Search Results (84)

The term ‘entomo-virology’ arose because of the confluence of entomology and virology, focused on deepening the knowledge about the interactions between vectors and viruses and the aspects that involve hosts and the environment. Based on this, entomo-virological surveillance was proposed, aiming to develop tools that strengthen prevention for arboviral disease and vector control strategies. This review aims to present a narrative synthesis regarding the component elements of the concept of entomo-virology. In addition, the applications and tools for the surveillance of viruses and vectors, their implementation challenges, and perspectives are discussed. Full article

Arboviruses are a growing concern in many nations. Several reports of arboviral outbreaks have been recorded globally in the past decade alone. Repeated arboviral outbreaks in developing countries have consistently highlighted vulnerabilities in disease surveillance and response systems, exposing critical gaps in early detection, contact tracing, and resource allocation. The 2024 Dengue fever outbreak in Ghana, which recorded 205 confirmed cases out of 1410 suspected cases, underscored the urgent need to evaluate the country’s preparedness for arboviral outbreaks, given the detection of competent vectors in the country. A retrospective analysis of Ghana’s 2009–2013 pandemic influenza response plan revealed significant deficiencies in emergency preparedness, raising concerns about the country’s ability to manage emerging arboviral threats. This review assessed Ghana’s current arboviral outbreak response and preparedness by examining (a) the effectiveness of vector control measures, (b) the role of early warning systems in mitigating outbreaks, (c) laboratory support and diagnostic capabilities, and (d) community engagement strategies. It highlights the successes made in previous outbreaks and sheds light on several gaps in Ghana’s outbreak response efforts. This review also provides recommendations that can be implemented in many countries across Africa as they brace themselves for any arboviral outbreak. Full article

Neuroinvasive arboviruses such as tick-borne encephalitis virus (TBEV), West Nile virus (WNV), Usutu virus (USUV), and Toscana virus (TOSV) have (re-)emerged with increasing incidence and geographic range. We analyzed the epidemiology of arboviral infections in Croatia during the 2024 transmission season. A total of 154 patients with neuroinvasive diseases (NID), 1596 horses, 69 dead birds, and 7726 mosquitoes were tested. Viral RNA was detected using RT-qPCR. IgM/IgG-specific antibodies were detected using commercial ELISA or IFA, with confirmation of cross-reactive samples by virus neutralization test. RT-qPCR-positive samples were Sanger sequenced. Arboviral etiology was confirmed in 33/21.42% of patients with NID. WNV was most frequently detected (17/11.03%), followed by TBEV (10/6.49%), USUV (5/3.24%), and TOSV (1/0.64%). WNV infections were reported in regions previously known as endemic, while in one continental county, WNV was recorded for the first time. USUV infections re-emerged after a six-year absence. In addition to human cases, acute WNV infections were recorded in 11/395 (2.78%) of horses and two dead crows. WNV IgG seropositivity was detected in 276/1168 (23.63%) and TBEV IgG seropositivity in 68/428 (15.88%) horses. None of the tested mosquito pools were positive for WNV and USUV RNA. Phylogenetic analysis showed the circulation of WNV lineage 2 and Usutu Europe 2 lineage. Climate conditions in 2024 in Croatia were classified as extremely warm, which could, at least in part, impact the quite intense arboviral season. The spreading of flaviviruses in Croatia highlights the need for continuous surveillance in humans, animals, and vectors (“One Health”). Full article

Vector-borne diseases (VBDs) significantly impact global child health, with mosquito-transmitted infections like malaria and arboviruses accounting for a substantial portion of this burden. However, other arthropod-borne diseases—transmitted by vectors such as ticks, fleas, sand flies, lice, and triatomine bugs—also pose serious health risks to children worldwide. This review specifically excludes mosquito-borne diseases to concentrate on these less-discussed yet clinically important pediatric VBDs. We examine their clinical manifestations, diagnostic challenges, and treatment options, highlighting the unique vulnerabilities of children, including immature immune systems, behavioral factors, and communication barriers that can delay diagnosis. Additionally, we explore how environmental and anthropogenic factors, such as climate change and urbanization, are expanding the geographic range of these vectors, leading to the emergence of diseases like Lyme disease and leishmaniasis in new regions. By focusing on non-mosquito VBDs, this review aims to raise awareness and inform healthcare providers and public health practitioners about the comprehensive landscape of pediatric vector-borne diseases. Full article

