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The global shipping network (GSN) has been suggested as a pathway for the establishment and reintroduction of Aedes aegypti and Aedes albopictus primarily via the tire trade. We used historical maritime movement data in combination with an agent-based model to understand invasion risk in the United States Gulf Coast and how the risk of these invasions could be reduced. We found a strong correlation between the total number of cargo ship arrivals at each port and likelihood of arrival by both Ae. aegypti and Ae. albopictus. Additionally, in 2012, 99.2% of the arrivals into target ports had most recently visited ports likely occupied by both Ae. aegypti and Ae. albopictus, increasing risk of Aedes invasion. Our model results indicated that detection and removal of mosquitoes from containers when they are unloaded effectively reduced the probability of mosquito populations establishment even when the connectivity of ports increased. To reduce the risk of invasion and reintroduction of Ae. aegypti and Ae. albopictus, surveillance and control efforts should be employed when containers leave high risk locations and when they arrive in ports at high risk of establishment. Author summary: Our study investigates how the global shipping network inadvertently serves as a highway for the spread of two mosquito species, Aedes aegypti and Aedes albopictus, both of which are vectors for pathogens causing diseases like dengue and Zika. We analyzed maritime movement data in the United States Gulf Coast and found that the more cargo ships that dock at a port, the higher the chance these mosquitoes will be introduced; nearly all cargo ships arriving at these ports had last visited regions where these mosquitoes thrive, significantly raising the risk of spread of these mosquitoes. Our research also suggested that proactive detection and elimination of mosquitoes from shipping containers can dramatically lower the risk of these pests establishing new colonies, even as global shipping traffic grows. Our work suggests that by enhancing surveillance and control measures at strategic points in the shipping process, we can safeguard our communities from additional mosquito introductions. [ABSTRACT FROM AUTHOR]

Locally acquired malaria is rare in the US; however, in 2023, cases were reported in Florida, Texas, Maryland, and Arkansas. Prompt diagnosis and treatment of malaria are essential to prevent severe malaria disease. This article details malaria and offers treatment guidelines. [ABSTRACT FROM AUTHOR]

Chikungunya virus (CHIKV) is an alphavirus that has re‐emerged globally over the last two decades and has the potential to become endemic in the United States due to the presence of competent mosquito vectors, Aedes aegypti and Aedes albopictus. CHIK disease is characterised by fever, rash, and joint pain, and causes chronic debilitating joint pain and swelling in >50% of infected individuals. Given the disease severity caused by CHIKV and the global presence of vectors to facilitate its spread, strategies to reduce viral transmission are desperately needed; however, the human biological factors driving CHIKV transmission are poorly understood. Towards that end, we have previously shown that mosquitoes fed on alphavirus‐infected obese mice have reduced infection and transmission rates compared to those fed on infected lean mice despite similar viremia in lean and obese mice. One of the many host factors that increase in obese hosts is insulin, which was previously shown to impact the infection of mosquitoes by several flaviviruses. However, insulin's impact on alphavirus infection of live mosquitoes is unknown and whether insulin influences mosquito‐borne virus transmission has not been tested. To test this, we exposed A. aegypti mosquitoes to bloodmeals with CHIKV in the presence or absence of physiologically relevant levels of insulin and found that insulin significantly lowered both infection and transmission rates. RNA sequencing analysis on mosquito midguts isolated at 1‐day‐post‐infectious‐bloodmeal (dpbm) showed enrichment in genes in the Toll immune pathway in the presence of insulin, which was validated by reverse transcription‐quantitative polymerase chain reaction (RT‐qPCR). We then sought to determine if the Toll pathway plays a role in CHIKV infection of Ae. aegypti mosquitoes; therefore, we knocked down Myd88, a critical immune adaptor molecule for the Toll pathway, in live mosquitoes, and found increased CHIKV infection compared to the mock knockdown control group. Overall, these data demonstrate that insulin reduces CHIKV transmission by Ae. aegypti and activates the Toll pathway in mosquitoes, suggesting that conditions resulting in higher serum insulin concentrations may reduce alphavirus transmission. Finally, these studies suggest that strategies to activate insulin or Toll signalling in mosquitoes may be an effective control strategy against medically relevant alphaviruses. [ABSTRACT FROM AUTHOR]

Microaggressions are sometimes compared to “mosquito bites,” considering their subtle nature. It seems like an overreaction if someone fights against those “mosquitos.” However, these “bites” are often extremely stressful and demoralizing and result in severe depression. Through the lenses of intersectionality, this study explored the microaggression experiences and negotiation strategies of Chinese international graduate students (CIGS) in a predominantly White institution in the US. Findings revealed that prominent microaggressions, which had a major role in CIGS’ high anxiety level and low confidence, were related to language and social interaction barriers. However, most CIGS tended to internalize the suppressions as a mechanism for survival and resistance. The findings of the study expose inequities, prejudices, and marginalization for minority international students and offer suggestions for stakeholders to create a supportive and inclusive campus environment consciously. [ABSTRACT FROM AUTHOR]

Aims Garden cress (Lepidium sativum L.), a member of the Cruciferae family, is widely planted worldwide, especially in India, Europe, and the United States. One of the most common mosquito species that carries Plasmodium falciparum is the Anopheles gambiae sensu lato, which may be combated by sprinkling fields with Lepidium sativum seeds. This study aimed to test the Lepidium sativum Linn. seeds extract as an antimicrobial agent against food pathogens. Materials & Methods The active components were extracted from the powdered dry seeds using chloroform, ethyl acetate, methanol, and dichloromethane. The antibacterial activity of various doses of the extracts was evaluated using agar well diffusion. The MIC and MBC for the most effective extract were estimated using tube dilution and subculturing methods. Findings Staphylococcus aureus had an MIC of 1.56mg/ml and a minimum inhibitory concentration (MBC) of 6.52mg/ml, while Salmonella typhi had an MIC of 25mg/ml. At a concentration of 10% L. sativum, the half-life (KDT50) was determined to be 7.34 minutes. Conversely, the half-life of L. sativum oil was only 10.05 minutes when used at the same concentration. Compared to the L. sativum concentrations that resulted in the KDT50 (50 and 10%, respectively), the bendiocarb 0.1% impregnated filter paper performed poorly. Conclusion L. sativum essential oil effectively kills Anopheles gambiae. [ABSTRACT FROM AUTHOR]

