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BACKGROUND: The burden of Aedes aegypti-transmitted viruses such as dengue, chikungunya, and Zika are increasing globally, fueled by urbanization and climate change, with some of the highest current rates of transmission in Asia. Local factors in the built environment have the potential to exacerbate or mitigate transmission. METHODS: In 24 informal urban settlements in Makassar, Indonesia and Suva, Fiji, we tested children under 5 years old for evidence of prior infection with dengue, chikungunya, and Zika viruses by IgG serology. We used a catalytic model using seroprevalence and mean age to estimate annual incidence of dengue in each country. We also conducted detailed questionnaires to evaluate environmental risk factors for a positive serology result. Dengue risk factors were evaluated for children by univariate and multivariable logistic regression accounting for settlement as a fixed effect. Trash and flooding were additionally evaluated as dengue risk factors at the settlement level by univariate linear regression. RESULTS: In Fiji and Indonesia respectively, 46% and 33% of children under 5 years old were seropositive for dengue, 3% and 3% for chikungunya, and 9% and 2% for Zika. In Indonesia, children living in a household where trash is routinely collected and removed were significantly less likely to be dengue seropositive in both unadjusted and adjusted models [adjusted model: OR 0.3 (95% CI: 0.1-0.8)]. In Indonesia, settlements with a higher proportion of households reporting flooding also had lower dengue rates (slope = 0.44; p-value:

ABSTRACT Background Aim Methods Results Conclusions West Nile virus (WNV) is the most widely distributed mosquito‐borne flavivirus. Over the past decade, its spread across Europe has raised significant concerns for both public and animal health. Although WNV exposure has been evidenced in various wild mammal species in Spain, no seroepidemiological studies have been conducted on this flavivirus in wild lagomorphs so far.This study aimed to assess WNV exposure in European wild rabbit (Oryctolagus cuniculus) and Iberian hare (Lepus granatensis) populations inhabiting Spanish Mediterranean ecosystems.Sera from 540 wild lagomorphs (399 European wild rabbit and 141 Iberian hares), from 106 hunting grounds distributed throughout Andalusia (southern Spain), were collected between the 2018/2019 and 2022/2023 hunting seasons.Antibodies against flavivirus were detected by blocking enzyme‐linked immunosorbent assay (bELISA) in 5.0% (27/540; 95% CI: 3.2–6.8) of the wild lagomorphs. Exposure to WNV was confirmed in 4.8% (19/394; 95% CI: 2.7–6.9) of wild rabbits and 0.7% (1/141; 95% CI: 0.0–2.1) of Iberian hares by virus microneutralisation test. Anti‐WNV antibodies were found in wild lagomorphs sampled from three (2.8%) hunting grounds located in western Andalusia during the seasons 2020–2021 and 2021–2022. Remarkably, this spatiotemporal distribution overlaps with the largest outbreak of WNV in Spain. Antibodies against Usutu virus and Bagaza virus were not detected in the wild lagomorph populations analysed.This study constitutes the first report of WNV exposure in wild rabbit in Spain and in Iberian hare worldwide. While these species seem not play a primary role in the epidemiology of the virus, they could serve as sentinel for monitoring WNV in Iberian Mediterranean ecosystems. [ABSTRACT FROM AUTHOR]

Background & objectives: Mosquito-bome diseases are increasing problems in various parts of the world, causing high mortality and morbidity for humans. This study was done to assess the vector protection measures taken by rural below poverty line (BPL) families, and to assess the awareness about vector-borne diseases along with Total Sanitation Campaign (TSC) in rural BPL families. Methods: A cross-sectional study was conducted in a rural area which won “Nirmal Gram Puraskar” Award i.e., “clean village” among 96 below BPL families for a period of three months. These families (every 5th) were selected by systematic random sampling until we reached a sample size. Basic socio-demographic details, status of vector protection measures, solid waste management, vector-borne diseases and total sanitation campaign details were collected from the study participants. Pretested, semi-structured questionnaire was applied to the head of the families which included sanitation status at home by house-to-house visit. Data collected was analysed using SPSS version 20 and presented as frequency, percentages, mean and standard deviation. Results: Among 96 families studied (454 adults and children), 84 (87.5%) were males and 12 (12.5%) were females. Among these, 291 (64.1%) were using one or the other mosquito protection measures, 52 (54.2%) were using bednets and 23 (23.9%) used coils. 12 families (12.5%) were not using any mosquito protection measures. In our study, 66 (68.8%) families had individual household latrine (IHHL) and 50 (52.1%) had open drainage. Even though 314 participants had an access to individual household latrine, 20 (6.36%) had practice of open air defecation compared to 127 (90.7%) who practiced open air defecation without an access to individual household latrine. When asked about the awareness regarding vector-borne diseases, 56 (58.3%) were aware about chikungunya, 47 (48.9%) about dengue, 46 (47.9%) about malaria, 14 (14.6%) and only 5 (5.2%) families were aware about Japanese encephalitis. In this study, 37 (38.5%) were aware about the total sanitation campaign and 40 (41.6%) about the government support for sanitation. Interpretation & conclusion: While there is a general awareness of vector-borne diseases, the implementation of vector protection measures is not uniform across the village. There is a need for targeted interventions to improve the effectiveness of vector protection measures and increase awareness among the community.

