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Simple Summary: Dirofilariosis, a zoonotic mosquito-borne disease, remains an under-studied condition in several areas of Brazil, despite its long-standing presence. This review aims to draw together prevalence data from epidemiological studies and case reports conducted in dogs over the last decade and in cats, wildlife, and humans over the last twenty years to define the distribution and prevalence of Dirofilaria spp. within the country and highlight the challenges associated with its diagnosis, treatment, and control. While Dirofilaria immitis is the main species circulating in Brazil, concerns have been raised in recent years about the presence of genetically distinct strains that may be more virulent than their Old World counterparts. In light of this and the widespread distribution of the parasite among both Brazilian coastal and non-coastal areas, further studies are required to characterise the disease. Additionally, there is a need to increase awareness of this neglected disease among health professionals in Brazil and to understand and minimise its impact on both veterinary and public health. Brazil's extensive coastline, tropical and subtropical climate, and well-preserved environment represent a conducive setting for dirofilariosis, a zoonotic mosquito-borne disease. Although this condition has long been recognised in the country, it has been relatively under-studied, and it is currently considered to be an emerging disease. Diagnosis, treatment, and control remain challenging due to the extensive gaps in knowledge. In order to help address this issue, this review aims to (i) summarise the available literature on the distribution of Dirofilaria spp. in Brazilian dogs over the last decade, (ii) review case reports of dirofilariosis in cats, wild animals, and humans over the last twenty years, and (iii) highlight the benefits of taking a One Health approach to managing this disease. While there have been several prevalence studies in dogs, disease distribution is poorly characterised in cats, and little is known about the occurrence of the parasite in wildlife. Human cases are sporadically reported, and no large-scale studies have been undertaken to date. Evidence indicates that Dirofilaria immitis is the main species circulating in Brazil, although Dirofilaria repens has also been detected. Molecular studies have also suggested the circulation of a highly virulent form of D. immitis, which may be genetically distinct from those of the Old World. A programme of epidemiological, ecological, genomic, and pathogenicity-based studies is required to quantify the impact of dirofilariosis in Brazil on both veterinary and public health and to inform others on its control. [ABSTRACT FROM AUTHOR]

In this study, we introduce an enhanced stochastic model for mosquito-borne diseases that incorporates quarantine measures and employs Lévy jumps with the generalized tempered stable (GTS) distribution. Our proposed model lacks both endemic and disease-free states, rendering the conventional approach of assessing disease persistence or extinction based on asymptotic behavior inapplicable. Instead, we adopt a novel stochastic analysis approach to demonstrate the potential for disease eradication or continuation. Numerical examples validate the accuracy of our results and compare the outcomes of our model with the GTS distribution against the standard system using basic Lévy jumps. By accounting for the heavy-tailed nature of disease incidence or vector abundance, the GTS distribution enhances the precision of epidemiological models and predictions. [ABSTRACT FROM AUTHOR]

Due to their vectorial capacity, mosquitoes (Diptera: Culicidae) receive special attention from health authorities and entomologists. These cosmopolitan insects are responsible for the transmission of many viral diseases, such as dengue and yellow fever, causing huge impacts on human health and justifying the intensification of research focused on mosquito-borne diseases. In this context, the study of the virome of mosquitoes can contribute to anticipate the emergence and/or the reemergence of infectious diseases. The assessment of mosquito viromes also contributes to the surveillance of a wide variety of viruses found in these insects, allowing the early detection of pathogens with public health importance. However, the study of mosquito viromes can be challenging due to the number and complexities of steps involved in this type of research. Therefore, this article aims to describe, in a straightforward and simplified way, the steps necessary for obtention and assessment of mosquito viromes. In brief, this article explores: the capture and preservation of specimens; sampling strategies; treatment of samples before DNA/RNA extraction; extraction methodologies; enrichment and purification processes; sequencing choices; and bioinformatics analysis. [ABSTRACT FROM AUTHOR]

Background: West Nile virus (WNV) is an emerging mosquito-borne neurotropic virus, belonging to the Flaviviridae family and the Orthoflavivirus genus. The effective control of WNV requires a targeted preventive strategy that also needs the identification of the higher-risk populations. Hence, this study focused on a systematic literature review of WNV-acquired infection in work-related settings and the assessment of the exposure risks among different occupational categories. Methods: A comprehensive search was conducted to identify studies until September 2023 in multiple databases such as PubMed/MEDLINE, SCOPUS and Web of Science, according to the PRISMA 2020 statement. Risk of bias of collected papers was assessed by the ROB tool of the National Toxicology Program's Office of Health Assessment and Translation handbook. Results: A total of 21 studies were included in the systematic review, out of which seventeen were observational studies and four were case reports. Workers identified as at higher risk for WNV infection were military workers, veterinarians, agricultural workers, farmers, and laboratory workers with contact with infected fluids or aerosols. Conclusions: The identification of higher-risk workers could facilitate active surveillance by occupational physicians, which could improve our understanding of the epidemiology of WNV and, in addition, could help tailor appropriate preventive recommendations, reducing the overall burden of disease in high-risk areas. [ABSTRACT FROM AUTHOR]

Arboviral infections transmitted by Aedes spp. mosquitoes are a major threat to human health, particularly in tropical regions but are expanding to temperate regions. The ability of Aedes aegypti and Aedes albopictus to transmit multiple arboviruses involves a complex relationship between mosquitoes and the virus, with recent discoveries shedding light on it. Furthermore, this relationship is not solely between mosquitoes and arboviruses, but also involves the mosquito microbiome. Here, we aimed to construct a comprehensive review of the latest information about the arbovirus infection process in A. aegypti and A. albopictus, the source of mosquito microbiota, and its interaction with the arbovirus infection process, in terms of its implications for vectorial competence. First, we summarized studies showing a new mechanism for arbovirus infection at the cellular level, recently described innate immunological pathways, and the mechanism of adaptive response in mosquitoes. Second, we addressed the general sources of the Aedes mosquito microbiota (bacteria, fungi, and viruses) during their life cycle, and the geographical reports of the most common microbiota in adults mosquitoes. How the microbiota interacts directly or indirectly with arbovirus transmission, thereby modifying vectorial competence. We highlight the complexity of this tripartite relationship, influenced by intrinsic and extrinsic conditions at different geographical scales, with many gaps to fill and promising directions for developing strategies to control arbovirus transmission and to gain a better understanding of vectorial competence. The interactions between mosquitoes, arboviruses and their associated microbiota are yet to be investigated in depth. [ABSTRACT FROM AUTHOR]

In this article, we have proposed an non-autonomous mathematical model to describe the dynamics of mosquito-borne diseases taking into account seasonal variation. In the proposed model, the disease transmission rate and the growth rate of aquatic mosquito populations are considered seasonally. The non-autonomous model is shown to have a disease-free, globally asymptotically stable cyclic state whenever the time-dependent reproduction number RC(t) is less than unity. From the model analysis, we find that a unique positive endemic periodic solution of a non-autonomous system exists only when RC(t) > 1. The persistence and severity of an epidemic can be described by a time-dependent periodic reproduction number RC(t). Furthermore, it is shown that if RC(t) <1, the disease will not spread and may eventually disappear. We also propose an optimal control problem applied to control the disease with two other parameters namely insecticide and spraying. It has been shown that a control strategy consisting of insecticides and combined spraying can have a synergistic effect in reducing the incidence of mosquito-borne diseases. Finally, numerical simulations are performed to illustrate the results of our analysis. [ABSTRACT FROM AUTHOR]

