological characteristics of the virus strain responsible for this outbreak, we reconstructed the 625D6h strain using reverse genetics and tested its growth kinetics in different cell lines. The results showed a strong replication capacity in the Aedes albopictus C6/36 insect cell line but a weaker one in mammalian cell lines. The virus’s high replication capacity in mosquito cells is an interesting phenotype that warrants further study to determine if it influences vector adaptation and transmission dynamics in endemic settings. The study also found that two DHODH inhibitors, ML390 and vidofludimus, could effectively inhibit CHIKV replication in vitro. The infectious clone created in this study provides a useful tool for studying the recently prevalent Asian-type strain in China, supporting the subsequent development of prevention and treatment methods. Full article

It is widely recognized that mosquitoes are attracted to ultraviolet (UV) light traps in field and semi-field trials. However, the specific characteristics of mosquito behavioral responses to UV light remain poorly defined. Moreover, the molecular mechanisms underlying their phototactic behavior remain unexplored. Here, we characterized mosquito photobehavior under UV light in a laboratory setting using three experimental apparatuses. Our findings indicate that mosquitoes exhibit strong attraction to low-intensity UV light, yet show no preference between high-intensity UV light and darkness. Video recordings and automatic analyses of photobehavior under low-intensity UV light revealed that mosquitoes preferred the window illuminated by UV light over an unilluminated window and were more active when exposed to UV light. Through RNA interference (RNAi)-mediated knockdown of opsins highly expressed in the adult stage of Culex quinquefasciatus, we identified CqOpsin3, CqOpsin5, and CqOpsin6 as crucial mediators of UV phototaxis. This study provides methods for characterizing mosquito photobehavior under UV light in the laboratory, and represents the first mechanistic investigation into UV light-mediated attractive behavior in mosquitoes. Full article

Background/Objectives: Chikungunya virus (CHIKV), a mosquito-borne single-stranded RNA virus belonging to the genus Alphavirus (family Togaviridae), causes large-scale outbreaks. However, no specific treatment for CHIKV infections is currently available. Berberine and emodin are plant-derived compounds with anti-CHIKV activities. This study aimed to evaluate the antiviral efficacy of liposomes containing berberine (LB) or emodin (LE) against CHIKV in vitro, since nanocarriers incorporating zwitterionic polymers are known to enhance the biostability, biocompatibility, and therapeutic efficacy of drug candidates. Methods: Liposomes were synthesized and characterized, and cell viability was assessed to determine appropriate concentrations for subsequent assays. Confocal microscopy, antiviral assays, and western blotting were performed in BHK-21 and Huh7 cells. Results: In BHK-21 and Huh7 cells, LB and LE were well tolerated at concentrations of 5 and 10 µM, respectively. In both cell types, liposomes were internalized; LE was predominantly localized in the cytoplasm, whereas LB was also detected in the nucleus. EGCG, used as a standard drug against CHIKV in antiviral assays, exhibited virucidal activity and inhibited RNA replication and multiple stages of the CHIKV replication cycle in BHK-21 and Huh7 cells. Both the nanoformulations and EGCG consistently suppressed the expression of CHIKV replicase and virion proteins. Conclusions: These findings highlight the potential of berberine- and emodin-loaded liposomes as antiviral agents against CHIKV infection. Full article

Background: Dengue fever is an arboviral infection transmitted by Aedes mosquitoes that has recently become a public health concern also in Europe, causing many outbreaks of autochthonous cases. Methods: We retrospectively retrieved dengue cases in returning travelers from tropical areas diagnosed at the Luigi Sacco Hospital between January 2018 and December 2024. All patients with positive serology for DENV (IgM alone or IgM and IgG or neutralizing antibodies detection) and/or positive real-time polymerase chain reaction (RT-PCR) for DENV RNA on plasma and urine were considered. Analyses were descriptive. Results: This analysis included 159 travelers with confirmed (n = 138; 86.8%) or probable (n = 21; 13.2%) dengue fever. The median age was 38 years (interquartile range [IQR] 30–50); 87 (54.7%) were females. The median time between symptom onset and seeking medical attention was four days (IQR 3–6); 29.6% required hospitalization, with a median stay of four days (IQR 0–5). The most common symptoms included fever (100%), myalgia (52.2%), and headache (49.1%). Laboratory findings revealed thrombocytopenia (53.8%), leukopenia (64.1%), elevated ALT (51.9%), and LDH (60.2%). Among the confirmed cases, 128 (92.8%) were diagnosed with RT-PCR. Serotypes 1 and 2 were the most prevalent (28.9% and 27.3%, respectively). Most cases were classified as dengue without warning signs (150, 94.3%), eight cases (5.0%) as dengue with warning signs, and one as severe dengue. Conclusions: Dengue fever is an important cause of fever among travelers returning to Italy from endemic areas. Although severe dengue is rare among travelers, further prospective studies need to address this issue. Diagnosis should be pursued by using molecular tools because of cross-reactivity with other arboviruses. Full article