Climate change is an environmental problem that leads to extreme flood and drought events in various geographical regions. The review seeks to establish pertinent issues around changes in temperature and precipitation as climate factors which have been under-researched. It will be established whether the spread of disease and other human risks have been reported under various temperature and precipitation levels; whether sound adaptation measures are in place; communities are provided with awareness toward adaptation methods; and educated on how to deal with mental problems and anxiety caused by climate change. The review has established that little research has modeled variation in human characteristics like age group differences and health fluctuations with climate change, under a wide spectrum of temperature and precipitation. Southern African countries’ research also lacks projection of climate change impacts and risk distribution maps for vector borne diseases under RCP2.6, RCP4.4, RCP6.0 and RCP8.0. In addition, there has been bias in previous studies regarding a combination of temperature and precipitation, as well as non-climatic factors that may be favorable for spread and transmission of specified VBDs. Recommendations from this review could be adopted by countries in order to protect communities’ health. [ABSTRACT FROM AUTHOR]

Objective: Unknown etiology Background: West Nile virus (WNV) is a vector-borne flavivirus that is typically transmitted by Aedes and Anopheles mosquitos. WNV infection typically presents with symptoms consistent with viral meningitis, which include fever, headache, and meningeal signs. WNV infections are typically self-resolving, with symptoms lasting 3-10 days. Although uncommon, patients with WNV infection can be afflicted with hyponatremia, although the etiology is unclear. Because of encephalitis, neuroinflammation may be involved in the deterioration of adrenal signaling, leading to salt wasting. Case Report: We present the case of a 75-year-old man who presented with headache, neck pain, photophobia, and viral illness symptoms. He was found to be profoundly hyponatremic, concerning for SIADH. He had a sodium drop to 117 mmol/L, leading to further lethargy and confusion. He received 3% saline, fluid restriction, and salt tablets, and more common causes of SIADH were ruled out. MRI revealed the absence of the posterior pituitary bright spot. He was subsequently found to have positive WNV titers and improved with continued supportive treatment. Conclusions: WNV presents a unique challenge to providers due to its difficult diagnosis and association with hyponatremia. There is no clear role for specific medical treatment such as corticosteroids vs IV immunoglobulins. Supportive care is recommended for those testing positive for WNV. Clinicians should consider the possibility of viral infections, such as WNV, in patients living in endemic areas who present with unexplained hyponatremia, cognitive symptoms, and relevant history. [ABSTRACT FROM AUTHOR]

Tick-borne pathogens pose a significant global threat, causing substantial economic losses to the dairy industry. In India, tropical theileriosis, anaplasmosis, babesiosis, and trypanosomiasis are major hemo-parasitic diseases affecting bovines. A cross-sectional study was conducted to determine the prevalence of hemo-parasites in different farms in India. PCR assays were employed to detect carrier status, using gene targets msp1b, tams1, rap-1, ama1, and ITS1 for A. marginale, T. annulata, B. bovis, B. bigemina, and Trypanosoma species, respectively. Out of the 578 apparently healthy animals screened, 30.45% (95% CI: 26.84–34.32%) were infected with at least one hemo-parasite. Cattle showed an overall positivity of 32.87%, while buffaloes had a prevalence of 15.19%, which was statistically significant (p < 0.001). Interestingly, prevalence was higher in indigenous cattle (47.81%) compared to cross-breeds (25.53%) and exotics (14.62%), with a statistically significant difference (p < 0.001). The prevalence of hemo-parasites varied widely among the farms, ranging from 5.77 to 100%. A. marginale was the most prevalent parasite (23.70% of animals), followed by T. annulata (13.67%), Babesia species (1.90%), and Trypanosoma species (1.56%). Enzootic instability was observed in six of the eight farms, indicating a potential for future outbreaks. Co-infection was detected in 60 out of 176 animals positive for hemo-parasites, with 59 animals co-infected with A. marginale and T. annulata, and only one cross-breed cattle infected with both Anaplasma marginale and Babesia bigemina. The findings highlight the prevalence of hemo-parasites in farms, underscoring the need for whole-herd screening, treatment of infected animals, and improvement in farm management practices to prevent production losses caused by these pathogens. [ABSTRACT FROM AUTHOR]

Abstract Background Malaria, a prominent vector borne disease causing over a million annual cases worldwide, predominantly affects vulnerable populations in the least developed regions. Despite their preventable and treatable nature, malaria remains a global public health concern. In the last decade, India has faced a significant decline in malaria morbidity and mortality. As India pledged to eliminate malaria by 2030, this study examined a decade of surveillance data to uncover space–time clustering and seasonal trends of Plasmodium vivax and Plasmodium falciparum malaria cases in West Bengal. Methods Seasonal and trend decomposition using Loess (STL) was applied to detect seasonal trend and anomaly of the time series. Univariate and multivariate space–time cluster analysis of both malaria cases were performed at block level using Kulldorff’s space–time scan statistics from April 2011 to March 2021 to detect statistically significant space–time clusters. Results From the time series decomposition, a clear seasonal pattern is visible for both malaria cases. Statistical analysis indicated considerable high-risk P. vivax clusters, particularly in the northern, central, and lower Gangetic areas. Whereas, P. falciparum was concentrated in the western region with a significant recent transmission towards the lower Gangetic plain. From the multivariate space–time scan statistics, the co-occurrence of both cases were detected with four significant clusters, which signifies the regions experiencing a greater burden of malaria cases. Conclusions Seasonal trends from the time series decomposition analysis show a gradual decline for both P. vivax and P. falciparum cases in West Bengal. The space–time scan statistics identified high-risk blocks for P. vivax and P. falciparum malaria and its co-occurrence. Both malaria types exhibit significant spatiotemporal variations over the study area. Identifying emerging high-risk areas of P. falciparum malaria over the Gangetic belt indicates the need for more research for its spatial shifting. Addressing the drivers of malaria transmission in these diverse clusters demands regional cooperation and strategic strategies, crucial steps towards overcoming the final obstacles in malaria eradication.

