Evaluation of toxicity and environmental safety in use of spinosad to rationalize control strategies against Aedes aegypti

AbstractIdentifying Aedes aegypti breeding hotspots in urban areas is crucial for the design of effective vector control strategies. Remote sensing techniques offer valuable tools for mapping habitat suitability. In this study, we evaluated the association between urban landscape, thermal features, and mosquito infestations. Entomological surveys were conducted between 2016 and 2019 in Vila Toninho, a neighborhood of São José do Rio Preto, São Paulo, Brazil, in which the numbers of adult female Ae. aegypti were recorded monthly and grouped by season for three years. We used data from 2016 to 2018 to build the model and data from summer of 2019 to validate it. WorldView-3 satellite images were used to extract land cover classes, and land surface temperature data were obtained using the Landsat-8 Thermal Infrared Sensor (TIRS). A multilevel negative binomial model was fitted to the data, which showed that the winter season has the greatest influence on decreases in mosquito abundance. Green areas and pavements were negatively associated, and a higher cover of asbestos roofs and exposed soil was positively associated with the presence of adult females. These features are related to socio-economic factors but also provide favorable breeding conditions for mosquitos. The application of remote sensing technologies has significant potential for optimizing vector control strategies, future mosquito suppression, and outbreak prediction.

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The Global Expansion of Dengue: How Aedes aegypti Mosquitoes Enabled the First Pandemic Arbovirus

Annual Review of Entomology ◽

10.1146/annurev-ento-011019-024918 ◽

2020 ◽

Vol 65 (1) ◽

pp. 191-208 ◽

Cited By ~ 29

Author(s):

Oliver J. Brady ◽

Simon I. Hay

Keyword(s):

Invasive Species ◽

Aedes Aegypti ◽

Infectious Diseases ◽

Control Strategies ◽

Viral Disease ◽

Rapid Rise ◽

Disease Vector ◽

Research Priority ◽

Global Spread ◽

Human Habitation

Dengue is an emerging viral disease principally transmitted by the Aedes ( Stegomyia) aegypti mosquito. It is one of the fastest-growing global infectious diseases, with 100–400 million new infections a year, and is now entrenched in a growing number of tropical megacities. Behind this rapid rise is the simple adaptation of Ae. aegypti to a new entomological niche carved out by human habitation. This review describes the expansion of dengue and explores how key changes in the ecology of Ae. aegypti allowed it to become a successful invasive species and highly efficient disease vector. We argue that characterizing geographic heterogeneity in mosquito bionomics will be a key research priority that will enable us to better understand future dengue risk and design control strategies to reverse its global spread.

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Urban Landscape Features Influence the Movement and Distribution of the Australian Container-Inhabiting Mosquito Vectors Aedes aegypti (Diptera: Culicidae) and Aedes notoscriptus (Diptera: Culicidae)

Journal of Medical Entomology ◽

10.1093/jme/tjz187 ◽

2019 ◽

Cited By ~ 1

Author(s):

Brendan J Trewin ◽

Daniel E Pagendam ◽

Myron P Zalucki ◽

Jonathan M Darbro ◽

Gregor J Devine ◽

...

Keyword(s):

Aedes Aegypti ◽

Urban Landscape ◽

Mosquito Control ◽

Control Strategies ◽

Oviposition Behavior ◽

Gaussian Kernel ◽

Mosquito Vectors ◽

Landscape Features ◽

Rainwater Tanks

Abstract Urban landscape features play an important role in the distribution and population spread of mosquito vectors. Furthermore, current insecticide and novel rear-and-release strategies for urban mosquito management rarely consider the spatial structure of the landscape when applying control practices. Here, we undertake a mark-recapture experiment to examine how urban features influence the movement and distribution of Australian container-inhabiting Aedes vectors. We pay attention to the role of semipermanent water storage containers, called rainwater tanks, and the influence of movement barriers, such as roads, on the spread and distribution of vector populations. Results suggest that Aedes aegypti (Linnaeus) (Diptera: Culicidae) were more likely to be captured around rainwater tanks, and that released males travel throughout residential blocks but do not cross roads. Conversely, female Aedes notoscriptus (Skuse) (Diptera: Culicidae) movement was uninhibited by roads and rainwater tanks did not influence female distribution or oviposition behavior. Using an isotropic Gaussian kernel framework, we show that vector movement is likely to be greater when applying a temporal effect, than when estimated by traditional methods. We conclude that a greater understanding on the role of urban features on vector movement will be important in the new age of rear-and-release mosquito control strategies, particularly those where estimations of movement are important for ensuring efficacy of application.