Dengue is a rapidly spreading mosquito-borne viral infection, with increasing reports of outbreaks globally. According to the World Health Organization (WHO), by 30 April 2024, over 7.6 million dengue cases were reported, including 3.4 million confirmed cases, more than 16,000 severe cases, and over 3000 deaths. As dengue remains endemic in many regions, there is a critical need for the development of new vaccines and manufacturing processes that are efficient, cost-effective, and capable of meeting growing demand. In this study, we explore an alternative process development pathway for the future manufacturing of a dengue vaccine, utilizing Komagataella phaffii (Pichia pastoris) as the host organism, one of the most promising candidates for the expression of heterologous proteins in vaccine development. It combines the speed and ease of highly efficient prokaryotic platforms with some key capabilities of mammalian systems, making it ideal for scalable and cost-effective production. The key outcomes of our research include (i) demonstrating the versatility of the Komagataella phaffii platform in the production of dengue viral-like particles (VLPs); (ii) optimizing the culture process using Design of Experiments (DoE) approaches in small-scale bioreactors; (iii) developing a novel purification platform for enveloped VLPs (eVLPs), and (iv) establishing alternative biophysical characterization methods for the dengue vaccine prototype. These findings provide a promising foundation for efficient and scalable production of dengue vaccines, addressing both technical and operational challenges in vaccine manufacturing. Full article

Background: Genus Dirofilaria consists of 27 species of parasitic nematodes, 7 of which have been reported to cause disease in humans. The transmission of the parasitic larva to humans and other mammals occurs through the bite of an infected mosquito, which, in this case, in addition to being the intermediate host, acts also as a disease transmission vector. The initial diagnosis of a patient with dirofilariasis is almost always incorrect, and in a large number of cases, the final diagnosis is only achieved retrospectively, thanks to the findings of the histopathological examination. Therefore, the purpose of the present review is to collect, analyze, summarize and present the relevant epidemiological, clinical, diagnostic, parasitological, therapeutic and prognostic data concerning the aforementioned localization of dirofilariasis in a systematic manner. Methods: An electronic search was performed in PubMed, the Scopus and Ovid databases and in Google Scholar, with them being accessed for the last time on 2 August 2025. This was followed by a manual search, and references were used to identify relevant articles. Results: The present review retrieved 32 publications discussing 43 cases of human intraoral dirofilariasis. As per the study design, the records were published in 2015–2025, and the cases presented by them were observed in 1951–2024. Conclusions: The aim of the present review is to summarize the relevant epidemiological, clinical, diagnostic, parasitological, therapeutic and prognostic data regarding the oral localization of dirofilariasis, a zoonotic helminthiasis which is transmitted by mosquitoes. Even though its manifestation in the oral cavity appears to be extremely rare, dentists and other clinicians should be familiar with this entity and should include it in the differential diagnosis of any solitary nodule with submucous localization, especially in patients living in endemic regions or who have a history of recent travel to an endemic region. Climate change on the one hand and the increase in international travel on the other are estimated to make dirofilariasis more common in countries from which it used to be absent. Full article

Disinsection of aircraft and other conveyances is recommended to prevent the international spread of disease-carrying mosquitoes. A systematic review synthesized the effectiveness of adult mosquito disinsection aboard international air, marine, and land conveyances, using literature available up to 31 May 2025. Nineteen experimental trials, nine of which included an unexposed control arm, were synthesized. The studies were generally of poor quality with high risk of bias, and adherence to WHO guidelines was 33.30% (range: 18.20–60.5%). Across comparator trials of aircraft disinsection, the odds of mosquito mortality in the treated groups compared to control groups was 163.60 (95% CI 147–182), and the relative risk of mosquito death was 14.24 (95% CI 12.99–15.63). The direction of effect was consistent across mosquito species, methods of disinsection, types of aircraft, and insecticides, though the magnitude of the effect varied widely. The only WHO-recommended insecticide tested in a controlled trial was 2% d-phenothrin, which demonstrated an odds ratio of 171.70 (95% CI 139.10–212) and a relative risk of 20.08 (95% CI 16.53–24.43) for mosquito mortality. The lack of adherence to WHO guidelines raises uncertainty about the real-world effectiveness of disinsection. Full article

Background/Objectives: Malaria is a prominent vector-borne disease, with a high mortality rate, particularly in children under five years old. Despite the use of various insecticides for its control, the emergence of resistant mosquitoes poses a significant public health threat. Acetylcholinesterase (AChE) is a crucial enzyme in nerve transmission and a primary target for insecticide development due to its role in preventing repeated nerve impulses. Recent studies have identified difluoromethyl ketone (DFK) as a potent inhibitor of both sensitive and resistant Anopheles gambiae acetylcholinesterase (AgAChE). This study aimed to identify novel AgAChE inhibitors that could be explored for malaria prevention. Methods: We performed a virtual screening on the PubChem database using a pharmacophore model from difluoromethyl ketone-inhibited AgAChE’s crystal structure. The most promising compound was then subjected to molecular docking and dynamics studies with AgAChE to confirm initial findings. ADMET and agrochemical likeness (ag-like) properties were also analyzed to assess its potential as an agrochemical agent. Results: PubChem18463786 was identified as the most suitable compound from the virtual screening. Molecular docking and molecular dynamics studies confirmed its strong interaction with AgAChE. The ADMET and ag-like analyses indicated that PubChem18463786 possesses physicochemical properties suggesting a high probability of non-absorption in humans and meets the criteria for agrochemical similarity. Conclusions: Our findings suggest that PubChem18463786 is a potential AgAChE inhibitor candidate. After validation through in vitro and in vivo experiments, it could be exploited for malaria prevention and serve as a lead compound for the synthesis of new, more effective, and selective agrochemical agents. Full article