Background The Florida Keys Mosquito Control District utilises dry ice-baited light traps to monitor mosquito populations on Key Largo, Florida. This paper describes the methodology of trapping, habitat description and dataset of adult mosquito populations from 18 years of weekly monitoring from a single site on Key Largo, Monroe County, Florida, USA. New information This paper details a previously unreported dataset derived from trap collections made on Key Largo, Florida at a site designated as “Gun Club Road.” [ABSTRACT FROM AUTHOR]

Background The Florida Keys Mosquito Control District has used dry ice-baited light traps to monitor mosquito populations on Key Largo since 2003. This paper describes the methodology of trapping, the habitat and the dataset of adult mosquito populations from 18 years of weekly monitoring from a single site on Key Largo, Monroe County, FL, USA. New information This data paper provides previously unpublished data from a single trapping location in Key Largo, Florida. Two new species have been added to previously-published data from this trapping site. [ABSTRACT FROM AUTHOR]

New introductions to invasive mosquitoes, Aedes aegypti and Aedes albopictus, increase the risk for vector-borne diseases such as dengue, chikungunya, and Zika in the United States. Tracking these new introductions is more important than ever. This lesson plan focuses on the collection of mosquito larvae and pupae before the onset of summer with a focus on insect development. Students will observe the immature mosquitoes grow and metamorphose into adults. Novel aspects include collecting larvae and pupae around the home/school, observing the mosquito life cycle by safely rearing them from immature stages (larvae and pupae) to adults, and learning important background information on mosquito biology and pathogens that mosquitoes can transmit. The lesson describes new tools to use with the Invasive Mosquito Project, an international citizen science–based mosquito surveillance program exploring mosquitoes and the pathogens they may transmit to interested community members (including students and teachers) and their companion animals. This project is a stand-alone or follow-up lesson plan to the mosquito egg collection lesson used prior to the onset of winter (see Cohnstaedt et al., 2016). Students are able to participate in a hands-on tutorial to build a sealed emergence chamber to safely raise mosquitoes. Long-term data sets can also be used by teachers and students for further classroom discussions on the risks of mosquito-borne illnesses nationwide. This lesson further focuses on how individuals must play an active role in protecting their communities and pets from illness and increasing awareness of the dangerous pathogens mosquitoes can transmit and the importance of mosquito management. Materials from this lesson plan (available at http://www.citizenscience.us) can be adapted for each classroom but are best-suited for middle school to high school classes, as well as Advanced Placement classes. [ABSTRACT FROM AUTHOR]

We present artificial neural networks as a feasible replacement for a mechanistic model of mosquito abundance. We develop a feed-forward neural network, a long short-term memory recurrent neural network, and a gated recurrent unit network. We evaluate the networks in their ability to replicate the spatiotemporal features of mosquito populations predicted by the mechanistic model, and discuss how augmenting the training data with time series that emphasize specific dynamical behaviors affects model performance. We conclude with an outlook on how such equation-free models may facilitate vector control or the estimation of disease risk at arbitrary spatial scales. Author summary: Aedes aegypti mosquitoes affect millions of people each year through infectious diseases such as chikungunya, dengue, and Zika. Because local vector levels need to be sufficiently high for associated outbreaks to occur, the ability to estimate mosquito abundance is a central component of assessing disease risk. The mosquito landscape model (MoLS) is a mechanistic model that estimates Aedes aegypti abundance from local weather time series, and is able to reproduce trends observed in surveillance data. However, scaling this up to a large number of locations is resource intensive, requiring a high-performance computing system. In this article, we develop artificial neural network models that are significantly faster than MoLS and can produce abundance estimates directly from local weather data. This approach reduces the computational time associated with estimating local mosquito levels, thereby allowing for a corresponding increase in the spatiotemporal resolution of these predictions. We compare network design choices, including architecture and training data, in their ability to accurately reproduce MoLS estimates and analyze model performance in locations across the contiguous United States. [ABSTRACT FROM AUTHOR]

Organized mosquito control programs (MCP) in the United States have been protecting public health since the early 1900s. These programs utilize integrated mosquito management for surveillance and control measures to enhance quality of life and protect the public from mosquito-borne diseases. Because much of the equipment and insecticides are developed for agriculture, MCP are left to innovate and adapt what is available to accomplish their core missions. Unmanned aerial systems (UAS) are one such innovation that are quickly being adopted by MCP. The advantages of UAS are no longer conjectural. In addition to locating mosquito larval habitats, UAS affords MCP real-time imagery, improved accuracy of aerial insecticide applications, mosquito larval detection and sampling. UAS are also leveraged for applying larvicides to water in habitats that range in size from multi-acre wetlands to small containers in urban settings. Employing UAS can reduce staff exposure to hazards and the impact associated with the use of heavy equipment in sensitive habitats. UAS are utilized by MCP nationally and their use will continue to increase as technology advances and regulations change. Current impediments include a dearth of major UAS manufacturers of equipment that is tailor-made for mosquito control, pesticides that are optimized for application via UAS and regulations that limit the access of UAS to national airspace. This manuscript highlights the strengths and weaknesses of UAS within MCP, provides an update on systems and methods used, and charts the future direction of UAS technology within MCP tasked with public health protection. [ABSTRACT FROM AUTHOR]

• The first locally acquired malaria cases in the United States in 20 years occurred in 2023. • The risk of malaria transmission in the US is low but may increase as climate change influences the habitable range of Anopheles mosquitos. • The recent occurrence of locally acquired malaria in the US highlights the importance of continued surveillance in the era of climate change. [ABSTRACT FROM AUTHOR]