Background: Malaria, a prominent vector borne disease causing over a million annual cases worldwide, predominantly affects vulnerable populations in the least developed regions. Despite their preventable and treatable nature, malaria remains a global public health concern. In the last decade, India has faced a significant decline in malaria morbidity and mortality. As India pledged to eliminate malaria by 2030, this study examined a decade of surveillance data to uncover space–time clustering and seasonal trends of Plasmodium vivax and Plasmodium falciparum malaria cases in West Bengal. Methods: Seasonal and trend decomposition using Loess (STL) was applied to detect seasonal trend and anomaly of the time series. Univariate and multivariate space–time cluster analysis of both malaria cases were performed at block level using Kulldorff's space–time scan statistics from April 2011 to March 2021 to detect statistically significant space–time clusters. Results: From the time series decomposition, a clear seasonal pattern is visible for both malaria cases. Statistical analysis indicated considerable high-risk P. vivax clusters, particularly in the northern, central, and lower Gangetic areas. Whereas, P. falciparum was concentrated in the western region with a significant recent transmission towards the lower Gangetic plain. From the multivariate space–time scan statistics, the co-occurrence of both cases were detected with four significant clusters, which signifies the regions experiencing a greater burden of malaria cases. Conclusions: Seasonal trends from the time series decomposition analysis show a gradual decline for both P. vivax and P. falciparum cases in West Bengal. The space–time scan statistics identified high-risk blocks for P. vivax and P. falciparum malaria and its co-occurrence. Both malaria types exhibit significant spatiotemporal variations over the study area. Identifying emerging high-risk areas of P. falciparum malaria over the Gangetic belt indicates the need for more research for its spatial shifting. Addressing the drivers of malaria transmission in these diverse clusters demands regional cooperation and strategic strategies, crucial steps towards overcoming the final obstacles in malaria eradication. [ABSTRACT FROM AUTHOR]

Aedes aegypti mosquitos are the primary vector for dengue, chikungunya, and Zika viruses and tend to breed in small containers of water, with a propensity to breed in small piles of trash and abandoned tires. This study piloted the use of aerial imaging to map and classify potential Ae. aegypti breeding sites with a specific focus on trash, including discarded tires. Aerial images of coastal and inland sites in Kenya were obtained using an unmanned aerial vehicle. Aerial images were reviewed for identification of trash and suspected trash mimics, followed by extensive community walk-throughs to identify trash types and mimics by description and ground photography. An expert panel reviewed aerial images and ground photos to develop a classification scheme and evaluate the advantages and disadvantages of aerial imaging versus walk-through trash mapping. A trash classification scheme was created based on trash density, surface area, potential for frequent disturbance, and overall likelihood of being a productive Ae. aegypti breeding site. Aerial imaging offers a novel strategy to characterize, map, and quantify trash at risk of promoting Ae. aegypti proliferation, generating opportunities for further research on trash associations with disease and trash interventions. [ABSTRACT FROM AUTHOR]

Throughout history, vector-borne diseases have consistently posed significant challenges to human health. Among the strategies for vector control, chemical insecticides have seen widespread use since their inception. Nevertheless, their effectiveness is continually undermined by the steady growth of insecticide resistance within these vector populations. As such, the demand for more robust, efficient, and cost-effective natural insecticides has become increasingly pressing. One promising avenue of research focuses on chitin, a crucial structural component of mosquitoes' exoskeletons and other insects. Chitin not only provides protection and rigidity but also lends flexibility to the insect body. It undergoes substantial transformations during insect molting, a process known as ecdysis. Crucially, the production of chitin is facilitated by an enzyme known as chitin synthase, making it an attractive target for potential novel insecticides. Our recent study delved into the impacts of curcumin, a natural derivative of turmeric, on chitin synthesis and larval development in Aedes aegypti, a mosquito species known to transmit dengue and yellow fever. Our findings demonstrate that even sub-lethal amounts of curcumin can significantly reduce overall chitin content and disrupt the cuticle development in the 4th instar larvae of Aedes aegypti. Further to this, we utilized computational analyses to investigate how curcumin interacts with chitin synthase. Techniques such as molecular docking, pharmacophore feature mapping, and molecular dynamics (MD) simulations helped to illustrate that curcumin binds to the same site as polyoxin D, a recognized inhibitor of chitin synthase. These findings point to curcumin's potential as a natural, bioactive larvicide that targets chitin synthase in mosquitoes and potentially other insects. [ABSTRACT FROM AUTHOR]

Abstract Habronemosis, also known as habronemiasis or habronematidosis, is a parasitic disease of equids caused by the larval stages of Habronematidae nematodes (Habronema muscae, Habronema microstoma, and Draschia megastoma) that are transmitted by muscid flies. The presence of aberrant infective larvae in the cutaneous and conjunctival tissues of these hosts results in granulomatous, exudative, and ulcerated lesions, also known as “summer sores.” In this study, we present a retrospective analysis of habronemosis cases in horses from the municipality of Lages, located on the Santa Catarina Plateau, a region with high altitudes and a temperate climate that differs from regions of Brazil where such parasitosis usually occurs. The equids were examined from 2008 to 2020 at the Veterinary Hospital of Santa Catarina State University. Sixteen patients were diagnosed and treated using macrocyclic lactones and wound cleaning. Most cases were recorded in autumn in horses (10/16, 62.5%) over 15 years of age (11/16, 68.8%), and the lesions were more frequently located in the conjunctiva (11/16, 68.8%). In scientific dissemination media, this is the first report of habronemosis on the Santa Catarina Plateau, Brazil. This information will contribute to the diagnosis, treatment and prevention of skin diseases in horses in this region.

Mosquito transgenesis and gene-drive technologies provide the basis for developing promising new tools for vector-borne disease prevention by either suppressing wild mosquito populations or reducing their capacity from transmitting pathogens. Many studies of the regulatory DNA and promoters of genes with robust sex-, tissue- and stage-specific expression profiles have supported the development of new tools and strategies that could bring mosquito-borne diseases under control. Although the list of regulatory elements available is significant, only a limited set of those can reliably drive spatial-temporal expression. Here, we review the advances in our ability to express beneficial and other genes in mosquitoes, and highlight the information needed for the development of new mosquito-control and anti-disease strategies.