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Selection of Aedes aegypti (Diptera: Culicidae) strains that are susceptible or refractory to Dengue-2 virus

The Canadian Entomologist ◽

10.4039/tce.2012.105 ◽

2013 ◽

Vol 145 (3) ◽

pp. 273-282 ◽

Cited By ~ 5

Author(s):

Paola A. Caicedo ◽

Olga L. Barón ◽

Mauricio Pérez ◽

Neal Alexander ◽

Carl Lowenberger ◽

...

Keyword(s):

Aedes Aegypti ◽

Molecular Mechanisms ◽

Selection Process ◽

Control Strategies ◽

Vector Competence ◽

Survival Rates ◽

Kaplan Meier ◽

Genetic And Environmental Factors ◽

Seven Generations ◽

Selection Of

AbstractThe vector competence (VC) of Aedes aegypti (Linnaeus) (Diptera: Culicidae) varies geographically and is affected by both genetic and environmental factors. Understanding the molecular mechanisms that influence VC may help develop novel control strategies. The selection of susceptible and refractory strains is the first step in this process. We collected immature A. aegypti in the field and established strains that were susceptible and refractory to Dengue-2 virus by isofamily selection through several generations. Infection was detected by immunofluorescence of head or midgut tissues to determine infection barriers and the % of VC by tissue. We selected three strains: Susceptible (Cali-S) (96.4% susceptible at F19), Refractory with a midgut escape barrier (Cali-MEB) (44.1% refractory at F15), and Refractory with a midgut infection barrier (Cali-MIB) (40% refractory at F16). The effects of the infection were measured using Kaplan–Meier survival rates over the first seven generations. All selected strains showed a similar decrease in survival and in the number of eggs laid/female through the seven generations, suggesting that changes were a result of the selection process rather than the virus infection. The results of this study suggest that VC is associated with multiple genes, which have additive effects on susceptibility.

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Systematic Review: The Impact of Socioeconomic Factors on Aedes aegypti Mosquito Distribution in the Mainland United States

10.20944/preprints201910.0190.v1 ◽

2019 ◽

Author(s):

Whitney Holeva-Eklund ◽

Timothy Behrens ◽

Crystal Hepp

Keyword(s):

United States ◽

Aedes Aegypti ◽

Socioeconomic Factors ◽

Control Strategies ◽

Anthropogenic Factors ◽

Eligibility Criteria ◽

Screening Process ◽

Close Relationship ◽

Meta Analyses ◽

The Impact

Background: Aedes aegypti mosquitoes are primary vectors of dengue, yellow fever, chikungunya and Zika viruses. A. aegypti is highly anthropophilic and relies nearly exclusively on human blood meals and habitats for reproduction. Socioeconomic factors may influence the spread of A. aegypti due to their close relationship with humans. This paper describes and summarizes the published literature on how socioeconomic variables influence the distribution of A. aegypti mosquitoes in the mainland United States. Methods: A comprehensive search of PubMed/Medline, Scopus, Web of Science, and EBSCO Academic Search Complete through June 12, 2019 was used to retrieve all articles published in English on the association of socioeconomic factors and the distribution of A. aegypti mosquitoes. Articles were screened for eligibility using the process described in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results: Initially, 3,493 articles were identified through the database searches and previously known literature. After checking for duplicates, 2,145 articles remained. These articles were screened for eligibility using their titles and abstracts, and 2,098 articles were excluded for not meeting the eligibility criteria. Finally, the full text for each of the remaining articles (n = 38) was read to determine eligibility. Through this screening process, 11 articles were identified for inclusion in this review. Conclusions: The findings for these 11 studies revealed inconsistent relationships between the studied socioeconomic factors and the distribution and abundance of A. aegypti. The findings of this review suggest a gap in the literature and understanding of the influence of anthropogenic factors on the distribution of A. aegypti that could hinder efforts to implement effective public health prevention and control strategies should a disease outbreak occur.

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Intracellular Interactions Between Arboviruses and Wolbachia in Aedes aegypti

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2021.690087 ◽

2021 ◽

Vol 11 ◽

Author(s):

Jerica Isabel L. Reyes ◽

Yasutsugu Suzuki ◽

Thaddeus Carvajal ◽

Maria Nilda M. Muñoz ◽

Kozo Watanabe

Keyword(s):