The mosquito, Culex tarsalis, is a key vector in the western United States due to its role in transmission of zoonotic arboviruses that affect human health. Extensive research has been conducted on Cx. tarsalis ecology, feeding behavior, vector competence, autogeny, diapause, genetics, and insecticide resistance. Population genetic analyses in the western U.S. have identified at least three genetic clusters that are geographically distinct. However, in-depth genetic studies have been hindered by the lack of a reference genome. In this study, we present the first whole-genome assembly of this mosquito species (CtarK1) based on PacBio HiFi reads from high-molecular-weight DNA extracted from a single male. The CtarK1 assembly is 790 Mb with an N50 of 58 kb, which is 27% larger than Culex quinquefasciatus (578Mb). This difference appears to be mostly composed of transposable elements. To annotate CtarK1, we used a previously assembled Cx. tarsalis transcriptome and approximately 17,456 protein genes from Cx. quinquefasciatus (N 1/4 17,456). Genome completeness was assessed using the Benchmarking Universal Single-Copy Orthologs (BUSCO) tool, which identified 84.8% of the 2799 Dipteran BUSCO genes. Using a Bayesian phylogeny based on mitochondrial genomes, we place Cx. tarsalis in the context of other mosquito species and estimate the divergence between Cx. tarsalis and Cx. quinquefasciatus to be between 15.8 and 22.2 million years ago (MYA). Important next steps from this work include characterizing the genetic basis of diapause and sex determination in Culex mosquitoes. [ABSTRACT FROM AUTHOR]

Mosquito control districts in the United States are limited to two main classes of adulticides, pyrethroids and organophosphates, to control mosquitoes. Two adulticides used to control domestic mosquitoes are Fyfanon EW (malathion, organophosphate) and DeltaGard (deltamethrin, pyrethroid). While the effect of these pesticides on European honeybees (Apis mellifera L. Hymenoptera: Apidae) has been investigated, effects on native pollinators need additional research. The purpose of this study was to investigate the acute nontarget effects of these pesticides on Bombus impatiens Cresson (Hymenoptera: Apidae), a native North American bumble bee species, and compare these effects to wild and laboratory strains of mosquitoes (Aedes aegypti (L.) and Culex quinquefasciatus Say, Diptera: Culicidae) through field and laboratory assays. Bombus impatiens was found to be resistant to Fyfanon EW (x̅ = 6.7% mortality at 50-µg malathion per bottle) at levels that caused significant mortality to study mosquitoes (86.2 ≥ x̅ ≥ 100% mortality) in laboratory bottle bioassays. Comparatively, B. impatiens demonstrated greater mortality to DeltaGard (93.3%) at 2.5-µg deltamethrin/bottle than any mosquito colony assayed (14.1 ≥ x̅ ≥ 87.0% mortality). Only DeltaGard was tested in field applications. In the field, we observed acute effects of DeltaGard on mosquitoes and B. impatiens at 25- and 75-m distance from a truck-mounted ultra-low volume fogger, although treatment effects were not significant for B. impatiens. Additional wild-caught nontarget mortality to DeltaGard field trials was also evaluated. This study indicated that common mosquito control adulticides do cause nontarget mortality to B. impatiens but that impacts are variable depending on pesticide and further studies are needed. [ABSTRACT FROM AUTHOR]

In temperate climates, the recurring seasonal exigencies of winter represent a fundamental physiological challenge for a wide range of organisms. In response, many temperate insects enter diapause, an alternative developmental program, including developmental arrest, that allows organisms to synchronize their life cycle with seasonal environmental variation. Geographic variation in diapause phenology contributing to local climatic adaptation is well documented. However, few studies have examined how the rapid evolution of a suite of traits expressed across the diapause program may contribute to climatic adaptation on a contemporary timescale. Here, we investigate the evolution of the diapause program over the past 35 years by leveraging a "natural experiment" presented by the recent invasion of the Asian tiger mosquito, Aedes albopictus, across the eastern United States. We sampled populations from two distinct climatic regions separated by 6° of latitude (∼700 km). Using common‐garden experiments, we identified regional genetic divergence in diapause‐associated cold tolerance, diapause duration, and postdiapause starvation tolerance. We also found regional divergence in nondiapause thermal performance. In contrast, we observed minimal regional divergence in nondiapause larval growth traits and at neutral molecular marker loci. Our results demonstrate rapid evolution of the diapause program and imply strong selection caused by differences in winter conditions. [ABSTRACT FROM AUTHOR]

BACKGROUND: Aedes aegypti and Ae. albopictus are mosquito vectors of more than 22 arboviruses that infect humans. OBJECTIVES: Our objective was to develop regional ecological niche models for Ae. aegypti and Ae. albopictus in the conterminous United States and Canada with current observed and simulated climate and land-use data using boosted regression trees (BRTs). METHODS: We used BRTs to assess climatic suitability for Ae. albopictus and Ae. aegypti mosquitoes in Canada and the United States under current and future projected climates. RESULTS: Models for both species were mostly influenced by minimum daily temperature and demonstrated high accuracy for predicting their geographic ranges under the current climate. The northward range expansion of suitable niches for both species was projected under future climate models. Much of the United States and parts of southern Canada are projected to be suitable for both species by 2100, with Ae. albopictus projected to expand its range north earlier this century and further north than Ae. aegypti. DISCUSSION: Our projections suggest that the suitable ecological niche for Aedes will expand with climate change in Canada and the United States, thus increasing the risk of Aedes-transmitted arboviruses. Increased surveillance for these vectors and the pathogens they carry would be prudent. [ABSTRACT FROM AUTHOR]