Background: Aedes albopictus, the tiger mosquito, is an invasive exotic species native to Southeast Asia, currently established in Europe, including Spain and the region of Navarre. This vector poses an emerging public health threat due to its ability to transmit dengue, Zika, and chikungunya viruses, which cause diseases in humans. This study presents novel findings by documenting the progression of the invasion of Aedes albopictus in the Navarre region in northern Spain, tracing its status from initial absence to its definitive establishment in certain areas. Methods: Surveillance in Navarre within the LIFE-IP NAdapta-CC project was conducted through a network of strategically placed ovitraps and adult traps to collect eggs and adult mosquitoes. Awareness campaigns and outreach events were organized to inform local authorities and the public about monitoring results and preventive measures. Results: Monitoring confirms Aedes albopictus’ expansion across Navarre despite training, information dissemination, and control efforts, including entomological containment in targeted areas. Conclusions: Eliminating breeding sites remains the most effective strategy to limit its spread. Complete eradication is unlikely given its invasive nature, and the species is expected to expand and colonize at least part of the region in the coming years. Full article

The accurate identification of mosquito species is critical for effective mosquito surveillance and control, especially when presented with morphologically similar species like Aedes aegypti and Aedes sierrensis. Damaged specimens and morphologically similar life stages such as eggs and larvae make it difficult to distinguish Aedes aegypti from Aedes sierrensis using microscopy and taxonomic keys. To address this, the AegySierr.ID-qPCR assay, a multiplex quantitative PCR assay that utilizes single-nucleotide polymorphisms within the mitochondrial cytochrome oxidase subunit I gene, was developed to distinguish between these two species. The assay was tested on DNA extracted from the eggs, larvae, and adults of both species, as well as from environmental DNA (eDNA) collected from natural mosquito reproduction sites. It demonstrated a high diagnostic accuracy across multiple life stages, with a sensitivity exceeding 95% for most groups and specificity exceeding 90%, except for field-collected adult Ae. sierrensis (75%). For eDNA samples, the assay achieved 100% sensitivity and 94% specificity for samples classified as Ae. sierrensis and 91% sensitivity and 86% specificity for Ae. aegypti. A two-graph receiver operating characteristic analysis was also used as an alternate method with which to establish Ct thresholds for interpreting results from unknown samples. The AegySierr.ID-qPCR assay enables the rapid and sensitive identification of Ae. aegypti and Ae. sierrensis from specimens and eDNA, and may be of use in mosquito surveillance programs. Full article

Background: Mosquitoes from the Aedes (Ae.) genus are vectors of dengue, Zika, chikungunya, and other arboviruses, posing a significant public health threat. In 2005, Aedes aegypti was detected for the first time in Madeira Island, Portugal, in the city of Funchal, and has since become established in the region. In 2017, Aedes albopictus was detected for the first time in mainland Portugal. These invasion events require targeted entomological surveillance, which demands substantial human resources and a high management capacity for traditional vector monitoring. Following promising results obtained in laboratory conditions, a field-deployable model of a bioacoustic sensor for the automatic classification of mosquitoes integrated with a Biogents Sentinel trap as part of the VECTRACK system was tested in three regions in Portugal. Methods: The VECTRACK system was deployed in three locations: Funchal on Madeira Island, and Palmela and Algarve on mainland Portugal. Catch bags were manually inspected at intervals ranging from daily to weekly, resulting in a total of 38 captures in Madeira, 10 in Palmela, and 7 in the Algarve. Manual identifications were compared with those generated by the VECTRACK system, and the degree of correlation between the two datasets was assessed using Spearman’s rank correlation coefficient. Results: A total of 176 mosquitoes were captured in Madeira, 732 in Palmela, and 143 in the Algarve. Both manual and sensor-based identifications demonstrated similar performance, with high correlation observed between the two methods. Spearman’s rank correlation coefficients indicated high agreement for both female and male mosquitoes across all sites: Madeira: females = 0.84, males = 0.92, Palmela: females = 0.99, males = 0.84, Algarve: females = 0.98, and males = 0.99, all with p-values < 0.001. Conclusions: The VECTRACK system demonstrated strong performance in accurately distinguishing mosquitoes from non-mosquitoes, differentiating between Aedes and Culex genera, and identifying the sex of individual specimens. These promising results provide a solid foundation for the development of automated early warning systems and enhance mosquito surveillance strategies, which are critical for timely responses to potential vector-borne disease outbreaks. Full article