Background: Mosquitoes are the deadliest organisms in the world, killing an estimated 750,000 people per year due to the pathogens they can transmit. Mosquitoes also pose a major threat to other vertebrate animals. Culex territans is a mosquito species found in temperate zones worldwide that feeds almost exclusively on amphibians and can transmit parasites; however, little is known about its ability to transmit other pathogens, including fungi. Batrachochytrium dendrobatidis (Bd) is a topical pathogenic fungus that spreads through contact. With amphibian populations around the world experiencing mass die-offs and extinctions due to this pathogen, it is critical to study all potential modes of transmission. Because Cx. territans mosquitoes are in contact with their hosts for long periods of time while blood-feeding, we hypothesize that they can transmit and pick up Bd. Methods: In this study, we first assessed Cx. territans ability to transfer the fungus from an infected surface to a clean one under laboratory conditions. We also conducted a surveillance study of Bd infections in frogs and mosquitoes in the field (Mountain Lake Biological station, VA, USA). In parallel, we determined Cx. territans host preference via blood meal analysis of field caught mosquitoes. Results: We found that this mosquito species can carry the fungus to an uninfected surface, implying that they may have the ability to transmit Bd to their amphibian hosts. We also found that Cx. territans feed primarily on green frogs (Rana clamitans) and bullfrogs (Rana catesbeiana) and that the prevalence of Bd within the frog population at our field site varied between years. Conclusions: This study provides critical insights into understanding the role of amphibian-biting mosquitoes in transmitting pathogens, which can be applied to disease ecology of susceptible amphibian populations worldwide. [ABSTRACT FROM AUTHOR]

Mosquitoes (Diptera: Culicidae) are considered to be huge threat among millions of peoples, animals, and other living organisms in the world. Most of the vector borne diseases such as malaria, filariasis, dengue hemorrhagic fever, chikungunya, Japanese encephalitis etc., created huge impact on humans in all over the world. Vector diseases in Kingdom of Saudi Arabia are increasing day by day and their control measures taken through the government sectors for eradicating the vectors helps in controlling the diseases but still more approaches to be implemented or assimilated. Most of the synthetic or chemical based insecticides to control mosquitoes developed resistance among their communities even though they showed their potential in controlling the vector in initial days. Botanical insecticides from plant‐based origin such as active compounds, essential oils, green synthesized nanomaterials, and microbial secondary metabolites helps more efficiency in controlling vectors. Mode of action against vectors differs based on its persisting active ingredients, such as larvicidal, pupicidal, adulticidal, oviposition, morphological changes etc. Even though number of research works has been carried out against mosquito species, there is only limited number of studies undergone against mosquito vectors from Saudi Arabia origin. Hence this review will give us the current knowledge on the effectiveness of botanical insecticides against major mosquito vectors from Saudi Arabia. Thus, it gives more significant against medical and veterinary sectors. [ABSTRACT FROM AUTHOR]

Simple Summary: Mosquitoes are able to transmit a wide variety of devastating pathogens when they bite and obtain blood from their vertebrate hosts. Therefore, identifying the physiological processes required for biting by vector mosquitoes can contribute to developing strategies to suppress biting behavior and prevent disease transmission. In this study, we investigate the differential expression of small regulatory RNAs (microRNAs) between different strains of the Northern house mosquito, Culex pipiens, which is a major vector of West Nile virus and filarial nematodes. We measured differential microRNA expression specifically in the context of a behavioral biting assay, using populations with previously documented differences in biting propensity and the ability to produce eggs without a blood meal. We identified eight differentially expressed microRNAs; six of these are implicated in regulating physiological processes related to energy utilization, reproduction, and immunity. Our results are strikingly similar to previous studies demonstrating increased expression of messenger RNA-encoding proteins involved in energy utilization in association with biting. Furthermore, while previous studies have identified changes in microRNA expression occurring after consuming a blood meal, ours is the first study to demonstrate anticipatory changes in microRNA expression before blood is consumed. Understanding the molecular and physiological processes underlying biting behavior in vector mosquitoes has important implications for developing novel strategies to suppress disease transmission. Here, we conduct small-RNA sequencing and qRT-PCR to identify differentially expressed microRNAs (miRNAs) in the head tissues of two subspecies of Culex pipiens that differ in biting behavior and the ability to produce eggs without blood feeding. We identified eight differentially expressed miRNAs between biting C. pipiens pipiens (Pipiens) and non-biting C. pipiens molestus (Molestus); six of these miRNAs have validated functions or predicted targets related to energy utilization (miR8-5-p, miR-283, miR-2952-3p, miR-1891), reproduction (miR-1891), and immunity (miR-2934-3p, miR-92a, miR8-5-p). Although miRNAs regulating physiological processes associated with blood feeding have previously been shown to be differentially expressed in response to a blood meal, our results are the first to demonstrate differential miRNA expression in anticipation of a blood meal before blood is actually imbibed. We compare our current miRNA results to three previous studies of differential messenger RNA expression in the head tissues of mosquitoes. Taken together, the combined results consistently show that biting mosquitoes commit to specific physiological processes in anticipation of a blood meal, while non-biting mosquitoes mitigate these anticipatory costs. [ABSTRACT FROM AUTHOR]

As the global temperature rises in the coming decades, Aedes albopictus is expected to invade and establish in South East England, where Culex pipiens is currently the most common native mosquito species. Biocontrol measures that use local cyclopoid copepods against Ae. albopictus may be compromised if the copepods prefer alternate Cx. pipiens prey. In this study, I assessed the predation efficiency of Megacyclops viridis copepods against Ae. albopictus larvae from France and larvae that hatched from egg rafts of Cx. pipiens collected in South East England. The experiments were conducted at 15 and 25°C, which are representative of present and future summer temperatures in South East England. Ae. albopictus larvae that survived the course of the experiment in the predator‐absent controls were significantly smaller than Cx. pipiens larvae that survived in the absence of predation. The background mortality of Cx. pipiens larvae increased with the 10‐degree increase in temperature, and the smaller size of surviving Cx. pipiens larvae at 25°C, relative to survivors at 15°C, suggests that larger Cx. pipiens larvae were more likely to die at the higher temperature setting. Across all experimental treatments, the ratio of copepod body length to mean prey length, based on larval lengths of survivors from the corresponding predator‐absent controls, was a significant predictor of the copepod's predation efficiency. Adding temperature setting to the predation efficiency model as a predictor did not improve model fit. Within the mixed prey treatments, the predation efficiency of M. viridis was 34.5 percentage points higher against Ae. albopictus prey than against Cx. pipiens prey. The higher predation efficiency that M. viridis exhibited against invasive Ae. albopictus prey, likely due to the smaller size of these larvae, supports the future use of M. viridis as a biocontrol agent in the United Kingdom. [ABSTRACT FROM AUTHOR]

Since 2010, the West Nile virus (WNV) has been established in Greece. We describe the epidemiology of diagnosed human WNV infections in Greece with a focus on the 2022 season. During the transmission period, clinicians were sending samples from suspected cases for testing. Active laboratory-based surveillance was performed with immediate notification of diagnosed cases. We collected clinical information and interviewed patients on a timely basis to identify their place of exposure. Besides serological and molecular diagnostic methods, next-generation sequencing was also performed. In 2022, 286 cases of WNV infection were diagnosed, including 278 symptomatic cases and 184 (64%) cases with neuroinvasive disease (WNND); 33 patients died. This was the third most intense season concerning the number of WNND cases, following 2018 and 2010. Most (96%) cases were recorded in two regions, in northern and central Greece. The virus strain was a variant of previous years, clustering into the Central European subclade of WNV lineage 2. The 2022 WNV season was quite intense in Greece. The prompt diagnosis and investigation of cases are considered pivotal for the timely response, while the availability of whole genome sequences enables studies on the molecular epidemiology of the disease. [ABSTRACT FROM AUTHOR]

It is natural that mosquitoes move towards high human population density and environmental heterogeneity plays a pivotal role in disease transmission, and thus we formulate and analyse a mosquito-borne disease model with chemotaxis and spatial heterogeneity. The global existence and boundedness of solutions are proven to guarantee the solvability of the model and is challenging due to the model complexity. Under appropriate conditions, we demonstrate that the disease-free equilibrium is globally asymptotically stable provided that the basic reproduction number |$\mathcal{R}_0$| is less than one, and the system is uniformly persistent and admits at least one endemic equilibrium if |$\mathcal{R}_0$| is greater than one. Furthermore, we numerically explore the impacts of chemotactic effect, spatial heterogeneity and dispersal rates of infected individuals to provide a clear picture on disease severity. In particular, the mosquito chemotaxis causes mild disease in some regions but severe in others, which suggests developing targeted strategies to control mosquitoes in specific locations and achieve a deep understanding on the chemotaxis. [ABSTRACT FROM AUTHOR]