Based on the invasion of the Aedes albopictus mosquitoes and the competition between Ae. albopictus and Ae. aegypti mosquitoes in the United States, we consider a two-species competition model in a network, that is, with discrete Laplacian diffusion. In the case of weak-strong competition where the invasive competitor is stronger than the local one, it is shown that solutions converge uniformly to the semipositive equilibrium such that the invasive species survives while the local species becomes extinct, and vice versa. In the case of weak-weak competition, solutions converge uniformly to the positive equilibrium such that both invasive and local species coexist. By using numerical simulations, we apply the two-species competition model in a network to explain the invasion and competition of Ae. Albopictus and Ae. Aegypti mosquitoes in the United States. It also indicates that discrete Laplacian diffusion induces different spreading speeds in different invasive directions. [ABSTRACT FROM AUTHOR]

Background: In the northeast United States (U.S.), mosquitoes transmit a number of arboviruses, including eastern equine encephalitis, Jamestown Canyon, and West Nile that pose an annual threat to human and animal health. Local transmission of each arbovirus may be driven by the involvement of multiple mosquito species; however, the specificity of these vector-virus associations has not been fully quantified. Methodology: We used long-term surveillance data consistently collected over 18 years to evaluate mosquito and arbovirus community composition in the State of Connecticut (CT) based on land cover classifications and mosquito species-specific natural histories using community ecology approaches available in the R package VEGAN. We then used binomial-error generalized linear mixed effects models to quantify species-specific trends in arbovirus detections. Primary results: The composition of mosquito communities throughout CT varied more among sites than among years, with variation in mosquito community composition among sites explained mostly by a forested-to-developed-land-cover gradient. Arboviral communities varied equally among sites and years, and only developed and forested wetland land cover classifications were associated with the composition of arbovirus detections among sites. Overall, the avian host arboviruses, mainly West Nile and eastern equine encephalitis, displayed the most specific associations among mosquito species and sites, while in contrast, the mammalian host arboviruses (including Cache Valley, Jamestown Canyon, and Potosi) associated with a more diverse mix of mosquito species and were widely distributed throughout CT. Conclusions: We find that avian arboviruses act as vector specialists infecting a few key mosquito species that associate with discrete habitats, while mammalian arboviruses are largely vector generalists infecting a wide diversity of mosquito species and habitats in the region. These distinctions have important implications for the design and implementation of mosquito and arbovirus surveillance programs as well as mosquito control efforts. Author summary: The numbers and types of mosquito species in a community vary across space and time, and this variability may be linked to variation in risk of human exposure to mosquito-borne diseases. In this report, the authors use a long-term mosquito-borne virus (i.e., arbovirus) surveillance dataset from the State of Connecticut (CT), United States to first examine whether or not the same land cover classes explain variation in mosquito and arbovirus community composition; they then used statistical models to determine which mosquito species were the most likely and unlikely to test positive for an infection for one of seven arboviruses circulating in CT. Multiple mosquito species tested positive for each arbovirus examined, and blood feeding behaviors were the strongest predictor of whether or not a mosquito species tested positive for a particular arbovirus. Isolations of bird-host arboviruses aggregated in discrete habitat types, while isolations of mammalian-host arboviruses showed no specific habitat associations. The authors conclude that risk of bird-host arbovirus exposures in humans is driven by only a few key mosquito species, whereas risk of mammalian-host arbovirus exposure in humans could be attributed to the general presence and abundance of mammal-feeding mosquito species in the community. [ABSTRACT FROM AUTHOR]

Rapid adaptation in response to novel environments can facilitate species invasions and range expansions. Understanding how invasive disease vectors rapidly evolve to novel conditions—particularly at the edge of its non‐native range—has important implications for mitigating the prevalence and spread of disease.Here, we evaluate the role of local adaptation in overwintering capability of the Asian tiger mosquito, Aedes albopictus. This species invaded the Southern United States in the 1980s and rapidly spread northward into novel climate compared to its native range. Photoperiodically induced egg diapause is a key trait contributing to the establishment and spread of Ae. albopictus in temperate latitudes, and diapause incidence rapidly developed a cline along a latitudinal gradient in the United States shortly after its initial invasion. However, variation in overwintering survival of diapause‐induced eggs along this gradient is not known, but is critical to the fitness‐related role of diapause evolution in the establishment of Ae. albopictus in its northern US range.Using reciprocal transplants, we detected local adaptation in overwinter survival of diapausing Aedes albopictus eggs. In northern range‐edge winters, eggs produced by range‐edge individuals survived better than those produced by range‐core individuals. Diapause eggs from range‐edge and range‐core locations survived equally well in range‐core winters, and no eggs survived a winter beyond the current northern range limit in the United States.Synthesis and applications. These results demonstrate rapid (~3 decades) local adaptation of egg diapause, a key trait facilitating overwinter survival and range expansion for the invasive Asian tiger mosquito. In light of these results, control efforts could shift from targeting satellite populations to a focus on preventing dispersal into locally adapted, range‐edge locations and to aim removal efforts towards areas surrounding locally adapted populations. Adopting new approaches to target rapidly adapting populations will require large‐scale collaboration among control agencies and research institutions, and should begin in the northern US range to better control Aedes albopictus mosquito populations in the face of rapid adaptation. [ABSTRACT FROM AUTHOR]

Aedes (Stegomyia) aegypti (L.) and Ae. (Stegomyia) albopictus (Skuse) mosquitoes can transmit dengue, chikungunya, yellow fever, and Zika viruses. Limited surveillance has led to uncertainty regarding the geographic ranges of these vectors globally, and particularly in regions at the present-day margins of habitat suitability such as the contiguous United States. Empirical habitat suitability models based on environmental conditions can augment surveillance gaps to describe the estimated potential species ranges, but model accuracy is unclear. We identified previously published regional and global habitat suitability models for Ae. aegypti (n = 6) and Ae. albopictus (n = 8) for which adequate information was available to reproduce the models for the contiguous U.S. Using a training subset of recently updated county-level surveillance records of Ae. aegypti and Ae. albopictus and records of counties conducting surveillance, we constructed accuracy-weighted, probabilistic ensemble models from these base models. To assess accuracy and uncertainty we compared individual and ensemble model predictions of species presence or absence to both training and testing data. The ensemble models were among the most accurate and also provided calibrated probabilities of presence for each species. The quantitative probabilistic framework enabled identification of areas with high uncertainty and model bias across the U.S. where improved models or additional data could be most beneficial. The results may be of immediate utility for counties considering surveillance and control programs for Ae. aegypti and Ae. albopictus. Moreover, the assessment framework can drive future efforts to provide validated quantitative estimates to support these programs at local, national, and international scales. [ABSTRACT FROM AUTHOR]