The Aedes aegypti mosquito is a vector for several arboviral diseases, posing a significant threat to human populations and exacerbating health disparities. Puerto Rico is a subtropical region where A. aegypti mosquitoes circulate all the year promoting the transmission of arboviruses. A cross-sectional study in the municipality of Ponce, Puerto Rico was conducted to determine the prevalence of arbovirus in A. aegypti mosquitoes and community members, and the impact that sociodemographic and environmental factors on the presence of arbovirus in the community. Our results indicate that more than a third of the population has long-term antibodies (IgG) against chikungunya and the Mayaro virus (56% and 17%, respectively). In addition, more than two-thirds of the population have long-term antibodies (IgG) against dengue and Zika virus (96.0% and 77%, respectively). Dengue virus 1 (DENV-1) was only detected in mosquitoes from urban areas. The practice of storing water in containers uncovered and living near a river increased the odds of having arbovirus in the community (OR = 3.5, 95% CI = 1.8–10.6) (p < 0.05) and (OR = 1.6, 95% CI = 1.2–3.7). Furthermore, lower income was a social determinant associated with being at risk of arboviral disease in the communities (OR = 2.9, 95% CI = 1.4–8.5) (p < 0.05). It is recommended that public health activities be implemented, including education workshops on prevention and health promotion and health services such as vector control, to prevent arboviral diseases in communities. Full article

Aedes aegypti is the primary vector of arboviral diseases such as dengue, chikungunya, yellow fever, and Zika, posing significant global health and economic challenges. The effective control of this mosquito species requires understanding its seasonality, feeding behavior, and ecological dynamics. Modern molecular techniques, such as amplicon metagenomic sequencing, provide insights into vector–host interactions and feeding patterns. This study investigated the temporal variation of Ae. aegypti abundance and its blood meal sources in coastal and western Kenya over 16 months. A total of 64,360 mosquitoes were collected, with Ae. aegypti comprising 10.9% (7035/64,360). Coastal sites had a higher proportion (64.7%) of Ae. aegypti than western Kenya. Seasonal variation in abundance was observed, with peaks during the long rainy season and decline during the dry season. Blood meal analysis identified 15 vertebrate hosts, with humans being the primary source (86.6–95.9%). Other hosts included domestic animals such as turkey, sheep, cow, goat, and chicken. These findings highlight the role of rainfall in arboviral disease transmission and Ae. aegypti’s strong preference for human hosts. Additionally, this study demonstrates the cost-effectiveness of group testing for identifying blood meal sources, with implications for public health interventions. Full article