Chikungunya, a mosquito‐borne disease, is posing threat to neonatal population in Cambodia because of its challenging diagnosis and insufficient attention compared with Dengue. In what follows, we present a case of serologically‐confirmed congenital chikungunya in a newborn presenting early‐onset sepsis, and the mother was underdiagnosed with intrapartum flu‐like infection. [ABSTRACT FROM AUTHOR]

Ross River virus (RRV) is the most common mosquito-borne infection in Australia. RRV disease is characterised by joint pain and lethargy, placing a substantial burden on individual patients, the healthcare system and economy. This burden is compounded by a lack of effective treatment or vaccine for the disease. The complex RRV disease ecology cycle includes a number of reservoirs and vectors that inhabit a range of environments and climates across Australia. Climate is known to influence humans, animals and the environment and has previously been shown to be useful to RRV prediction models. We developed a negative binomial regression model to predict monthly RRV case numbers and outbreaks in the Darling Downs region of Queensland, Australia. Human RRV notifications and climate data for the period July 2001 – June 2014 were used for model training. Model predictions were tested using data for July 2014 – June 2019. The final model was moderately effective at predicting RRV case numbers (Pearson's r = 0.427) and RRV outbreaks (accuracy = 65%, sensitivity = 59%, specificity = 73%). Our findings show that readily available climate data can provide timely prediction of RRV outbreaks. [ABSTRACT FROM AUTHOR]

Usutu virus (USUV) is an emerging zoonotic arbovirus in Europe, where it primarily impacts Eurasian blackbirds (Turdus merula). For mosquito‐borne viruses to persist in temperate areas, transovarial transmission in vectors or overwintering in either hosts or diapausing vectors must occur to facilitate autochthonous transmission. We undertook surveillance of hosts and vectors in 2021 to elucidate whether USUV had overwintered in the United Kingdom (UK) following its initial detection there in 2020. From 175 dead bird submissions, we detected 1 case of USUV infection, in a blackbird, from which a full USUV genome was derived. Using a molecular clock analysis, we demonstrate that the 2021 detection shared a most recent common ancestor with the 2020 Greater London, UK, USUV sequence. In addition, we identified USUV‐specific neutralizing antibodies in 10 out of 86 serum samples taken from captive birds at the index site, demonstrating in situ cryptic infection and potential sustained transmission. However, from 4966 mosquitoes, we detected no USUV RNA suggesting that prevalence in the vector community was absent or low during sampling. Combined, these results suggest that USUV overwintered in the UK, thus providing empirical evidence for the continued northward expansion of this vector‐borne viral disease. Currently, our detection indicates geographically restricted virus persistence. Further detections over time will be required to demonstrate long‐term establishment. It remains unclear whether the UK, and by extension other high‐latitude regions, can support endemic USUV infection. [ABSTRACT FROM AUTHOR]

Simple Summary: Mosquitoes are the most important group of flies affecting human health and wellness. Worldwide, mosquito-borne diseases kill over 700,000 people every year and afflict millions more. Mosquitoes also adversely affect domestic and agricultural animal health and negatively impact tourism-based economies. The Florida Keys Mosquito Control District is responsible for reducing mosquito populations in an area stretching from Cross Key and Broad Creek in the northeast to Key West in the southwest. Before mosquitoes can be controlled, it is important to know how many mosquitoes there are, what species are present, and where they are located. Adult mosquito surveillance traps such as the BG Sentinel, set around homes and businesses, and light traps, set in field sites, are used to identify the number and species of mosquitoes in an area. Larval and pupal mosquito surveillance is conducted by visiting water sources in domestic and field habitats to look for immature mosquitoes. Surveillance informs operational staff of the types of treatments required to control mosquitoes present. Products currently used to kill larval and adult forms of mosquitoes are continuously evaluated for efficacy to reduce pesticide-resistant populations. Mosquito control programs in the State of Florida are charged with protecting human and animal health, fostering economic development of the State, permitting enjoyment of the natural attractions in Florida, and improving the quality of life of citizens. Mosquito control programs must accomplish these tasks in such a manner as will protect the environment and terrestrial, marine, and freshwater ecosystems. The Florida Keys Mosquito Control District provides a science-based Integrated Pest Management mosquito control program to the residents of the Florida Keys, Monroe County, Florida. Operational decisions are based on surveillance of adult and immature mosquitoes. Mosquito populations are monitored by means of carbon dioxide-baited light traps BG Sentinel traps, truck traps, gravid traps, oviposition traps, and human landing rate counts. Larvae and pupae are monitored by inspections of natural and human-made immature habitats. Due to past and current reliance on chemical pesticides for control of mosquitoes, the District maintains a pesticide resistance detection program consisting of CDC bottle bioassays and larval bioassays, challenging local mosquito species with currently used adulticides and larvicides. [ABSTRACT FROM AUTHOR]

Most of the vector-borne diseases show a clear dependence on seasonal variation, including climate change. In this paper, we proposed a nonautonomous mathematical model consisting of a periodic system of nonlinear differential equations. In the proposed model, the realistic functional forms for the different temperature-dependent parameters are considered. The autonomous system of the proposed model is also analyzed. The nontrivial solution of the autonomous model is locally asymptotically stable if R 0 < 1. It is shown that a unique endemic equilibrium point of the autonomous model exists when R 0 > 1 and proved that endemic solution is linearly stable when R 0 > 1. The nonautonomous model is shown to have a nontrivial disease-free periodic state, which is globally asymptotically stable whenever temperature-dependent reproduction number is less than unity. It is observed that a unique positive endemic periodic solution of the nonautonomous system exists only when a temperature-dependent reproduction number greater than unity, which makes for the persistence of the disease. Numerical simulation has been carried out to support the analytical results and shows the effects of temperature variability in the life span of mosquitoes as well as the persistence of the disease. [ABSTRACT FROM AUTHOR]

However, in addition to visual traits (e.g. coloration, size, etc.), people also distinguished between mosquito species based on their activity times, noting the difference between diurnal and crepuscular mosquitoes and how this influenced their interactions with mosquitoes. Experiences of mosquito diversity tended to focus on distinguishing I Aedes i mosquitoes from other mosquito genera within a site. One community member described the timing of her interactions with mosquitoes, demonstrating in-depth knowledge of mosquito behaviours: The white-striped ones [referencing Aedes mosquitoes] would be biting us around now [late afternoon]. However, mosquito-borne disease transmission occurs at the intersection of mosquito vectors and human hosts, and so we must also examine patterns in individuals' experiences with mosquitoes, questioning where, how and why they may encounter high mosquito burdens. Keywords: mixed methods; mosquito-borne disease; urbanization EN mixed methods mosquito-borne disease urbanization 730 743 14 06/10/22 20220601 NES 220601 INTRODUCTION Urban environments are heterogeneous landscapes of social and environmental features, with important consequences for human-nature interactions. [Extracted from the article]

Mosquitoes transmit a wide variety of devastating pathogens when they bite vertebrate hosts and feed on their blood. However, three entire mosquito genera and many individual species in other genera have evolved a nonbiting life history in which blood is not required to produce eggs. Our long‐term goal is to develop novel interventions that reduce or eliminate the biting behavior in vector mosquitoes. A previous study used biting and nonbiting populations of a nonvector mosquito, Wyeomyia smithii, as a model to uncover the transcriptional basis of the evolutionary transition from a biting to a nonbiting life history. Herein, we ask whether the molecular pathways that were differentially expressed due to differences in biting behavior in W. smithii are also differentially expressed between subspecies of Culex pipiens that are obligate biting (Culex pipiens pipiens) and facultatively nonbiting (Culex pipiens molestus). Results from RNAseq of adult heads show dramatic upregulation of transcripts in the ribosomal protein pathway in biting C. pipiens, recapitulating the results in W. smithii, and implicating the ancient and highly conserved ribosome as the intersection to understanding the evolutionary and physiological basis of blood feeding in mosquitoes. Biting Culex also strongly upregulate energy production pathways, including oxidative phosphorylation and the citric acid (TCA) cycle relative to nonbiters, a distinction that was not observed in W. smithii. Amino acid metabolism pathways were enriched for differentially expressed genes in biting versus nonbiting Culex. Relative to biters, nonbiting Culex upregulated sugar metabolism and transcripts contributing to reproductive allocation (vitellogenin and cathepsins). These results provide a foundation for developing strategies to determine the natural evolutionary transition between a biting and nonbiting life history in vector mosquitoes. [ABSTRACT FROM AUTHOR]