Dengue is a growing global public health challenge, with rising incidence and case fatality rates fueled by urbanization and climate change. The substantial mortality, morbidity, and economic burden associated with the disease underscore the need for effective prevention strategies, including vector control, personal protective measures, and vaccination. This narrative review provides a practical guide for clinicians to ensure the appropriate administration of dengue vaccines to at-risk groups, such as individuals in endemic regions and travelers to these areas. Live-attenuated tetravalent dengue vaccines, including Dengvaxia®, Qdenga®, and Butantan-DV, have demonstrated efficacy in clinical trials but require careful use due to the risk of antibody-dependent enhancement (ADE). To mitigate this risk, guidelines recommend vaccination primarily for individuals with prior confirmed dengue infection, emphasizing the importance of accessible and affordable point-of-care rapid testing. Co-administration of dengue vaccines with other live-attenuated or inactivated vaccines has been shown to be safe and immunogenic, broadening their potential application. However, live-attenuated vaccines are contraindicated for immunocompromised individuals and pregnant women. Enhancing clinician awareness, expanding diagnostic capabilities, and prioritizing high-risk populations are critical steps to optimize vaccination strategies. Combined with robust prevention programs, these efforts are essential to reducing the global burden of dengue and mitigating its impact.

Aims: West Nile Virus (WNV) has remained a persistent source of vector‐borne disease risk in California since first being identified in the state in 2003. The geographic distribution of WNV activity is relatively widespread, but varies considerably across different regions within the state. Spatial variation in human WNV infection depends upon social‐ecological factors that influence mosquito populations and virus transmission dynamics. Measuring changes in spatial patterns over time is necessary for uncovering the underlying regional drivers of disease risk. Methods and Results: In this study, we utilized statewide surveillance data to quantify temporal changes and spatial patterns of WNV activity in California. We obtained annual WNV mosquito surveillance data from 2004 through 2021 from the California Arbovirus Surveillance Program. Geographic coordinates for mosquito pools were analysed using a suite of spatial statistics to identify and classify patterns in WNV activity over time. Conclusions: We detected clear patterns of non‐random WNV risk during the study period, including emerging hot spots in the Central Valley and non‐random periods of oscillating WNV risk in Southern and Northern California subregions. Our findings offer new insights into 18 years of spatio‐temporal variation in WNV activity across California, which may be used for targeted surveillance efforts and public health interventions. [ABSTRACT FROM AUTHOR]

Introduction: Mosquito-borne diseases represent a global public health concern and are responsible for over 700 000 deaths globally every year. Additionally, many mosquito species have undergone a dramatic global expansion due to various factors, including climate change, and forecasts indicate that mosquito populations will persist in dispersing beyond their present geographic range, namely in temperate climates. The research literature on this topic has grown in recent years, including some systematic evidence synthesis. However, to provide a comprehensive overview of this growing literature needed for policy action, a summary of this evidence, including existing systematic reviews, is required. This study aims to undertake an umbrella review that explores the impacts of climate change on the emergence and reemergence of diseases transmitted by mosquitoes in temperate zones and the publication of the protocol is a fundamental step to ensure the credibility, transparency and reproducibility of this research. Methods and Analysis: Studies published in scientific journals indexed by PubMed, EMBASE, Cochrane Library, Epistemonikos, and Web of Science Core Collection to be included in this umbrella review will meet the following criteria: the topic of study (climate change and mosquito-borne diseases), regions (temperate zones), study designs (systematic reviews and meta-analysis), language (any) and date (since inception until December 31st, 2023). Titles and abstracts from selected articles will be evaluated by two authors independently and any discrepancy will be resolved through consensus or, if not possible, through a third author. The data will be extracted, and the risk of bias will be evaluated. The quality of the methodology of the included reviews will be assessed using AMSTAR 2. A narrative synthesis will examine the included systematic reviews. The quality of evidence for all outcomes will be judged using the Grading of Recommendations Assessment, Development and Evaluation working group methodology.

Over half the world's population is at risk for viruses transmitted by Aedes mosquitoes, such as dengue and Zika. The primary vector, Aedes aegypti, thrives in urban environments. Despite decades of effort, cases and geographic range of Aedes-borne viruses (ABVs) continue to expand. Rigorously proven vector control interventions that measure protective efficacy against ABV diseases are limited to Wolbachia in a single trial in Indonesia and do not include any chemical intervention. Spatial repellents, a new option for efficient deployment, are designed to decrease human exposure to ABVs by releasing active ingredients into the air that disrupt mosquito-human contact. A parallel, cluster-randomized controlled trial was conducted in Iquitos, Peru, to quantify the impact of a transfluthrin-based spatial repellent on human ABV infection. From 2,907 households across 26 clusters (13 per arm), 1,578 participants were assessed for seroconversion (primary endpoint) by survival analysis. Incidence of acute disease was calculated among 16,683 participants (secondary endpoint). Adult mosquito collections were conducted to compare Ae. aegypti abundance, blood-fed rate, and parity status through mixed-effect difference-in-difference analyses. The spatial repellent significantly reduced ABV infection by 34.1% (one-sided 95% CI lower limit, 6.9%; one-sided P value = 0.0236, z = 1.98). Aedes aegypti abundance and blood-fed rates were significantly reduced by 28.6 (95% CI 24.1%, ∞); z = -9.11) and 12.4% (95% CI 4.2%, ∞); z = -2.43), respectively. Our trial provides conclusive statistical evidence from an appropriately powered, preplanned cluster-randomized controlled clinical trial of the impact of a chemical intervention, in this case a spatial repellent, to reduce the risk of ABV transmission compared to a placebo.