Following its initial documented emergence in Hunan’s swine facilities in 2017, GETV has inflicted considerable financial damage upon China’s pork production sector. Beyond its impact on swine, GETV also poses a potential risk to other animal species and public health, primarily due to its mosquito-borne transmission. Between September 2020 and May 2021, a GETV outbreak occurred on a commercial swine farm in Sichuan Province, where affected animals exhibited movement disorders, neurological symptoms, and mild diarrhea, with severe cases resulting in mortality. To elucidate the genetic characteristics and transmission dynamics of the virus, a comprehensive investigation of this outbreak was conducted. Clinical samples from diseased or deceased swine were collected and analyzed by PCR, confirming the presence of GETV infection. Additionally, differential diagnostic assays were performed for other common swine pathogens, including porcine reproductive and respiratory syndrome virus (PRRSV), pseudorabies virus (PRV), classical swine fever virus (CSFV), and atypical porcine pestivirus (APPV). All tests yielded negative results, confirming GETV as the sole etiological agent of the outbreak. The GETV-positive samples were inoculated into BHK-21 cells, leading to the isolation of a GETV strain (SC202009). Whole-genome sequence analysis revealed that SC202009 belongs to the GIII genotype of GETV, with a nucleotide sequence identity ranging from 95.1% to 99.8% compared to reference sequences in GenBank. This high level of sequence identity suggests that SC202009 is closely related to other circulating strains in the region, indicating potential local transmission networks and endemic viral circulation. The nucleotide sequence identity of the E2 gene ranged from 94.2% to 99.6%, while the E2 protein amino acid sequence identity ranged from 97.2% to 99.5%. Phylogenetic analysis further indicated that SC202009 is genetically distant from the original Malaysian prototype strain (MM2021) but shares high sequence identity with several strains isolated in Sichuan Province, including SC266, SC201807, and SC483. Notably, NMJA_F2_18-8L-NH-Cxp-Y-1-1 was isolated from Culex pipiens, suggesting a mosquito-borne transmission route. These findings provide novel insights into the regional dissemination patterns and genetic diversity of GETV in China. These results also highlight the importance of the continuous surveillance of viral genetic variations and the elucidation of transmission dynamics to develop effective control strategies and mitigate potential public health risks. Future studies should focus on the ecological and environmental factors influencing GETV transmission, particularly the role of mosquito vectors in cross-species viral spread, to enhance targeted prevention and control measures for this emerging arboviral threat. Full article

Despite the application of control measures, mosquito-borne diseases continue to pose a serious threat to human health. In this context, exploiting Wolbachia, a common symbiotic bacterium in insects, may offer effective solutions to suppress vectors or reduce their competence in transmitting several arboviruses. Many Wolbachia strains can induce conditional egg sterility, known as cytoplasmic incompatibility (CI), when infected males mate with females that do not harbor the same Wolbachia infection. Infected males can be mass-reared and then released to compete with wild males, reducing the likelihood of wild females encountering a fertile mate. Furthermore, certain Wolbachia strains can reduce the competence of mosquitoes to transmit several RNA viruses. Through CI, Wolbachia-infected individuals can spread within the population, leading to an increased frequency of mosquitoes with a reduced ability to transmit pathogens. Using artificial methods, Wolbachia can be horizontally transferred between species, allowing the establishment of various laboratory lines of mosquito vector species that, without any additional treatment, can produce sterilizing males or females with reduced vector competence, which can be used subsequently to replace wild populations. This manuscript reviews the current knowledge in this field, describing the different approaches and evaluating their efficacy, safety, and sustainability. Successes, challenges, and future perspectives are discussed in the context of the current spread of several arboviral diseases, the rise of insecticide resistance in mosquito populations, and the impact of climate change. In this context, we explore the necessity of coordinating efforts among all stakeholders to maximize disease control. We discuss how the involvement of diverse expertise—ranging from new biotechnologies to mechanistic modeling of eco-epidemiological interactions between hosts, vectors, Wolbachia, and pathogens—becomes increasingly crucial. This coordination is especially important in light of the added complexity introduced by Wolbachia and the ongoing challenges posed by global change. Full article

Brazil is one of the most important countries globally in regard to arboviral disease ecology and emergence or resurgence. Unfortunately, it has shouldered a majority of arboviral disease cases from Latin America and its rich flora, fauna (including arthropod vectors), and climate have contributed to the vast expansion of multiple arboviral diseases within its borders and those that have expanded geographically outside its borders. Anthropogenic landscape changes or human-mediated changes such as agriculture, deforestation, urbanization, etc. have all been at play within the country in various locations and can also be attributed to arboviral movement and resurgence. This review describes a brief history of landscape changes within the country and compiles all the known information on all arboviruses found within Brazil (endemic and imported) that are associated with human disease and mosquitoes including their original isolation, associated vertebrate animals, associated mosquitoes and other arthropods, and human disease symptomology presentations. This information is crucial as the Western Hemisphere is currently experiencing multiple arbovirus outbreaks, including one that originated in the Brazilian Amazon. Understanding which arboviruses are and have been circulating within the country will be pertinent as anthropogenic landscape changes are consistently being perpetrated throughout the country, and the occurrence of the next arbovirus epidemic will be a matter of when, not if. Full article