The construction industry employs millions of workers in the USA. However, little is known about how environmental disturbances caused by the construction industry impacts vector mosquito ecology and behavior, and whether it is responsible for increasing the abundance of mosquitoes. There is a major scientific gap on how to assess the occupational exposure risk of mosquito biting and arbovirus transmission among outdoor worker populations who spend a disproportionate amount of time working outdoors. In our opinion, it is critical to address how construction workers and the surrounding communities may be geographically and seasonally exposed to vector mosquitoes. Research should identify modifiable worker- and organizational-level factors that improve worksite mosquito-control practices to give insights into future vector-control strategies in urban environments. Recent studies have shown that the proliferation of vector mosquitoes is partially attributable to construction sites. Very little is known about how environmental disturbances caused by construction sites impact vector mosquito ecology and behavior. There is a significant scientific gap on how to assess the risk of mosquito biting and arbovirus transmission in construction sites. In our opinion, it is critical to address how construction sites may be geographically and seasonally exposed to vector mosquitoes and their effect on the transmission of arboviruses in the surrounding communities and in the population as a whole. Research should also identify modifiable worker- and organizational-level factors that improve mosquito-control practices to guide future vector-control strategies in urban environments. [ABSTRACT FROM AUTHOR]

Resistance to insecticides can hamper the control of mosquitoes such as Culex quinquefasciatus, known to vector arboviruses such as West Nile virus and others. The strong selective pressure exerted on a mosquito population by the use of insecticides can result in heritable genetic changes associated with resistance. We sought to characterize genetic differences between insecticide resistant and susceptible Culex quinquefasciatus mosquitoes using targeted DNA sequencing. To that end, we developed a panel of 122 genes known or hypothesized to be involved in insecticide resistance, and used an Ion Torrent PGM sequencer to sequence 125 unrelated individuals from seven populations in the southern U.S. whose resistance phenotypes to permethrin and malathion were known from previous CDC bottle bioassay testing. Data analysis consisted of discovering SNPs (Single Nucleotide Polymorphism) and genes with evidence of copy number variants (CNVs) statistically associated with resistance. Ten of the seventeen genes found to be present in higher copy numbers were experimentally validated with real-time PCR. Of those, six, including the gene with the knock-down resistance (kdr) mutation, showed evidence of a ≥ 1.5 fold increase compared to control DNA. The SNP analysis revealed 228 unique SNPs that had significant p-values for both a Fisher’s Exact Test and the Cochran-Armitage Test for Trend. We calculated the population frequency for each of the 64 nonsynonymous SNPs in this group. Several genes not previously well characterized represent potential candidates for diagnostic assays when further validation is conducted. [ABSTRACT FROM AUTHOR]

Arthropod vector feeding preferences are defined as an overutilization of a particular host species given its abundance in relationship to other species in the community. Numerous methods exist to quantify vector feeding preferences; however, controlled host choice experiments are generally an underutilized approach. In this report, we present results from controlled vector host choice experiments using Culex quinquefasciatus Say (Diptera: Culicidae) mosquitoes and wild avian hosts identified as important contributors to West Nile virus (WNv) transmission in Atlanta, Georgia, United States. In each experiment, we allowed lab-reared F1Cx. quinquefasciatus to feed freely overnight on two avian individuals of a different species (i.e., northern cardinals, American robins, blue jays, brown thrashers, and gray catbirds). We then estimated WNv transmission potential using vectorial capacity and R0. We found that mosquito blood feeding success was extremely variable among experimental replicates and that patterns of host choice only occasionally aggregated to a particular bird species. Vectorial capacity was highest for American robins and blue jays due to these species' higher reservoir competence for WNv and greater probabilities of mosquito selection of these species. Despite species-specific differences in vectorial capacity, total community capacity was similar among species pairs. R0 estimates were qualitatively similar to capacity, and R0 was below and above unity across species pairs. Our results provide empirical evidence that C. quinquefasciatus is an opportunistic blood feeder and highlight how variability in vector–host contact rates as well as host community composition can influence the likelihood of WNv transmission in avian communities. [ABSTRACT FROM AUTHOR]

Everglades virus (EVEV), subtype II within the Venezuelan equine encephalitis (VEE) virus complex, is a mosquitoborne zoonotic pathogen endemic to south Florida, USA. EVEV infection in humans is considered rare, probably because of the sylvatic nature of the vector, the Culex (Melanoconion) cedecei mosquito. The introduction of Cx. panocossa, a tropical vector mosquito of VEE virus subtypes that inhabits urban areas, may increase human EVEV exposure. Field studies investigating spatial and temporal patterns of abundance, host use, and EVEV infection of Cx. cedecei mosquitoes in Everglades National Park found that vector abundance was dynamic across season and region. Rodents, particularly Sigmodon hispidus rats, were primary vertebrate hosts, constituting 77%-100% of Cx. cedecei blood meals. Humans were fed upon at several locations. We detected EVEV infection in Cx. cedecei mosquitoes in lower and upper regions of Everglades National Park only during the wet season, despite an abundance of Cx. cedecei mosquitoes at other sampling times. [ABSTRACT FROM AUTHOR]