Background: Malaria infection is associated with many adverse outcomes for pregnant women and neonates, yet pregnant women in East and Southern Africa remain frequently exposed to malaria. Long-lasting insecticidal nets (LLINs) can help prevent malarial infections and the associated adverse events. The Hati Salama (HASA) study was a cluster-randomized controlled trial implemented in 100 antenatal health facilities in urban and rural settings of Tanzania that provided pregnant women in both intervention and control groups with e-vouchers to redeem for LLINs for malaria prevention. The intervention group received behavior change communication mobile messages across a 14-day period while the e-voucher was active, and no significant difference between the rates of e-voucher redemption was found across the two groups. Objective: This study was a process evaluation of the HASA randomized controlled trial to determine barriers and facilitators to e-voucher reception and LLIN acquisition for pregnant women enrolled in the trial, as well as challenges and lessons learned by nurses who worked at the antenatal health facilities supporting the trial. Methods: Following the e-voucher's expiration at 14 days, voluntary phone follow-up surveys were conducted for nurses who supported the trial, as well as participants in both intervention and control groups of the trial who did not redeem their e-vouchers. Survey questions asked nurses about workflow, training sessions, network connectivity, proxy phone use, and more. Surveys asked participants about reasons for not redeeming e-vouchers. Both surveys provided lists of preset answers to questions, as well as the option to provide open-ended responses. Nurses and trial participants were contacted between January and June 2016 on up to three occasions. Results: While nurses who supported the HASA trial seemed to recognize the value of the program in their communities, some barriers identified by nurses included network connectivity, workload increase, inadequate training and on-the-ground support, and difficulty following the workflow. Several barriers identified by trial participants included personal obligations preventing them from redeeming the e-voucher on time, network connectivity issues, losing the e-voucher number, no stock of LLINs at retailers when attended, inadequate explanation of where or how to redeem the e-voucher, or not receiving an SMS text message with the e-voucher number promptly or at all. Conclusions: Large-scale e-voucher platforms for health-related commodity interventions, such as LLIN distribution in sub-Saharan Africa, are feasible, but challenges, including network connectivity, must be addressed. Nurses identified issues to be considered in a future scale-up, such that the number of nurses trained should be increased and the e-voucher issuance workflow should be simplified. To address some of the key barriers impacting e-voucher redemption for trial participants, the network of retailers could be expanded and the e-voucher expiration period should be extended. Trial Registration: ClinicalTrials.gov NCT02561624; https://clinicaltrials.gov/ct2/show/NCT02561624 [ABSTRACT FROM AUTHOR]

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Mosquito-borne diseases, such as dengue and malaria, pose significant global health burdens. Unfortunately, current control methods based on insecticides and environmental maintenance have fallen short of eliminating the disease burden. Scalable, deployable, genetic-based solutions are sought to reduce the transmission risk of these diseases. Pathogen-blocking Wolbachia bacteria, or genome engineering-based mosquito control strategies including gene drives have been developed to address these problems, both requiring the release of modified mosquitoes into the environment. Here, we review the latest developments, notable similarities, and critical distinctions between these promising technologies and discuss their future applications for mosquito-borne disease control.

Background: Scientific overwhelming evidence confirms that the prevalence and incidence of mosquito-borne viruses such as chikungunya (CHIK) are dramatically increasing in Middle- Eastern countries including Iran.Methods: I n t his r eview a rticle, u sing r elevant k eywords (“Chikungunya” OR “CHIKV” OR “Aedes albopictus” OR “Aedes aegypti”), available literature was searched to collect data related to the reports of CHIK and its main vectors, Aedes albopictus and Ae. aegypti, in Iran and 15 neighboring countries: Pakistan, Afghanistan, Turkmenistan, Russia, Azerbaijan, Armenia, Turkey, Iraq, Kuwait, Bahrain, Qatar, United Arab Emirates (UAE), Oman, Saudi Arabia, and Yemen.Results: CHIK was reported in neighboring countries such as Pakistan, Turkey, Russia, Saudi Arabia, Yemen, Oman, Qatar, and Iraq. Furthermore, presumably introduced in 2019, CHIK was reported in 11 provinces in Iran with overall seropositivity of 17.23% in humans over the past three years. The mosquitoes, Ae. albopictus and Ae. aegypti, have recently been reported in the southeast and south of Iran.Conclusion: Given the change in climate, even if the density of the vectors is still limited, there is no guarantee that their population will not spread much more in the coming years. This emphasizes the urgent need to strengthen the surveillance system for the vectors, and sustained surveillance of CHIK infections in mosquitoes and humans, preferably in a collaborative international project.

Objective. To assess how relevant the flow of people between communities is, compared to vaccination and type of vector, on the spread and potential outbreaks of yellow fever in a disease-free host community. Methods. Using a SEIRV-SEI model for humans and vectors, we applied numerical simulations to the scenarios: (1) migration from an endemic community to a disease-free host community, comparing the performance of Haemagogus janthinomys and Aedes aegypti as vectors; (2) migration through a transit community located on a migratory route, where the disease is endemic, to a disease-free one; and (3) effects of different vaccination rates in the host community, considering the vaccination of migrants upon arrival. Results. Results show no remarkable differences between scenarios 1 and 2. The type of vector and vaccination coverage in the host community are more relevant for the occurrence of outbreaks than migration rates, with H. janthinomys being more effective than A. aegypti. Conclusions. With vaccination being more determinant for a potential outbreak than migration rates, vaccinating migrants on arrival may be one of the most effective measures against yellow fever. Furthermore, H. janthinomys is a more competent vector than A. aegypti at similar densities, but the presence of A. aegypti is a warning to maintain vaccination above recommended levels.

Vector-borne diseases (VBDs) are embedded within complex socio-ecological systems. While research has traditionally focused on the direct effects of VBDs on human morbidity and mortality, it is increasingly clear that their impacts are much more pervasive. VBDs are dynamically linked to feedbacks between environmental conditions, vector ecology, disease burden, and societal responses that drive transmission. As a result, VBDs have had profound influence on human history. Mechanisms include: (1) killing or debilitating large numbers of people, with demographic and population-level impacts; (2) differentially affecting populations based on prior history of disease exposure, immunity, and resistance; (3) being weaponised to promote or justify hierarchies of power, colonialism, racism, classism and sexism; (4) catalysing changes in ideas, institutions, infrastructure, technologies and social practices in efforts to control disease outbreaks; and (5) changing human relationships with the land and environment. We use historical and archaeological evidence interpreted through an ecological lens to illustrate how VBDs have shaped society and culture, focusing on case studies from four pertinent VBDs: plague, malaria, yellow fever and trypanosomiasis. By comparing across diseases, time periods and geographies, we highlight the enormous scope and variety of mechanisms by which VBDs have influenced human history.