In this paper, we obtain the complete information about the existence and nonexistence of traveling wave solution (TWS) for a reaction–diffusion model of mosquito-borne disease with general incidence and constant recruitment. We find that the basic reproduction ratio R 0 of the corresponding kinetic system and the minimal wave speed c ∗ are thresholds to determine the existence of TWS. With the aid of limiting arguments and Lyapunov approach, it is demonstrated that the system possesses a nontrivial TWS with wave speed c ≥ c ∗ connecting the disease-free equilibrium and endemic equilibrium when R 0 > 1 . When R 0 ≤ 1 and c > 0 , the nonexistence of nontrivial TWS is obtained by contradiction. By means of a rather ingenious method that is easier to understand than Laplace transform, we show that there is no nontrivial TWS when R 0 > 1 and 0 < c < c ∗ . Numerically, we perform simulations to verify the analytical results and explore the sensitivity of the speed c ∗ on parameters. The sensitivity results show that the parameters related to mosquitoes have a greater impact on c ∗ . [ABSTRACT FROM AUTHOR]

Background: Aerial applications of insecticides that target adult mosquitoes are widely used to reduce transmission of West Nile virus to humans during periods of epidemic risk. However, estimates of the reduction in abundance following these treatments typically focus on single events, rely on pre-defined, untreated control sites and can vary widely due to stochastic variation in population dynamics and trapping success unrelated to the treatment. Methods: To overcome these limitations, we developed generalized additive models fitted to mosquito surveillance data collected from CO2-baited traps in Sacramento and Yolo counties, California from 2006 to 2017. The models accounted for the expected spatial and temporal trends in the abundance of adult female Culex (Cx.) tarsalis and Cx. pipiens in the absence of aerial spraying. Estimates for the magnitude of deviation from baseline abundance following aerial spray events were obtained from the models. Results: At 1-week post-treatment with full spatial coverage of the trapping area by pyrethroid or pyrethrin products, Cx. pipiens abundance was reduced by a mean of 52.4% (95% confidence intrval [CI] − 65.6, − 36.5%) while the use of at least one organophosphate pesticide resulted in a mean reduction of 76.2% (95% CI − 82.8, − 67.9%). For Cx. tarsalis, at 1-week post-treatment with full coverage there was a reduction in abundance of 30.7% (95% CI − 54.5, 2.5%). Pesticide class was not a significant factor contributing to the reduction. In comparison, repetition of spraying over three to four consecutive weeks resulted in similar estimates for Cx. pipiens and estimates of somewhat smaller magnitude for Cx. tarsalis. Conclusions: Aerial adulticides are effective for achieving a rapid short-term reduction of the abundance of the primary West Nile virus vectors, Cx. tarsalis and Cx. pipiens. A larger magnitude of reduction was estimated in Cx. pipiens, possibly due to the species' focal distribution. Effects of aerial sprays on Cx. tarsalis populations are likely modulated by the species' large dispersal ability, population sizes and vast productive larval habitat present in the study area. Our modeling approach provides a new way to estimate effects of public health pesticides on vector populations using routinely collected observational data and accounting for spatio-temporal trends and contextual factors like weather and habitat. This approach does not require pre-selected control sites and expands upon past studies that have focused on the effects of individual aerial treatment events. [ABSTRACT FROM AUTHOR]

Background: Estimates of the geographical distribution of Culex mosquitoes in the Americas have been limited to state and provincial levels in the United States and Canada and based on data from the 1980s. Since these estimates were made, there have been many more documented observations of mosquitoes and new methods have been developed for species distribution modeling. Moreover, mosquito distributions are affected by environmental conditions, which have changed since the 1980s. This calls for updated estimates of these distributions to understand the risk of emerging and re-emerging mosquito-borne diseases. Methods: We used contemporary mosquito data, environmental drivers, and a machine learning ecological niche model to create updated estimates of the geographical range of seven predominant Culex species across North America and South America: Culex erraticus, Culex nigripalpus, Culex pipiens, Culex quinquefasciatus, Culex restuans, Culex salinarius, and Culex tarsalis. Results: We found that Culex mosquito species differ in their geographical range. Each Culex species is sensitive to both natural and human-influenced environmental factors, especially climate and land cover type. Some prefer urban environments instead of rural ones, and some are limited to tropical or humid areas. Many are found throughout the Central Plains of the USA. Conclusions: Our updated contemporary Culex distribution maps may be used to assess mosquito-borne disease risk. It is critical to understand the current geographical distributions of these important disease vectors and the key environmental predictors structuring their distributions not only to assess current risk, but also to understand how they will respond to climate change. Since the environmental predictors structuring the geographical distribution of mosquito species varied, we hypothesize that each species may have a different response to climate change. [ABSTRACT FROM AUTHOR]

Background: Estimates of the geographical distribution of Culex mosquitoes in the Americas have been limited to state and provincial levels in the United States and Canada and based on data from the 1980s. Since these estimates were made, there have been many more documented observations of mosquitoes and new methods have been developed for species distribution modeling. Moreover, mosquito distributions are affected by environmental conditions, which have changed since the 1980s. This calls for updated estimates of these distributions to understand the risk of emerging and re-emerging mosquito-borne diseases. Methods: We used contemporary mosquito data, environmental drivers, and a machine learning ecological niche model to create updated estimates of the geographical range of seven predominant Culex species across North America and South America: Culex erraticus, Culex nigripalpus, Culex pipiens, Culex quinquefasciatus, Culex restuans, Culex salinarius, and Culex tarsalis. Results: We found that Culex mosquito species differ in their geographical range. Each Culex species is sensitive to both natural and human-influenced environmental factors, especially climate and land cover type. Some prefer urban environments instead of rural ones, and some are limited to tropical or humid areas. Many are found throughout the Central Plains of the USA. Conclusions: Our updated contemporary Culex distribution maps may be used to assess mosquito-borne disease risk. It is critical to understand the current geographical distributions of these important disease vectors and the key environmental predictors structuring their distributions not only to assess current risk, but also to understand how they will respond to climate change. Since the environmental predictors structuring the geographical distribution of mosquito species varied, we hypothesize that each species may have a different response to climate change. [ABSTRACT FROM AUTHOR]

Loss of biodiversity can affect transmission of infectious diseases in at least two ways: by altering host and vector abundance or by influencing host and vector behaviour. We used a large herbivore exclusion experiment to investigate the effects of wildlife loss on the abundance and feeding behaviour of mosquito vectors and to explore consequences for vector‐borne disease transmission. Large herbivore loss affected both mosquito abundance and blood‐feeding behaviour. For Aedes mcintoshi, the dominant mosquito species in our study and a primary vector of Rift Valley fever virus (RVFV), abundance decreased with large herbivore loss, while blood feeding on humans increased. Despite an elevated human biting rate in the absence of large herbivores, we estimated that the potential for RVFV transmission to humans doubles in the presence of large herbivores. These results demonstrate that multiple effects of biodiversity loss on vectors can lead to counterintuitive outcomes for human disease risk. [ABSTRACT FROM AUTHOR]