Context: Socioeconomic and landscape factors influence mosquito abundance especially in urban areas. Few studies addressed how socioeconomic and landscape factors, especially at micro-scale for mosquito life history, determine mosquito abundance. Objectives: We aim to predict mosquito abundance based on socioeconomic and/or landscape factors using machine learning framework. Additionally, we determine these factors' response to mosquito abundance. Methods: We identified 3985 adult mosquitoes (majority of which were Aedes mosquitoes) in 90 sampling sites from Charlotte, NC, USA in 2017. Seven socioeconomic and seven landscape factors were used to predict mosquito abundance. Three supervised learning models, k-nearest neighbor (kNN), artificial neural network (ANN), and support vector machine (SVM) were constructed, tuned, and evaluated using both continuous input factors and binary inputs. Random forest (RF) was used to assess individual input's relative importance and response to mosquito abundance. Results: We showed that landscape factors alone yielded equal or better predictability than socioeconomic factors. The inclusion of both types of factors further improved model accuracy using binary inputs. kNN also had robust performance regardless of inputs (accuracy > 95% for binary and > 99% for continuous input data). Landscape factors group had higher importance than socioeconomic group (54.4% vs. 45.6%). Landscape heterogeneity (measured by Shannon index) was the single most important input factor for mosquito abundance. Conclusions: Landscape factors were the key for mosquito abundance. Machine learning models were powerful tools to handle complex datasets with multiple socioeconomic and landscape factors to accurately predict mosquito abundance. [ABSTRACT FROM AUTHOR]

The maximum entropy model, a commonly used species distribution model (SDM) normally combines observations of the species occurrence with environmental information to predict the geographic distributions of animal or plant species. However, it only produces point estimates for the probability of species existence. To understand the uncertainty of the point estimates, we analytically derived the variance of the outputs of the maximum entropy model from the variance of the input. We applied the analytic method to obtain the standard deviation of dengue importation probability and Aedes aegypti suitability. Dengue occurrence data and Aedes aegypti mosquito abundance data, combined with demographic and environmental data, were applied to obtain point estimates and the corresponding variance. To address the issue of not having the true distributions for comparison, we compared and contrasted the performance of the analytical expression with the bootstrap method and Poisson point process model which proved of equivalence of maximum entropy model with the assumption of independent point locations. Both Dengue importation probability and Aedes aegypti mosquito suitability examples show that the methods generate comparatively the same results and the analytic method we introduced is dramatically faster than the bootstrap method and directly apply to maximum entropy model. [ABSTRACT FROM AUTHOR]

Control of arbovirus transmission remains focused on vector control through application of insecticides directly to the environment. However, these insecticide applications are often reactive interventions that can be poorly-targeted, inadequate for localized control during outbreaks, and opposed due to environmental and toxicity concerns. In this study, we developed endectocide-treated feed as a systemic endectocide for birds to target blood feeding Culex tarsalis, the primary West Nile virus (WNV) bridge vector in the western United States, and conducted preliminary tests on the effects of deploying this feed in the field. In lab tests, ivermectin (IVM) was the most effective endectocide tested against Cx. tarsalis and WNV-infection did not influence mosquito mortality from IVM. Chickens and wild Eurasian collared doves exhibited no signs of toxicity when fed solely on bird feed treated with concentrations up to 200 mg IVM/kg of diet, and significantly more Cx. tarsalis that blood fed on these birds died (greater than 80% mortality) compared to controls (less than 25% mortality). Mosquito mortality following blood feeding correlated with IVM serum concentrations at the time of blood feeding, which dropped rapidly after the withdrawal of treated feed. Preliminary field testing over one WNV season in Fort Collins, Colorado demonstrated that nearly all birds captured around treated bird feeders had detectable levels of IVM in their blood. However, entomological data showed that WNV transmission was non-significantly reduced around treated bird feeders. With further development, deployment of ivermectin-treated bird feed might be an effective, localized WNV transmission control tool. [ABSTRACT FROM AUTHOR]

West Nile virus (WNV) has been circulating in California since its first detection in 2003, causing repeated outbreaks affecting public, wildlife and veterinary health. Epidemics of WNV are difficult to predict due to the multitude of factors influencing transmission dynamics among avian and mosquito hosts. Typically, high levels of WNV amplification are required for outbreaks to occur, and therefore associated viral strains may exhibit enhanced virulence and mortality in competent bird species resulting in increased mosquito infection prevalence. In our previous study, most WNV isolates made from California during 2007–08 showed increased fitness when competed in House Finches (HOFI, Haemorhous mexicanus) and Culex tarsalis Coquillett mosquitoes against COAV997-5nt, a genetically marked recombinant virus derived from a 2003 California strain. Herein, we evaluated the competitive fitness of WNV strains isolated during California epidemics in 2004, 2005, 2007, 2011 and 2012 against COAV997-5nt. These outbreak isolates did not produce elevated mortality in HOFIs, but replicated more efficiently than did COAV997-5nt based on quantification of WNV RNA copies in sera, thereby demonstrating increased competitive fitness. Oral co-infections in Cx. tarsalis resulted in similar virus-specific infection and transmission rates, indicating that outbreak isolates did not have a fitness advantage over COAV997-5nt. Collectively, WNV isolates from outbreaks demonstrated relatively greater avian, but not vector, replicative fitness compared to COAV997-5nt, similar to previously characterized non-outbreak isolates of WNV. Our results indicated that ecological rather than viral factors may facilitate WNV amplification to outbreak levels, but monitoring viral phenotypes through competitive fitness studies may provide insight into altered replication and transmission potential among emerging WNV strains. [ABSTRACT FROM AUTHOR]

Background: The media plays as an important role in delivering information about emergent issues, such as the Eastern equine encephalitis virus (EEEV) outbreak of 2019. As such, there has been an increase in news coverage of vector-borne disease coverage due to a rise in emerging or re-emerging arboviruses. Methods: The purpose of this study was to describe the content of news clips related to the recent (2019) EEEV outbreak in the United States. Results: Only 3 of the important topics identified were mentioned in a majority of the 110 videos analyzed. These topics were, mosquito mentioned as transmitter, prevention by repellent/ pesticide, and geography. Thus, many aspects of EEEV were lacking in coverage. Conclusion: A priority for public health professionals should be to engage in discourse with news media to assure that information disseminated via news channels is not vague or misleading. [ABSTRACT FROM AUTHOR]