Aedes aegypti is a key vector in the transmission of arboviral diseases in the Colombian Amazon. This study aimed to characterize microbiota composition using DNA extracted from water in artificial breeding sites, immature stages, and adults of Ae. aegypti in Leticia, Amazonas. Additionally, the physicochemical water variables were correlated with the bacterial communities present. Eight artificial breeding sites were identified, with bucket, plant pot, and tire being the most frequent. The breeding sites exhibited similar physicochemical profiles, with significant temperature and salinity differences (p-value < 0.03). The most representative bacterial genera included Ottowia (82%), Xanthobacter (70.59%), and Rhodocyclaceae (92.78%) in breeding site water; Aquabacterium (61.07%), Dechloromonas (82.85%), and Flectobacillus (58.94%) in immature stages; and Elizabethkingia (70.89%) and Cedecea (39.19%) in males and females of Ae. aegypti. Beta diversity analysis revealed distinct clustering between adults and the water and immature communities (p-value < 0.001). Multivariate analysis showed strong correlations among bacterial communities, breeding sites, and physicochemical variables such as tire and drum cover which exhibited high levels of total dissolved solids, conductivity, and salinity associated with Flectobacillus, Leifsonia, Novosphingobium, Ottowia, and Rhodobacter. Bacterial genera such as Mycobacterium, Escherichia, Salmonella, and Clostridium, present in artificial breeding sites, are associated with public health relevance. This study provides insights into bacterial community dynamics across Ae. aegypti’s life cycle and underscores the importance of water physicochemical and biological characteristics for developing new vector control strategies. Full article

Dengue fever (DF), a leading arboviral disease globally, is caused by the Dengue virus (DENV) and represents a significant public health concern, with an estimated 390 million cases reported annually. Due to the complexity of the various dengue variants and the severity of the disease, vaccination emerges as the essential strategy for combating this widespread infectious disease. The absence of specific antiviral medications underscores the critical need for developing a Dengue vaccine. This review aims to present the current status and future prospects of Dengue vaccine development. Further, this review elaborates on the various strategies employed in vaccine development, including attenuated, inactivated, subunit, and viral vector vaccines. Each approach is evaluated based on its immunogenicity, safety, and efficacy, drawing on data from preclinical and clinical studies to highlight the strengths and limitations of each candidate vaccine. The current study sheds light on future directions and research priorities in developing Dengue vaccines. In conclusion, the development of a Dengue vaccine holds significant potential for reducing the global burden of DF. However, challenges remain in terms of vaccine safety, efficacy, delivery, and availability. Overcoming these challenges, coupled with advancements in vaccine technology, could lead to better control and prevention of Dengue, thereby enhancing public health and quality of life. Full article

Rift Valley fever (RVF) is a devastating zoonotic mosquito-borne viral hemorrhagic fever disease that threats human and animal health and biodiversity in Africa, including in Rwanda. RVF is increasingly outbreaking in Africa, leading to devastating impacts on health, socioeconomic stability and growth, and food insecurity in the region, particularly among livestock-dependent communi-ties. This systematic review synthesizes existing evidence on RVF’s epidemiology, transmission dynamics, and the prevention and control measures implemented in Rwanda. Our findings high-light the rapidly increasing prevalence of RVF and the expansion of its geographical distribution and host range in Rwanda. Furthermore, the review reveals gaps in local evidence, including the existence of competent vectors of RVFV and the risk factors associated with the emergence and spread of RVF in the country. This underscores the urgent need for prospective research to inform evidence-based health policymaking, strategic planning, and the development and implementation of cost-effective preventive and control measures, including diagnosis and surveillance for early detection and response. It also calls for the institutionalization of a cost-effective, multisectoral, and transdisciplinary One Health strategy for reducing the burden and risk of climate climate-sensitive and zoonotic diseases, including RVF, in the country. We recommend exploring cost-effective human and/or animal vaccination mechanisms for RVF, integrating AI-powered drones into dis-ease vectors surveillance and control, and the routine implementation of genomics-enhanced xenosurveillance to monitor changes in pathogens and vectors dynamics in order to inform poli-cymaking and guide the control interventions. Full article