Background: Eastern equine encephalitis virus (EEEV) is a mosquito-borne virus that is primarily found in North America and the Caribbean. Over the past decade there has been an increase in virus activity, including large outbreaks in human and horse populations. Predicted climate change is expected to affect the range of mosquitoes including vectors of EEEV, which may alter disease risk posing a public health concern. Methods: A scoping review (ScR) was conducted to identify and characterize the global evidence on EEEV. A thorough search was conducted in relevant bibliographic databases and government websites. Two reviewers screened titles and abstracts for relevance and the characteristics of relevant articles were extracted using a uniformly implemented data collection form. The study protocol was developed a priori and described the methods and tools used and this article follows the PRISMA-ScR guidelines for reporting ScRs. Results: The ScR included 718 relevant research articles. The majority of the articles originated from North America (97%) between 1933 and 2019. EEEV has been identified in 35 species of mosquitoes, over 200 species of birds, various domestic animals, wild mammals, reptiles, and amphibians. Articles identified in this ScR primarily covered three topic areas: epidemiology of hosts and vectors (344 articles) including surveillance results (138), pathogenesis of EEEV in hosts (193), and in vitro studies characterizing EEEV (111). Fewer articles evaluated the accuracy of diagnostic tests (63), the efficacy of mitigation strategies (62), transmission dynamics (56), treatment of EEEV in hosts (10), societal knowledge, attitudes, and perceptions (4), and economic burden (2). Conclusion: With the projected impact of climate change on mosquito populations, it is expected that the risk of EEEV could change resulting in higher disease burden or spread into previously unaffected areas. Future research efforts should focus on closing some of the important knowledge gaps identified in this ScR. [ABSTRACT FROM AUTHOR]

Background: Aerial applications of insecticides that target adult mosquitoes are widely used to reduce transmission of West Nile virus to humans during periods of epidemic risk. However, estimates of the reduction in abundance following these treatments typically focus on single events, rely on pre-defined, untreated control sites and can vary widely due to stochastic variation in population dynamics and trapping success unrelated to the treatment. Methods: To overcome these limitations, we developed generalized additive models fitted to mosquito surveillance data collected from CO2-baited traps in Sacramento and Yolo counties, California from 2006 to 2017. The models accounted for the expected spatial and temporal trends in the abundance of adult female Culex (Cx.) tarsalis and Cx. pipiens in the absence of aerial spraying. Estimates for the magnitude of deviation from baseline abundance following aerial spray events were obtained from the models. Results: At 1-week post-treatment with full spatial coverage of the trapping area by pyrethroid or pyrethrin products, Cx. pipiens abundance was reduced by a mean of 52.4% (95% confidence intrval [CI] − 65.6, − 36.5%) while the use of at least one organophosphate pesticide resulted in a mean reduction of 76.2% (95% CI − 82.8, − 67.9%). For Cx. tarsalis, at 1-week post-treatment with full coverage there was a reduction in abundance of 30.7% (95% CI − 54.5, 2.5%). Pesticide class was not a significant factor contributing to the reduction. In comparison, repetition of spraying over three to four consecutive weeks resulted in similar estimates for Cx. pipiens and estimates of somewhat smaller magnitude for Cx. tarsalis. Conclusions: Aerial adulticides are effective for achieving a rapid short-term reduction of the abundance of the primary West Nile virus vectors, Cx. tarsalis and Cx. pipiens. A larger magnitude of reduction was estimated in Cx. pipiens, possibly due to the species' focal distribution. Effects of aerial sprays on Cx. tarsalis populations are likely modulated by the species' large dispersal ability, population sizes and vast productive larval habitat present in the study area. Our modeling approach provides a new way to estimate effects of public health pesticides on vector populations using routinely collected observational data and accounting for spatio-temporal trends and contextual factors like weather and habitat. This approach does not require pre-selected control sites and expands upon past studies that have focused on the effects of individual aerial treatment events. [ABSTRACT FROM AUTHOR]

Travel frequency of people varies widely with occupation, age, gender, ethnicity, income, climate and other factors. Meanwhile, the distribution of the numbers of times people in different regions or with different travel behaviors bitten by mosquitoes may be nonuniform. To reflect these two heterogeneities, we develop a multipatch model to study the impact of travel frequency and human biting rate on the spatial spread of mosquito-borne diseases. The human population in each patch is divided into four classes: susceptible unfrequent, infectious unfrequent, susceptible frequent, and infectious frequent. The basic reproduction number R0 is defined. It is shown that the disease-free equilibrium is globally asymptotically stable if R0 ≤ 1, and there is a unique endemic equilibrium that is globally asymptotically stable if R0 > 1. A more detailed study is conducted on the single patch model. We use analytical and numerical methods to demonstrate that the model without considering the difference of humans in travel frequency mostly underestimates the risk of infection. Numerical simulations suggest that the greater the difference in travel frequency, the larger the underestimate of the transmission potential. In addition, the basic reproduction number R0 may decreasingly, or increasingly, or nonmonotonically vary when more people travel frequently. [ABSTRACT FROM AUTHOR]

BACKGROUND The fact that bats suppress agricultural pests has been measured for some particular dyads of predator and prey species in both economic and food security terms. The recent emergence of new molecular techniques allows for more precise screenings of bat's diet than the traditional visual identification systems and provides further evidence that bats consume an ample array of agricultural pest species. The main focus of the regulatory services that bats provide in agroecosystems has been on crop pests that cause yield losses. Rice paddies constitute a particular agronomic system with specific challenges, not only related to crop productivity but also to human health. Dipteran density in such ecosystems poses a serious threat to human wellbeing and hinders crop production. Mosquitoes cause direct harm to human populations, transmitting a number of infectious diseases. Non‐biting midges (Chironomidae) can consume and weaken rice seedlings and can cause major yield losses. RESULTS: Mosquito populations and bat activity were assessed in rice paddies of Montgrí, Medes i Baix Ter Natural Park (NE Iberian Peninsula). Molecular analyses of bats faeces (6‐weekly samples of 15 faeces each between mid‐August and September) proved the presence of both mosquitoes and nonbiting midges in all diet samples. Furthermore, bat activity at the sampling locations was related to adult mosquito density. CONCLUSION: Our results suggest that bats actively exploit the emergence of adult mosquitoes and further prove that they prey on mosquitoes, nonbiting midges and other deleterious insects. Promoting the presence of bats next to human settlements in such agroecosystems may constitute a biological control system with direct impact on both human health and crop yield. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background: After Action Reviews (AAR) with a One Health perspective were performed in Slovenia, Italy, Serbia and Greece following a severe West Nile virus (WNV) transmission season in 2018. A protocol combining traditional techniques and organizational process analysis was developed and then implemented in each country. Results: In 2018, response to the unusually intense transmission season of WNV in Slovenia, Italy, Serbia and Greece took place through routine response mechanisms. None of the four countries declared a national or subnational emergency. We found a very strong consensus on the strengths identified in responding to this event. All countries indicated the availability of One Health Plans for surveillance and response; very high laboratory diagnostic capacity in the human, veterinary and entomology sectors and strong inter-sectoral collaboration with strong commitment of engaged institutions as critical in the management of the event. Finally, countries implementing One Health surveillance for WNV (in terms of early warning and early activation of prevention measures) consistently reported a positive impact on their activities, in particular when combining mosquito and bird surveillance with surveillance of cases in humans and equids. Recurring priority areas for improvement included: increasing knowledge on vector-control measures, ensuring the sustainability of vector monitoring and surveillance, and improving capacity to manage media pressure. Conclusions: The AARs presented here demonstrate the benefit of cross-sectoral and cross-disciplinary approaches to preparedness for West Nile virus outbreaks in Europe. In the coming years, priorities include fostering and strengthening arrangements that: enable coordinated One Health surveillance and response during WNV transmission seasons; ensure adequate laboratory capacities; strengthen risk communication; and fund longer-term research to address the knowledge gaps identified in this study. [ABSTRACT FROM AUTHOR]