Insecticide resistance is an increasing problem worldwide that limits the efficacy of control methods against several pests of health interest. Among them, Aedes albopictus mosquitoes are efficient vectors of relevant pathogens causing animal and human diseases worldwide, including yellow fever, chikungunya, dengue, and Zika. Different mechanisms are associated in conferring resistance to chemical insecticides. One of the most widespread and analysed mechanisms is the knockdown resistance (kdr) causing resistance to DDT and pyrethroids. The mechanism is associated with mutations in the voltage sensitive sodium channel, which is involved in beginning and propagation of action potentials in nervous cells. The mechanism was originally discovered in the housefly and then it was found in a large number of arthropods. In 2011, a kdr associated mutation was evidenced for the first time in A. albopictus and afterward several evidences were reported in the different areas of the world, including China, USA, Brazil, India, and Mediterranean Countries. This review aims to update and summarize current evidences on kdr in A. albopictus, in order to stimulate further researches to analyse in depth A. albopictus resistance status across the world, especially in countries where the presence of this vector is still an emerging issue. Such information is currently needed given the well-known vector role of A. albopictus in the transmission of severe infectious diseases. Furthermore, the widespread use of chemical insecticides for control strategies against A. albopictus progressively lead to pressure selection inducing the rise of insecticide resistance-related mutations in the species. Such event is especially evident in some countries as China, often related to a history of uncontrolled use of chemical insecticides. Thus, a careful picture on the diffusion of kdr mutations worldwide represents a milestone for the implementation of control plans and the triggering of novel research on alternative strategies for mosquito-borne infections. [ABSTRACT FROM AUTHOR]

Summary: The global invasion of West Nile virus, chikungunya virus and Zika virus in the past two decades suggests an increasing rate of mosquito‐borne virus (arbovirus) dispersal. Rift Valley fever virus (RVFV) is an arbovirus identified as a high‐consequence threat to the United States (USA) because of the severe economic and health consequences associated with disease. Numerous studies demonstrate that the USA is receptive to RVFV transmission based on the widespread presence of competent mosquito species and vertebrate species. In this study, the potential pathways and locations of RVFV entry into the USA were quantitatively estimated to support a priori surveillance and RVFV prevention strategies. International movement data, ecological data and epidemiological data were combined to estimate the number of RVFV‐infected mosquitoes entering the USA. Results suggest infected humans travelling by plane pose the highest risk of importing RVFV into the USA, followed by the unintentional transport of infected adult mosquitoes by ship and airplane. Furthermore, New York, New York, Washington DC, Atlanta, Georgia, and Houston, Texas, are implicated as the most likely regions of RVFV entry. Results are interpreted and discussed to support the prediction and mitigation of RVFV spread to the USA. [ABSTRACT FROM AUTHOR]

Abstract: New techniques for the genetic modification of organisms are creating new strategies for addressing persistent public health challenges. For example, the company Oxitec has conducted field trials internationally—and has attempted to conduct field trials in the United States—of a genetically modified mosquito that can be used to control dengue, Zika, and some other mosquito‐borne diseases. In 2016, a report commissioned by the National Academies of Sciences, Engineering, and Medicine discussed the potential benefits and risks of another strategy, using gene drives. Driving a desired genotype through a population of wild animals or insects could lead to irreversible genetic modification of an entire species. The NASEM report recommends community, stakeholder, and public engagement about potential uses of the technology, and it argues that the engagement should occur as research advances, well before gene drives are deployed. Yet what “engagement” means in practice is unclear. This article seeks clarity on this problem by offering a justification for community engagement and drawing out implications of this argument for the implementation and desired outcomes of community engagement.Community engagement is essential when it comes to research that would release genetically modified insects or animals into the environment. By contrast, obtaining informed consent from people who live near such a proposed field trial is neither necessary nor sufficient. Drawing on the epistemic and moral arguments for deliberative democracy, I propose two discrete mechanisms of community engagement: community advisory boards and deliberative forums, neither of which has been systematically incorporated into research governance. The proposed mechanisms would engender respect for persons who live near field trials, even when the results of deliberation override some individuals’ preferences. Community engagement foregrounds the community in our thinking about humans’ relationship to nature, and it implies that deciding to release genetically modified insects or animals into the wild ought to be a collective decision, not one made by product developers, policy‐makers, private companies, research funders, or scientists alone. [ABSTRACT FROM AUTHOR]

Background: Zika virus transmission dynamics in urban environments follow a complex spatiotemporal pattern that appears unpredictable and barely related to high mosquito density areas. In this context, human activity patterns likely have a major role in Zika transmission dynamics. This paper examines the effect of host variability in the amount of time spent outdoors on Zika epidemiology in an urban environment. Methodology/Principal findings: First, we performed a survey on time spent outdoors by residents of Miami-Dade County, Florida. Second, we analyzed both the survey and previously published national data on outdoors time in the U.S. to provide estimates of the distribution of the time spent outdoors. Third, we performed a computational modeling evaluation of Zika transmission dynamics, based on the time spent outdoors by each person. Our analysis reveals a strong heterogeneity of the host population in terms of time spent outdoors–data are well captured by skewed gamma distributions. Our model-based evaluation shows that in a heterogeneous population, Zika would cause a lower number of infections than in a more homogenous host population (up to 4-fold differences), but, at the same time, the epidemic would spread much faster. We estimated that in highly heterogeneous host populations the timing of the implementation of vector control measures is the major factor for limiting the number of Zika infections. Conclusions/Significance: Our findings highlight the need of considering host variability in exposure time for managing mosquito-borne infections and call for the revision of the triggers for vector control strategies, which should integrate mosquito density data and human outdoor activity patterns in specific areas. [ABSTRACT FROM AUTHOR]