Toscana virus (TOSV) is an emerging cause of central nervous system (CNS) infections, especially in endemic countries during summer. Cerebrospinal fluid (CSF) is usually clear, with 60 % serum glucose) and normal (< 45 mg/dL) to slightly increased protein levels. Here we present two cases of TOSV meningitis with misleading CSF characteristics observed at Santa Maria Annunziata Hospital (Bagno a Ripoli, Florence, Italy). Case 1 presented with signs and symptoms of meningitis. CSF was opalescent on macroscopic examination, with 1192 cells/mm3, hypoglycorrhachia (30 % serum glucose) and hyperproteinorachia (228.0 mg/dL). TOSV meningitis was confirmed with serology. Case 2 presented with headache, vomiting and mild neck stiffness. CSF was slightly turbid, with 1092 cells/mm3, normal glucose (61 % serum glucose) and slightly increased protein (77.0 mg/dL) levels. TOSV meningitis was confirmed with serology and molecular test on CSF. We performed a literature review including cases of TOSV neuroinvasive infections in which CSF characteristics were reported. Pleocytosis > 500 cells/mm3 was reported in 12/62 (19.4 %) patients, hypoglycorrhachia in 3/62 (4.8 %) patients, mild hyperproteinorachia (45 - 75 mg/dL) in 7/62 (11.3 %) patients and severe hyperproteinorachia (> 75 mg/dL) in 40/62 (64.5 %) patients. TOSV should be considered in the differential diagnosis of CNS infections in endemic areas during the warm season even when CSF examination shows atypical results.

ObjectivesThe protracted and violent conflict in Syria has resulted in large-scale displacement of people and destruction of health and sanitation infrastructure. The aim of this study was to examine epidemiological trends in vector-borne disease (VBD) outbreaks before and following the onset of the Syrian conflict (2011).MethodsProMED, a digital disease surveillance tool, was queried for VBD outbreak reports affecting humans and animals in Syria and select bordering countries between 2003 and 2018. Data were normalized by dividing the number of unique VBD events by the total number of unique outbreak events reported by ProMED for each year. Suspected and confirmed case counts and deaths were manually extracted.ResultsReports on VBDs increased from a mean of 2.9/year pre-2011 to 12.8/year post-2011, a 343.5% (p < 0.05) increase. After normalization, reports increased by 485.5% (p < 0.05) over the time periods. Post-2011, the most commonly reported VBDs were leishmaniasis, Crimean-Congo hemorrhagic fever, and lumpy skin disease. Reported numbers of suspected and confirmed cases and deaths increased during the conflict period.ConclusionsVBD outbreak events in ProMED increased in Syria and select bordering countries after the onset of the Syrian conflict in 2011. Enhanced disease surveillance is critical to detect and manage outbreaks in conflict settings.

Interest in gene drive technology has continued to grow as promising new drive systems have been developed in the lab and discussions are moving towards implementing field trials. The prospect of field trials requires models that incorporate a significant degree of ecological detail, including parameters that change over time in response to environmental data such as temperature and rainfall, leading to seasonal patterns in mosquito population density. Epidemiological outcomes are also of growing importance, as: i) the suitability of a gene drive construct for release will depend on its expected impact on disease transmission, and ii) initial field trials are expected to have a measured entomological outcome and a modeled epidemiological outcome. We present MGDrivE 2 (Mosquito Gene Drive Explorer 2): a significant development from the MGDrivE 1 simulation framework that investigates the population dynamics of a variety of gene drive architectures and their spread through spatially-explicit mosquito populations. Key strengths and fundamental improvements of the MGDrivE 2 framework are: i) the ability of parameters to vary with time and induce seasonal population dynamics, ii) an epidemiological module accommodating reciprocal pathogen transmission between humans and mosquitoes, and iii) an implementation framework based on stochastic Petri nets that enables efficient model formulation and flexible implementation. Example MGDrivE 2 simulations are presented to demonstrate the application of the framework to a CRISPR-based split gene drive system intended to drive a disease-refractory gene into a population in a confinable and reversible manner, incorporating time-varying temperature and rainfall data. The simulations also evaluate impact on human disease incidence and prevalence. Further documentation and use examples are provided in vignettes at the project's CRAN repository. MGDrivE 2 is freely available as an open-source R package on CRAN (https://CRAN.R-project.org/package=MGDrivE2). We intend the package to provide a flexible tool capable of modeling gene drive constructs as they move closer to field application and to infer their expected impact on disease transmission.

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Vector-borne diseases, transmitted by blood-feeding arthropods like mosquitoes, ticks, and fleas, pose an escalating challenge to global public health. Dengue, a disease propagated by Aedes mosquitoes, is currently the most rapidly spreading vector-borne illness worldwide. Given its endemic nature, the prevention and control of outbreaks remain a global imperative. Timely detection of dengue is critical to mitigate mortality rates, making predictive models indispensable tools for public health planning, resource allocation, and disease control. This study undertakes a comprehensive review of various machine learning algorithms used in developing predictive models for early-stage dengue detection based on presented symptoms. The review encompasses the entire modeling process, including data preprocessing, algorithm implementation, evaluation, and validation. It further delves into the algorithms' ability to accurately classify dengue into febrile, critical, or convalescent phases. An array of machine learning algorithms, including Logistic Regression, K-Nearest Neighbor, Support Vector Machine (SVM), Decision Tree, Artificial Neural Network, and Naive Bayes Classifier were analyzed. The advantages and disadvantages of these algorithms are discussed to identify the most effective approach for dengue prediction. The Naive Bayes algorithm was found to quickly generate predictions with a precision value of 99.1%. However, the SVM model outperformed all others with a cross-validation score of 98.5%, K-Fold validation of 97.5%, precision of 98.2%, and an F1 Score of 98.0%, thereby enhancing the overall performance of the predictive model. [ABSTRACT FROM AUTHOR]