Background: After Action Reviews (AAR) with a One Health perspective were performed in Slovenia, Italy, Serbia and Greece following a severe West Nile virus (WNV) transmission season in 2018. A protocol combining traditional techniques and organizational process analysis was developed and then implemented in each country.Results: In 2018, response to the unusually intense transmission season of WNV in Slovenia, Italy, Serbia and Greece took place through routine response mechanisms. None of the four countries declared a national or subnational emergency. We found a very strong consensus on the strengths identified in responding to this event. All countries indicated the availability of One Health Plans for surveillance and response; very high laboratory diagnostic capacity in the human, veterinary and entomology sectors and strong inter-sectoral collaboration with strong commitment of engaged institutions as critical in the management of the event. Finally, countries implementing One Health surveillance for WNV (in terms of early warning and early activation of prevention measures) consistently reported a positive impact on their activities, in particular when combining mosquito and bird surveillance with surveillance of cases in humans and equids. Recurring priority areas for improvement included: increasing knowledge on vector-control measures, ensuring the sustainability of vector monitoring and surveillance, and improving capacity to manage media pressure.Conclusions: The AARs presented here demonstrate the benefit of cross-sectoral and cross-disciplinary approaches to preparedness for West Nile virus outbreaks in Europe. In the coming years, priorities include fostering and strengthening arrangements that: enable coordinated One Health surveillance and response during WNV transmission seasons; ensure adequate laboratory capacities; strengthen risk communication; and fund longer-term research to address the knowledge gaps identified in this study. [ABSTRACT FROM AUTHOR]

1. Multiple predator interactions may profoundly alter ecological community dynamics and can complicate predictions of simpler pairwise predator–prey interaction strengths. In particular, multiple predator effects may lessen or enhance prey risk, with implications for community‐level stability. Such emergent effects may modulate natural enemy efficacy towards target organisms. 2. In the present study, a functional response approach was used to quantify emergent multiple predator effects among natural enemies towards the disease vector mosquito complex, Culex pipiens. Conspecific multiple predator–predator interactions of the cyclopoid copepod Macrocyclops albidus (intermediate predator) were quantified by comparing multiple predator consumption simulations, based on individual consumption rates, with multiple predator consumption rates that were experimentally observed. Further, the study examined the influence of the presence of a predator at a higher trophic level, Chaoborus flavicans, on copepod group predation. 3. Both predators displayed type II functional responses, with C. flavicans consuming significantly more prey than M. albidus individually. Overall consumption levels of mosquitoes increased with greater predator density and richness. Antagonistic or synergistic emergent multiple predator effects between conspecifics of M. albidus were not detected, and the higher‐level predator did not reduce effects of the intermediate predator. Accordingly, evidence for additive multiple predator interactions was found. 4. The lack of predator–predator interference between cyclopoid copepods and larval chaoborid midges provides strong support for their combined application in mosquito biocontrol. It is proposed that there should be increased examination of multiple predator effects in assessments of natural enemy efficacies to better understand overall predatory effects within communities and utilities in vector control. [ABSTRACT FROM AUTHOR]

Context: Despite so many efforts to control dengue, the disease has a huge impact on the health, well-being, and economy of the population. The key success to control dengue depends not only on services provided by health authorities but also on the awareness of the community about preventing practices and their health-seeking behavior. Hence, the present study was conducted to assess the awareness regarding dengue and its determinants among urban adult population of Rohtak. Aims: To assess the awareness regarding dengue and its determinants among urban adult population of Rohtak. Settings and Design: A cross-sectional study. Methods and Materials: Data were collected using a pretested, semi-structured interview schedule from 210 participants which included information on the demographic profile of the subject, awareness about the symptoms, transmission, vector behavior in terms of biting time and breeding places, preventive measures and treatment of dengue fever, and responsibility of vector control. Cumulative awareness was calculated on the basis of correct answers provided. Statistical Analysis Used: Categorical data were presented as a percentage. Pearson's Chi-square test was used to evaluate differences between groups for categorical variables. Results: The level of awareness was better among males (statistically significant). The difference in the level of awareness with respect to education, occupation, and the socioeconomic class was found highly statistically significant. Conclusions: Awareness regarding dengue and its preventive measures were specifically low in women; mostly housewives, in participants of the lower socioeconomic group, and those who were illiterate. [ABSTRACT FROM AUTHOR]

Existing research on household-level dengue impacts only assesses families of individuals with disease. However, behavioral and economic factors affect all households within an epidemic region. I assess changes in work hours among males and females in Iquitos, Peru, during intermittent dengue epidemics from 2005–2010. Epidemics are associated with large decreases in work hours for men and women who work. Females reduce hours more than males, and reduce hours when no household members report illness. The findings suggest that current government interventions aimed at reducing transmission during epidemics may inadvertently deter labor market activity. This research contributes to the infectious disease literature by separately assessing the impacts of epidemics on males and females in all households in an affected region. [ABSTRACT FROM AUTHOR]

We present an improved mathematical model of population dynamics of mosquito-borne disease transmission. Our model considers the effect of mosquito repellent use and the mosquito's behavior or attraction to the infected human, which cause mosquitoes' biased distribution around the human population. Our analysis of the model clearly shows the existence of thresholds for mosquito repellent efficacy and its utilization rate in the human population with respect to the elimination of mosquito-borne diseases. Further, the results imply that the suppression of mosquito-borne diseases becomes more difficult when the mosquitoes' distribution is biased to a greater extent around the human population. [ABSTRACT FROM AUTHOR]

West Nile virus (WNv) is a mosquito-borne disease caused by Flavivirus. To investigate the combined effects of vertical transmission, temperature-dependent incubation periods and seasonality on the transmission of WNv, we develop a delay differential system with stage-structure and time-varying delays. We then derive the mosquito reproduction number R0V and basic reproduction number R0 and show that these two numbers serve as threshold parameters that determine whether WNv will spread. As an application, we conduct a case study for WNv transmission in Los Angeles County, California. We also carry out numerical simulations to identify the situations that require time-periodic delays. Moreover, we find that rising temperatures may potentially increase the risk of disease outbreaks. [ABSTRACT FROM AUTHOR]

Predicting the impact of natural disasters such as hurricanes on the transmission dynamics of infectious diseases poses significant challenges. In this paper, we put forward a simple modelling framework to investigate the impact of heavy rainfall events (HREs) on mosquito-borne disease transmission in temperate areas of the world such as the southern coastal areas of the USA. In particular, we explore the impact of the timing of HREs relative to the transmission season via analyses that test the sensitivity of HRE-induced epidemics to variation in the effects of rainfall on the dynamics of mosquito breeding capacity, and the intensity and temporal profile of human population displacement patterns. The recent Hurricane Harvey in Texas motivates the simulations reported. Overall, we find that the impact of vector-borne disease transmission is likely to be greater the earlier the HREs occur in the transmission season. Simulations based on data for Hurricane Harvey suggest that the limited impact it had on vector-borne disease transmission was in part because of when it occurred (late August) relative to the local transmission season, and in part because of the mitigating effect of the displacement of people. We also highlight key data gaps related to models of vector-borne disease transmission in the context of natural disasters. This article is part of the theme issue 'Modelling infectious disease outbreaks in humans, animals and plants: approaches and important themes'. This issue is linked with the subsequent theme issue 'Modelling infectious disease outbreaks in humans, animals and plants: epidemic forecasting and control'. [ABSTRACT FROM AUTHOR]

Of the 3,500 species of mosquitoes worldwide, only a small portion carry and transmit the mosquito-borne diseases (MBDs) that cause approximately half a million deaths annually worldwide. The most common exotic MBDs, such as malaria and dengue, are not currently established in Canada, in part because of our relatively harsh climate; however, this situation could evolve with climate change. Mosquitoes native to Canada may become infected with new pathogens and move into new regions within Canada. In addition, new mosquito species may move into Canada from other countries, and these exotic species may bring exotic MBDs as well. With high levels of international travel, including to locations with exotic MBDs, there will be more travel-acquired cases of MBDs. With climate change, there is the potential for exotic mosquito populations to become established in Canada. There is already a small area of Canada where exotic Aedes mosquitoes have become established although, to date, there is no evidence that these carry any exotic (or already endemic) MBDs. The increased risks of spreading MBDs, or introducing exotic MBDs, will need a careful clinical and public health response. Clinicians will need to maintain a high level of awareness of current trends, to promote mosquito bite prevention strategies, and to know the laboratory tests needed for early detection and when to report laboratory results to public health. Public health efforts will need to focus on ongoing active surveillance, public and professional awareness and mosquito control. Canadians need to be aware of the risks of acquiring exotic MBDs while travelling abroad as well as the risk that they could serve as a potential route of introduction for exotic MBDs into Canada when they return home. [ABSTRACT FROM AUTHOR]