Today, malaria prevention hinges upon two domestic interventions: insecticide-treated bed nets and indoor residual spraying. As mosquitoes grow resistant to these tools, however, novel approaches to vector control have become a priority area of malaria research and development. Spatial repellency, a volumetric mode of action that seeks to reduce disease transmission by creating an atmosphere inimical to mosquitoes, represents one way forward. Drawing from research that sought to develop new repellent chemicals in conversation with users from sub-Saharan Africa and the United States, we consider the implications of a non-insecticidal paradigm of vector control for how we understand the political ecology of malaria. [ABSTRACT FROM AUTHOR]

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]

The distribution of mosquitoes and associated vector diseases (e.g., West Nile, dengue, and Zika viruses) is likely to be a function of environmental conditions in the landscape. Urban environments are highly heterogeneous in the amount of vegetation, standing water, and concrete structures covering the land at a given time, each having the capacity to influence mosquito abundance and disease transmission. Previous research suggests that socioeconomic status is correlated with the ecology of the landscape, with lower-income neighborhoods generally having more concrete structures and standing water via residential abandonment, garbage dumps, and inadequate sewage. Whether these socioecological factors affect mosquito distributions across urban environments in the USA remains unclear. Here, we present a meta-analysis of 42 paired observations from 18 articles testing how socioeconomic status relates to the overall mosquito burden in urban landscapes in the USA. We also analyzed how socioecological covariates (e.g., abandoned buildings, vegetation, education, and garbage containers) varied across socioeconomic status in the same mosquito studies. The meta-analysis revealed that lower-income neighborhoods (regions with median household incomes

Study Objectives: To review the clinical and basic science literature regarding Zika viral illness and highlight relevant findings for obstetric anesthesiologists. This review provides a global review of Zika viral illness, transmission patterns, pathophysiology of disease, and anesthetic management of the parturient with Zika viral illness and associated comorbidities.Design: Systematic review.Setting: Large academic hospital.Subjects: None.Interventions: None.Measurements: None.Main Results: None.Conclusion: With the rapid spread of Zika virus and expected increase of spread in the summer of 2016, this review provides anesthesiologists with current recommendations, physiologic alterations, and anesthetic considerations in regard to the parturient with Zika viral illness and associated diseases. [ABSTRACT FROM AUTHOR]

Discovered in 1947 in a monkey in the Zika forest of Uganda, Zika virus was dismissed as a cause of a mild illness that was confined to Africa and Southeast Asia and transmitted by Aedes mosquitoes. In 2007, Zika virus appeared outside of its endemic borders in an outbreak on the South Pacific Island of Yap. In 2013, Zika virus was associated with a major neurological complication, Guillain-Barré syndrome, in a larger outbreak in the French Polynesian Islands. From the South Pacific, Zika invaded Brazil in 2015 and caused another severe neurological complication, fetal microcephaly. The mosquito-borne transmission of Zika virus can be propagated by sexual transmission and, possibly, by blood transfusions, close personal contacts, and organ transplants, like other flaviviruses. Since these combined mechanisms of infectious disease transmission could result in catastrophic incidences of severe neurological diseases in adults and children, the public should know what to expect from Zika virus, how to prevent infection, and what the most likely failures in preventive measures will be. With federal research funding stalled, a Zika vaccine is far away. The only national strategies to prepare the United States for Zika virus invasion now are effective vector control measures and personal protection from mosquito bites. In addition to a basic knowledge of Aedes mosquito vectors and their biting behaviors, an understanding of simple household vector control measures, and the selection of the best chemical and physical mosquito repellents will be required to repel the Zika threat. [ABSTRACT FROM AUTHOR]

Background: The massive pandemic of Zika virus (ZIKV) infection is spreading through South America, Central America, the Caribbean, and possibly the USA. It is the most recent of four surprising appearances of imperative arthropod-borne viral illnesses in the Western Hemisphere over the preceding 20 years. Objective: The objective of this narrative review is to summarize the existing knowledge about the epidemiology, transmission, clinical manifestations, complications, replication, pathogenesis, diagnosis, and treatment and prevention of ZIKV infection. Methods: We used electronic databases to identify relevant published data regarding ZIKV in BOOLEAN and MeSH searches. Conclusion: This review concludes that the ZIKV predominantly circulates in arboreal mosquitoes (e.g., Aedes africanus) and wild primates. It rarely causes severe infection in humans, even in extremely enzootic regions. Currently, we do not have any efficacious drugs against ZIKV infection. However, there are virus-specific therapeutic targets, which may lead to the development of targeted anti-ZIKV drugs. [ABSTRACT FROM AUTHOR]

The author discusses an article published in late 2017 by the "Lancet" medical journal which tracked 41 indicators of climate change and discusses the health implications of climate change, offering suggestions to reduce the cumulative risk and addressing the affects of climate change on U.S. public health and the economy.

Rift Valley fever (RVF) is a zoonotic disease endemic in sub-Saharan Africa with periodic outbreaks in human and animal populations. Mosquitoes are the primary disease vectors; however, Rift Valley fever virus (RVFV) can also spread by direct contact with infected tissues. The transmission cycle is complex, involving humans, livestock, and multiple species of mosquitoes. The epidemiology of RVFV in endemic areas is strongly affected by climatic conditions and environmental variables. In this research, we adapt and use a network-based modeling framework to simulate the transmission of RVFV among hypothetical cattle operations in Kansas, US. Our model considers geo-located livestock populations at the individual level while incorporating the role of mosquito populations and the environment at a coarse resolution. Extensive simulations show the flexibility of our modeling framework when applied to specific scenarios to quantitatively evaluate the efficacy of mosquito control and livestock movement regulations in reducing the extent and intensity of RVF outbreaks in the United States. [ABSTRACT FROM AUTHOR]

The article discusses efforts of U.S. public health agencies to prepare for the Zika virus epidemic, which began in Brazil in May 2015, as it enters the U.S. Topics include the detection of microcephaly in addition to other birth defects and Guillain-Barre syndrome as complications of Zika, transmission of the Zika virus to U.S. residents through mosquito bites during travel to affected countries or sex with an infected person, and mosquito abatement programs to contain transmission by mosquitoes in the U.S.