Purpose of reviewVaccine-preventable diseases remain a major public health concern globally. Climate is a key driver of the dynamics of many infectious diseases, including those that are vaccine preventable. Understanding the impact of climate change on vaccine-preventable diseases is, thus, an important public health research priority. Here, we summarize the recent literature and highlight promising directions for future research.Recent findingsVaccine-preventable enteric diseases, such as cholera, exhibit sensitivity to precipitation and flooding events. The predicted increase in extreme weather events as a result of climate change could exacerbate outbreaks of these pathogens. For airborne pathogens, temperature and specific humidity have been shown to be the most important environmental drivers, although the impact of climate change on disease burden and dynamics remains unclear. Finally, the transmission dynamics of vector-borne diseases are dependent on both temperature and precipitation, and climate change is expected to alter the burden and geographic range of these diseases. However, understanding the interacting effects of multiple factors, including socioeconomic and ecological factors, on the vector-borne disease ecosystem will be a crucial step towards forecasting disease burden under climate change. Recent work has demonstrated associations between climate and transmission of vaccine-preventable diseases. Translating these findings into forecasts under various climate change scenarios will require mechanistic frameworks that account for both intrinsic and extrinsic drivers of transmission, and the non-linear effects on disease burden. Future research should also pay greater attention to uncertainty in both the climate modeling processes as well as disease outcomes in the context of vaccine-preventable diseases.

BackgroundMosquitoes are vectors of many tropical diseases. Understanding the ecology of local mosquito vectors, such as species composition, distributions, population dynamics, and species diversity is important for designing the optimal strategy to control the mosquito-borne diseases.MethodsEntomological surveillance of adult mosquitoes was conducted in five sites representing different ecological settings across Hainan Island from January to December of 2018 using BG Sentinel (BGS) traps and Centers for Disease Prevention and Control (CDC) light traps. In each site, we selected three areas representing urban, suburban and rural settings. Eighteen trap-days were sampled in each setting at each site, and CDC light traps and BGS traps were setup simultaneously. Mosquito species composition, distribution, population dynamics, and species diversity were analyzed. Mosquito densities were compared between different study sites and between different settings.ResultsNine species of mosquitoes belonging to four genera were identified. Culex quinquefasciatus (80.8%), Armigeres subalbatus (13.0%) and Anopheles sinensis (3.1%) were the top three species collected by CDC light traps; Cx. quinquefasciatus (91.9%), Ae. albopictus (5.1%), and Ar. subalbatus (2.8%) were the top three species collected by BGS traps. Predominant species varied among study sites. The population dynamics of Ae. albopictus, An. sinensis and Cx. quinquefasciatus showed clear seasonal variation regardless of study sites with a varied peak season for different species. Mosquito abundance of all species showed significant differences among different study sites and among urban, suburban and rural areas. Danzhou had the highest mosquito biodiversity, with an α, β, and Gini-Simpson biodiversity index of 8, 1.13 and 0.42, respectively. BGS traps captured Aedes mosquito at a higher efficiency than CDC light traps, whereas CDC light traps captured significantly more Anopheles and Armigeres mosquitoes than BGS traps.ConclusionsMosquitoes were abundant on Hainan Island with clear seasonality and spatial heterogeneity. Population density, species composition, distribution, and species diversity were strongly affected by the natural environment. Different tools are required for the surveillance of different mosquito species.

Vector-borne plant diseases have significant ecological and economic impacts, affecting farm profitability and forest composition throughout the world. Bacterial vector-borne pathogens have evolved sophisticated strategies to interact with their hemipteran insect vectors and plant hosts. These pathogens reside in plant vascular tissue, and their study represents an excellent opportunity to uncover novel biological mechanisms regulating intracellular pathogenesis and to contribute to the control of some of the world's most invasive emerging diseases. In this perspective, we highlight recent advances and major unanswered questions in the realm of bacterial vector-borne disease, focusing on liberibacters, phytoplasmas, spiroplasmas, and Xylella fastidiosa.

A thorough understanding of malaria vector species composition and their bionomic characteristics is crucial to devise effective and efficient vector control interventions to reduce malaria transmission. It has been well documented in Africa that malaria interventions in the past decade have resulted in major changes in species composition from endophilic Anopheles gambiae to exophilic An. arabiensis. However, the role of cryptic rare mosquito species in malaria transmission is not well known. This study examined the species composition and distribution, with a particular focus on malaria transmission potential of novel, uncharacterized Anopheles cryptic species in western Kenya. Phylogenetic analysis based on ITS2 and COX1 genes revealed 21 Anopheles mosquito species, including two previously unreported novel species. Unusually high rates of Plasmodium sporozoite infections were detected in An. funestus, An. gambiae and eight cryptic rare species. Plasmodium falciparum, P. malariae and P. ovale sporozoite infections were identified with large proportion of mixed species infections in these vectors. This study, for the first time, reports extensive new Anopheles cryptic species involved in the malaria transmission in western Kenya. These findings underscore the importance of non-common Anopheles species in malaria transmission and the need to target them in routine vector control and surveillance efforts.

Vector-borne diseases are emerging at an increasing rate and comprise a disproportionate share of all emerging infectious diseases. Yet, the key ecological and evolutionary dimensions of vector-borne disease that facilitate their emergence have not been thoroughly explored. This study reviews and synthesizes the existing literature to explore global patterns of emerging vector-borne zoonotic diseases (VBZDs) under changing global conditions. We find that the vast majority of emerging VBZDs are transmitted by ticks (Ixodidae) and mosquitoes (Culicidae) and the pathogens transmitted are dominated by Rickettsiaceae bacteria and RNA viruses (Flaviviridae, Bunyaviridae, and Togaviridae). The most common potential driver of these emerging zoonoses is land use change, but for many diseases, the driver is unknown, revealing a critical research gap. While most reported VBZDs are emerging in the northern latitudes, after correcting for sampling bias, Africa is clearly a region with the greatest share of emerging VBZD. We highlight critical gaps in our understanding of VBZD emergence and emphasize the importance of interdisciplinary research and consideration of deeper evolutionary processes to improve our capacity for anticipating where and how such diseases have and will continue to emerge.