There are currently over 80 species of mosquito endemic in Canada-although only a few of these carry pathogens that can cause disease in humans. West Nile virus, Eastern equine encephalitis virus and the California serogroup viruses (including the Jamestown Canyon and snowshoe hare viruses) are mosquito-borne viruses that have been found to cause human infections in North America, including in Canada. Over the last 20 years, the incidence of most of these endemic mosquito-borne diseases (MBD) has increased approximately 10% in Canada, due in large part to climate change. It is anticipated that both the mosquito lifecycle and virus transmission patterns will be affected by climate change, resulting in an increase in both the range and local abundance of several important mosquito species. Laboratory studies and mathematical modelling suggest that increased ambient temperatures, changes in precipitation and extreme weather events associated with climate change will likely continue to drive mosquito vector and MBD range expansion, increasing the duration of transmission seasons and leading to MBD-related epidemics. Furthermore, Canada's endemic MBDs have complex transmission cycles, involving multiple reservoir hosts (birds and mammals), multiple pathogens and multiple mosquito species-all of which may be sensitive to climate and other environmental changes, and making forecasting of potential emerging trends difficult. These expected climate-induced changes in mosquitoes and MBDs underline the need for continued (and expanded) surveillance and research to ensure timely and accurate evaluation of the risks to the public health of Canadians. [ABSTRACT FROM AUTHOR]

Understanding the geographic distribution of mosquito‐borne disease and mapping disease risk are important for prevention and control efforts. Mosquito‐borne viruses (arboviruses), such as West Nile virus (WNV), are highly dependent on environmental conditions. Therefore, the use of environmental data can help in making spatial predictions of disease distribution. We used geocoded human case data for 2004–2017 and population‐weighted control points in combination with multiple geospatial environmental data sets to assess the environmental drivers of WNV cases and to map relative infection risk in South Dakota, USA. We compared the effectiveness of (1) land cover and physiography data, (2) climate data, and (3) spectral data for mapping the risk of WNV in South Dakota. A final model combining all data sets was used to predict spatial patterns of disease transmission and characterize the associations between environmental factors and WNV risk. We used a boosted regression tree model to identify the most important variables driving WNV risk and generated risk maps by applying this model across the entire state. We found that combining multiple sources of environmental data resulted in the most accurate predictions. Elevation, late‐season humidity, and early‐season surface moisture were the most important predictors of disease distribution. Indices that quantified interannual variability of climatic conditions and land surface moisture were better predictors than interannual means. We suggest that combining measures of interannual environmental variability with static land cover and physiography variables can help to improve spatial predictions of arbovirus transmission risk. Plain Language Summary: West Nile virus, a disease transmitted by mosquitoes, is often considered a tropical disease. However, within the United States, the most cases per capita are reported in the northern Great Plains, with South Dakota having the highest rate. In this study, we combined human case data with satellite‐based Earth observations and other environmental data to highlight the places in South Dakota with high West Nile virus risk and identify their environmental characteristics. Areas in northeastern South Dakota, specifically in the northern James River Valley, had the highest West Nile virus risk. These high‐risk zones were associated with low‐lying pasturelands and poorly drained soils in areas with high year‐to‐year variability in climate and land surface moisture. Key Points: Integrating multiple types of geospatial data improves risk maps for West Nile virus transmissionElevation, land cover, soils, summer climate, and remotely sensed spring land surface moisture were associated with West Nile virus casesIndices measuring interannual variability of climate and land surface moisture were important predictors of West Nile virus risk [ABSTRACT FROM AUTHOR]

Zika virus (ZIKV) is a mosquito-borne flavivirus for which there are no vaccines or specific therapeutics. To find drugs active on the virus is a complex, expensive and time-consuming process. The prospect of drug repurposing, which consists of finding new indications for existing drugs, is an interesting alternative to expedite drug development for specific diseases. In theory, drug repurposing is also able to respond much more rapidly to a crisis than a classical drug discovery process. Consequently, the methodology is attractive for vector-borne diseases that can emerge or re-emerge worldwide with the risk to become pandemic quickly. Different drugs, showing various structures, have been repurposed to be used against ZIKV infection. They are reviewed in this study and the conditions for their potential use in practice are discussed. [ABSTRACT FROM PUBLISHER]

Mosquitoes are a nuisance and can transmit pathogens to humans and other animals, resulting in notable morbidity and mortality. Organized mosquito control programs conduct surveillance, source reduction, treatment of mosquito oviposition sites, and adulticiding to protect public health. However, in some regions, there has been a decline in county and municipal mosquito control programs, and homeowners increasingly contract with private mosquito control companies or address mosquito-related issues themselves at the household level. The extent to which these services are being used, the potential for mosquito and/or insecticide exposure around the home, and the access to these services by individuals of different socioeconomic categories are not known. We conducted regional (western, central, eastern) assessments of public perception and knowledge of mosquito control services in a variety of communities of different socioeconomic categories (low, moderate, high) and types (urban, suburban, rural) in 3 North Carolina counties. We also assessed the respondents' basic knowledge of mosquito-borne diseases. Most respondents thought mosquito control was important to protect against both nuisance mosquitoes and mosquito-borne disease. The majority of people would pay ≤$50/year for mosquito control and most thought this should be covered by municipal/county taxes. Many respondents (31%, 95% confidence interval [CI] 26-35%) personally undertake mosquito control on their properties, but only 5.3% (95% CI 3.1-7.5%) contract with professional mosquito control services, with no significant differences between region, community type, or socioeconomic category in the proportion using private mosquito control services. While there were significant differences between factor levels (3 regions, 3 community types, 3 socioeconomic categories) in some responses, there were no significant differences observed between respondents, regardless of factor level, in the willingness to contribute funds to a community-based mosquito control program. [ABSTRACT FROM AUTHOR]

Health warnings of mosquito-borne disease risk require forecasts that are accurate at fine-temporal resolutions (weekly scales); however, most forecasting is coarse (monthly). We use environmental and Ross River virus (RRV) surveillance to predict weekly outbreak probabilities and incidence spanning tropical, semi-arid, and Mediterranean regions of Western Australia (1991-2014). Hurdle and linear models were used to predict outbreak probabilities and incidence respectively, using time-lagged environmental variables. Forecast accuracy was assessed by model fit and cross-validation. Residual RRV notification data were also examined against mitigation expenditure for one site, Mandurah 2007-2014. Models were predictive of RRV activity, except at one site (Capel). Minimum temperature was an important predictor of RRV outbreaks and incidence at all predicted sites. Precipitation was more likely to cause outbreaks and greater incidence among tropical and semi-arid sites. While variable, mitigation expenditure coincided positively with increased RRV incidence (r2 = 0·21). Our research demonstrates capacity to accurately predict mosquito-borne disease outbreaks and incidence at fine-temporal resolutions. We apply our findings, developing a user-friendly tool enabling managers to easily adopt this research to forecast region-specific RRV outbreaks and incidence. Approaches here may be of value to fine-scale forecasting of RRV in other areas of Australia, and other mosquito-borne diseases. [ABSTRACT FROM AUTHOR]