Background: Vector-borne diseases, such as leishmaniasis and arboviral infections, represent a great challenge to human health with limited therapeutic options. In addition, sexually transmitted infections, such as herpes, affect billions of people worldwide and the emergence of new strains resistant to common antivirals, such as acyclovir (ACV), poses a serious threat to humans. In this context, coumarins have proved to be a valuable source of new derivatives with promising biological activities to fight these diseases. Methodology: 3-aryl and/or 4-(N-aryl)aminocoumarins were synthesized, and their drug-like profile was evaluated using silico tools. Their biological activity against Leishmania amazonensis promastigotes was evaluated using the MTT assay, while their antiviral activity against replication of Chikungunya, Mayaro, Zika, and type 1 Herpes simplex virus (HSV-1) in Vero cells was analyzed using plaque reduction assays. Results: The in silico studies pointed to satisfactory pharmacokinetic and toxicological properties as drug candidates. Hence, their antileishmanial activity was evaluated. None of the compounds exhibited significant activity and compound 2b showed the highest activity (IC₅₀ = 47.10 µM). We further evaluated their cytotoxicity and antiviral activity. Compound 2e showed good activity against ACV-sensitive and -resistant HSV-1 strains with EC₅₀ values of 48.68 µM and 66.26 µM, respectively (selectivity index values of 12.5 and 9.2). Mechanism of action studies indicated that this compound acts at late steps of HSV-1 replication, such as virus egress. Conclusions: Compound 2e possesses a different mechanism of action compared to ACV and presents a promising alternative for the treatment of HSV-1 infections. Full article

Viruses transmitted by arthropods (arboviruses) pose a global public health threat. Sporadic cases or outbreaks caused by West Nile virus, Crimean–Congo haemorrhagic fever virus, tick-borne encephalitis virus, and phleboviruses are often reported in Europe. Recently, they expanded their distribution in geographic areas where they had never been observed before, while tropical viruses, like Dengue, Chikungunya, and Zika, started to cause autochthonous cases and outbreaks following the return of viraemic travellers from endemic countries. The primary or secondary vectors of these viruses are established in Europe, and the incidence of arboviral diseases is expected to increase due to several anthropogenic and/or environmental factors (mainly climate change, which affects the survival and amplification of the arthropod vectors). This is an update on the emerging arboviruses in Europe, associated challenges, and future perspectives. Full article

Aedes aegypti is a major arboviral disease vector and is therefore a critical target for control by public health programs. Early eradication efforts have shown that Ae. aegypti can rapidly build insecticide resistance, and, now, resistance to pyrethroids, the major class of adulticides used for operational control, is common in many populations. A major contributor to this resistance is a group of knockdown resistance (kdr) SNPs that normally exist in distinct ensembles in the Western Hemisphere and the Indopacific with little known mixing. In this study, we detected, and confirmed, using multiple methods, the Indopacific kdr SNPs, both V1016G and S989P, in three recent collections from Osceola County, Florida. This represents a large expansion of the geographic range of the Indopacific kdr SNPs. We consider the implications of this finding on future insecticide resistance surveillance studies, including assessing the ability of our current screening tools to detect these SNPs. We find that the presence of the Indopacific SNPs requires the modification of existing resistance screening protocols and requires further work to understand the operational implications for mosquito control. Full article