Vector-borne diseases (VBDs) such as malaria, dengue, and leishmaniasis exert a huge burden of morbidity and mortality worldwide, particularly affecting the poorest of the poor. The principal method by which these diseases are controlled is through vector control, which has a long and distinguished history. Vector control, to a greater extent than drugs or vaccines, has been responsible for shrinking the map of many VBDs. Here, we describe the history of vector control programmes worldwide from the late 1800s to date. Pre 1940, vector control relied on a thorough understanding of vector ecology and epidemiology, and implementation of environmental management tailored to the ecology and behaviour of local vector species. This complex understanding was replaced by a simplified dependency on a handful of insecticide-based tools, particularly for malaria control, without an adequate understanding of entomology and epidemiology and without proper monitoring and evaluation. With the rising threat from insecticide-resistant vectors, global environmental change, and the need to incorporate more vector control interventions to eliminate these diseases, we advocate for continued investment in evidence-based vector control. There is a need to return to vector control approaches based on a thorough knowledge of the determinants of pathogen transmission, which utilise a range of insecticide and non-insecticide-based approaches in a locally tailored manner for more effective and sustainable vector control.

Dengue is an emerging illness in India, where it is endemic in some areas and sometimes causes yearly epidemics. Each dengue outbreak starts with high death and morbidity, which has a significant socioeconomic impact. As of September 30, 2022, India had 63,280 dengue cases, according to information provided by the National Centre for Vector Borne Diseases Control. North India is most severely impacted by each outbreak. In Uttar Pradesh, the state with the most population in India, there have been 2060 confirmed cases of dengue and 1 mortality till September 2022 reported. Patients are being reported from semi-urban, rural, and urban areas. It is essential to properly monitor disease cases through disease surveillance in order to ensure prompt case management if dengue outbreak control is to be achieved. An efficient diagnostic approach for early diagnosis is urgently required to reduce the severity of the sickness, the length of the hospital stay, and clinical consequences.

Vector-borne pathogens commonly known as "haemoparasites" are hemotropic organisms that range from nematodes, protozoa, viruses, and bacteria. This is a retrospective study of the databases of 3,300 dogs that aims to evaluate the frequency by qPCR for 9 hemotropics in the city of Medellín between June 2021 and March 2022, and the correlation of the presence of these agents with the Clinical manifestations and hemoleukograms of 20 positive dogs. Of the total dogs tested, 60% were positive to one or more agents. The number of animals infected with one, two, or three agents was 42.9% (1416/3,300), 17.7% (583/3,300), and 1.3% (42/3,300), respectively. In order from highest to lowest presence of haemoparasites, the number of dogs positive for a single agent was: Anaplasma spp. (14.1%), Mycoplasma spp. (13.9%), Ehrlichia spp. (6.1%), Hepatozoon spp. (5.4%), Babesia spp. (1%), filariae (0.9%), and Bartonella spp. (0.6%). The main clinicopathological alterations in 9 of 20 dogs positive for some haemoparasite and with nonspecific clinical signs (fever, anorexia, myalgia, lethargy) were anemia and/or thrombocytopenia, with or without an inflammatory leukogram. However, the absence of clinicopathological alterations in 11/20 positive animals does not rule out the presence of infection since the animals had a normal blood count. Experimental and field studies have shown that many dogs positive by serology and/or qPCR are clinically normal, and although they do not present an active infection, they may be asymptomatic carriers of haemoparasites. In this study the results are discussed and compared with others carried out in Colombia for the main haemoparasites of dogs. [ABSTRACT FROM AUTHOR]

Aedes aegypti and Aedes albopictus are the vectors of important arboviruses: dengue fever, chikungunya, Zika, and yellow fever. Female mosquitoes acquire arboviruses by feeding on the infected host blood, thus being able to transmit it to their offspring. The intrinsic ability of a vector to infect itself and transmit a pathogen is known as vector competence. Several factors influence the susceptibility of these females to be infected by these arboviruses, such as the activation of the innate immune system through the Toll, immunodeficiency (Imd), JAK-STAT pathways, and the interference of specific antiviral response pathways of RNAi. It is also believed that the presence of non-pathogenic microorganisms in the microbiota of these arthropods could influence this immune response, as it provides a baseline activation of the innate immune system, which may generate resistance against arboviruses. In addition, this microbiome has direct action against arboviruses, mainly due to the ability of Wolbachia spp. to block viral genome replication, added to the competition for resources within the mosquito organism. Despite major advances in the area, studies are still needed to evaluate the microbiota profiles of Aedes spp. and their vector competence, as well as further exploration of the individual roles of microbiome components in activating the innate immune system. [ABSTRACT FROM AUTHOR]

Malaria is the most significant protozoan disease in Africa and the principal vector-borne disease (VBD) in Nigeria, which is influenced by the quality of breeding habitats that are reflected through the stage preceding adult. Control of Anopheles gambiae s.l. populations through source reduction is still considered the most effective way of prevention and control, although it has proven unsustainable in Niger State. Physico-chemical cues were investigated. Samples were taken inside and outside 1 m2 cages weekly by dipping and emptying the cages from May 2019 to March 2020. The data subjected to analysis of variance (one and two-way Anova). The findings revealed the mean pupae abundance (MPA), were significantly higher in Large Water bodies (624.50±217.81), and followed by Gutters (436.00±184.2) and Swamps (285.50±125.06). The mean pupae productivity (MPP), followed the order of descending rate>GT (717.50±219.38)>LW (677.21±145.10)>SW (530.40±136.97). The result also showed that emptying technique (ET) was more sufficient and reliable than dipping technique (DT). The peak abundance and productivity of the pupal stage was June to August then declined in March, 2020 both habitats. However, MPP differed significantly (p<0.05) from one another across the months in all the habitat types. The physical and chemical cues of the breeding sites, varied significantly, except in temperature, total hardness, biochemical oxygen demands, conductivity, and pH in all the habitats. This study revealed high utilization of physico-chemical properties and poses increased risk of malaria. Thus, emphasis on the vector management strategies should be given specially on gutters and large water bodies as breeding habitats of malaria vectors (MV), in Niger State. [ABSTRACT FROM AUTHOR]