Health warnings of mosquito-borne disease risk require forecasts that are accurate at fine-temporal resolutions (weekly scales); however, most forecasting is coarse (monthly). We use environmental and Ross River virus (RRV) surveillance to predict weekly outbreak probabilities and incidence spanning tropical, semi-arid, and Mediterranean regions of Western Australia (1991-2014). Hurdle and linear models were used to predict outbreak probabilities and incidence respectively, using time-lagged environmental variables. Forecast accuracy was assessed by model fit and cross-validation. Residual RRV notification data were also examined against mitigation expenditure for one site, Mandurah 2007-2014. Models were predictive of RRV activity, except at one site (Capel). Minimum temperature was an important predictor of RRV outbreaks and incidence at all predicted sites. Precipitation was more likely to cause outbreaks and greater incidence among tropical and semi-arid sites. While variable, mitigation expenditure coincided positively with increased RRV incidence (r 2 = 0·21). Our research demonstrates capacity to accurately predict mosquito-borne disease outbreaks and incidence at fine-temporal resolutions. We apply our findings, developing a user-friendly tool enabling managers to easily adopt this research to forecast region-specific RRV outbreaks and incidence. Approaches here may be of value to fine-scale forecasting of RRV in other areas of Australia, and other mosquito-borne diseases. [ABSTRACT FROM AUTHOR]

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During recent months, there has been growing international public concern about the Zika virus. As scientific understanding of the Zika virus unfolds, there are still many unanswered questions. Public health officials, clinicians, and consumers alike have questions about the Zika virus and the Zika virus disease. There is a need to know where to turn for the most up-to-date and reliable online information sources. Although aspects of Zika virus disease and associated medical conditions can be frightening, information seekers may find reassurance in the following online sources to guide their understanding of risk, prevention, transmission, affected geographical areas, symptoms, and disease management. [ABSTRACT FROM PUBLISHER]

Context: Mosquito-borne diseases in the United States are notorious for their seemingly erratic temporal and spatial outbreak patterns in humans. Identifying linkages between fine-scale phenomenon and macroscale outbreak patterns can improve the understanding of these complex socio-ecological systems. Objectives: Using West Nile virus (WNV) as a model system, we examine whether fine-scale wetland characteristics-wetland size, connectivity, and inundation regime-have an important effect on macroscale human disease outbreak in the northeastern and midwestern United States. Methods: We take a spatially explicit GIS-based approach, derive new macroscale wetland metrics based on fine-scale wetland characteristics, and use county-level annual human WNV incidence data over 11 years to evaluate linkages between the fine and macroscales (1.6 million km). Results: In regions dominated by the Culex tarsalis WNV vector, U.S. counties with a small average wetland size had more than 100 % higher human WNV incidence than counties with a large average wetland size. In regions dominated by the Cx. pipiens and Cx. restuans vectors, a low proportional area of connected wetland was associated with at least 50 % higher human WNV incidence than a high proportional area of connected wetland. Finally, Cx. tarsalis-dominated counties with a high proportional area of semi-permanent wetland that were experiencing drought conditions had over 300 % higher annual WNV incidence than drought-affected counties with a low proportional area of semi-permanent wetland. Conclusions: Our results suggest that phenomena occurring at the individual wetland scale may aggregate to influence macroscale human WNV outbreak patterns and may be mediated by the interplay of other factors such as vector species-specific traits and climate. [ABSTRACT FROM AUTHOR]

Mosquitoes (Diptera: Culicidae) serve as important vectors for a wide number of parasites and pathogens of huge medical and veterinary importance. Aedes aegypti is a primary dengue vector in tropical and subtropical urban areas. There is an urgent need to develop eco-friendly mosquitocides. In this study, silver nanoparticles (AgNP) were biosynthesized using neem cake, a by-product of the neem oil extraction from the seed kernels of Azadirachta indica. AgNP were characterized using a variety of biophysical methods, including UV-vis spectrophotometry, FTIR, SEM, EDX, and XRD analyses. Furthermore, the neem cake extract and the biosynthesized AgNP were tested for acute toxicity against larvae and pupae of the dengue vector Ae. aegypti. LC values achieved by the neem cake extract ranged from 106.53 (larva I) to 235.36 ppm (pupa), while AgNP LC ranged from 3.969 (larva I) to 8.308 ppm (pupa). In standard laboratory conditions, the predation efficiency of a Carassius auratus per day was 7.9 (larva II) and 5.5 individuals (larva III). Post-treatment with sub-lethal doses of AgNP, the predation efficiency was boosted to 9.2 (larva II) and 8.1 individuals (larva III). The genotoxic effect of AgNP was studied on C. auratus using the comet assay and micronucleus frequency test. DNA damage was evaluated on peripheral erythrocytes sampled at different time intervals from the treatment; experiments showed no significant damages at doses below 12 ppm. Overall, this research pointed out that neem cake-fabricated AgNP are easy to produce, stable over time, and can be employed at low dosages to reduce populations of dengue vectors, with moderate detrimental effects on non-target mosquito natural enemies. [ABSTRACT FROM AUTHOR]

Dengue is a mosquito-borne viral disease that has rapidly spread in all regions of the world in recent years. Female mosquitoes, mainly Aedes aegypti, transmit dengue. Approximately 3,900 million people, in 128 countries, are at risk of dengue infection. Recently, a focus has been provided on the potential of green-synthesized nanoparticles as inhibitors of the production of dengue viral envelope (E) protein in Vero cells and downregulators of the expression of dengue viral E gene. Algae are an outstanding reservoir of novel compounds, which may help in the fight against mosquito-borne diseases. In this research, silver nanoparticles (AgNP) were rapidly synthesized using a cheap extract of the alga Centroceras clavulatum. AgNP were characterized by UV-vis spectrophotometry, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). In mosquitocidal assays, LC values of C. clavulatum extract against A. aegypti larvae and pupae were 269.361 ppm (larva I), 309.698 ppm (larva II), 348.325 ppm (larva III), 387.637 ppm (larva IV), and 446.262 ppm (pupa). C. clavulatum extract also exhibited moderate antioxidant activity, both in 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO) radical scavenging assays. LC values of C. clavulatum-synthesized AgNP were 21.460 ppm (larva I), 23.579 ppm (larva II), 25.912 ppm (larva III), 29.155 ppm (larva IV), and 33.877 ppm (pupa). Furthermore, C. clavulatum-synthesized AgNP inhibited dengue (serotype dengue virus type-2 (DEN-2)) viral replication in Vero cells. Notably, 50 μg/ml of green-synthesized AgNP showed no cytotoxicity on Vero cells while reduced DEN-2 viral growth of more than 80 %; 12.5 μg/ml inhibited viral growth of more than 50 %. Cellular internalization assays highlighted that untreated infected cells showed high intensity of fluorescence emission, which denotes high level of viral internalization. Conversely, AgNP-treated infected cells showed reduced levels of fluorescence, failing to show significant viral load. Overall, our study showed that alga-mediated synthesis of metal nanoparticles may be considered to develop newer, safer, and cheap tools in the fight against the dengue virus, serotype DEN-2, and its vector A. aegypti, with little cytotoxicity on mammalian cells. [ABSTRACT FROM AUTHOR]

Mosquito-borne diseases cause significant public health burden and are widely re-emerging or emerging. Understanding, predicting, and mitigating the spread of mosquito-borne disease in diverse populations and geographies are ongoing modelling challenges. We propose a hybrid network-patch model for the spread of mosquito-borne pathogens that accounts for individual movement through mosquito habitats, extending the capabilities of existing agent-based models (ABMs) to include vector-borne diseases. The ABM are coupled with differential equations representing ‘clouds’ of mosquitoes in patches accounting for mosquito ecology. We adapted an ABM for humans using this method and investigated the importance of heterogeneity in pathogen spread, motivating the utility of models of individual behaviour. We observed that the final epidemic size is greater in patch models with a high risk patch frequently visited than in a homogeneous model. Our hybrid model quantifies the importance of the heterogeneity in the spread of mosquito-borne pathogens, guiding mitigation strategies. [ABSTRACT FROM PUBLISHER]

We study a mosquito-borne epidemic model where the vector population is distinct in aquatic and adult stages and a saturating effect of disease transmission is assumed to occur when the population of infectious carriers becomes large enough. A qualitative analysis, including centre manifold analysis, has been performed to determine the existence of stability-instability thresholds. [ABSTRACT FROM AUTHOR]