Aedes Aegypti ◽

Vector Control ◽

Host Species ◽

Control Strategies ◽

Cytoskeletal Proteins ◽

Cellular Interactions ◽

Cellular Mechanisms ◽

Cellular Regeneration ◽

Release Program ◽

Human Infections

Aedes aegypti is inherently susceptible to arboviruses. The geographical expansion of this vector host species has led to the persistence of Dengue, Zika, and Chikungunya human infections. These viruses take advantage of the mosquito’s cell to create an environment conducive for their growth. Arboviral infection triggers transcriptomic and protein dysregulation in Ae. aegypti and in effect, host antiviral mechanisms are compromised. Currently, there are no existing vaccines able to protect human hosts from these infections and thus, vector control strategies such as Wolbachia mass release program is regarded as a viable option. Considerable evidence demonstrates how the presence of Wolbachia interferes with arboviruses by decreasing host cytoskeletal proteins and lipids essential for arboviral infection. Also, Wolbachia strengthens host immunity, cellular regeneration and causes the expression of microRNAs which could potentially be involved in virus inhibition. However, variation in the magnitude of Wolbachia’s pathogen blocking effect that is not due to the endosymbiont’s density has been recently reported. Furthermore, the cellular mechanisms involved in this phenotype differs depending on Wolbachia strain and host species. This prompts the need to explore the cellular interactions between Ae. aegypti-arboviruses-Wolbachia and how different Wolbachia strains overall affect the mosquito’s cell. Understanding what happens at the cellular and molecular level will provide evidence on the sustainability of Wolbachia vector control.

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Intracellular Interactions between Arboviruses and Wolbachia in Aedes aegypti

10.20944/preprints202104.0151.v1 ◽

2021 ◽

Author(s):

Jerica Isabel Reyes ◽

Yasutsugu Suzuki ◽

Thaddeus Carvajal ◽

Maria Nilda Muñoz ◽

Kozo Watanabe

Keyword(s):

Aedes Aegypti ◽

Vector Control ◽

Control Strategies ◽

Host Responses ◽

Cellular Interactions ◽

Viral Inhibition ◽

Cellular Mechanisms ◽

Release Program ◽

Human Infections ◽

Cellular Components

Aedes aegypti is inherently susceptible to arboviruses. The geographical expansion of this vector host species has led to the persistence of Dengue, Zika and Chikungunya human infections. These viruses take advantage of the mosquito’s cell to create an environment conducive for their growth. Arboviral infection triggers transcriptomic and protein dysregulation in Ae. aegypti and in effect, host antiviral mechanisms are compromised. Currently, there are no existing vaccines able to protect human hosts from these infections and thus, vector control strategies such as Wolbachia mass release program is regarded as a viable option. Considerable evidence demonstrates how the presence of Wolbachia interferes with arboviruses by decreasing cellular components vital for the pathogen and strengthening antiviral host responses. However, variation in the magnitude of Wolbachia’s viral inhibition that is neither due to strain nor density has been observed. Furthermore, the cellular mechanisms involved in the endosymbiont’s pathogen-blocking differs among hosts. This prompts the need to explore the cellular interactions between Ae. aegypti-arboviruses-Wolbachia and how these interactions overall affect the mosquito’s cell. Understanding what happens at the cellular and molecular level will provide evidence on the sustainability of Wolbachia vector control.

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The Developmental Transcriptome of Ae. albopictus, a Major Worldwide Human Disease Vector

10.1101/753962 ◽

2019 ◽

Cited By ~ 2

Author(s):

Stephanie Gamez ◽

Igor Antoshechkin ◽

Stelia C. Mendez-Sanchez ◽

Omar S. Akbari

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Human Disease ◽

Control Strategies ◽

Expression Profiles ◽

Expression Patterns ◽

Significant Differential Expression ◽

Disease Vector ◽

Biological Studies ◽

Similarities And Differences

AbstractAedes albopictus mosquitoes are important vectors for a number of human pathogens including the Zika, dengue, and chikungunya viruses. Capable of displacing Aedes aegypti populations, it adapts to cooler environments which increases its geographical range and transmission potential. There are limited control strategies for Aedes albopictus mosquitoes which is likely attributed to the lack of comprehensive biological studies on this emerging vector. To fill this void, here using RNAseq we characterized Aedes albopictus mRNA expression profiles at 47 distinct time points throughout development providing the first high-resolution comprehensive view of the developmental transcriptome of this worldwide human disease vector. This enabled us to identify several patterns of shared gene expression among tissues as well as sex-specific expression patterns. Moreover, to illuminate the similarities and differences between Aedes aegypti, a related human disease vector, we performed a comparative analysis using the two developmental transcriptomes. We identify life stages were the two species exhibited significant differential expression among orthologs. These findings provide insights into the similarities and differences between Aedes albopictus and Aedes aegypti mosquito biology. In summary, the results generated from this study should form the basis for future investigations on the biology of Aedes albopictus mosquitoes and provide a goldmine resource for the development of transgene-based vector control strategies.

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The juvenile hormone receptor Methoprene-tolerant is involved in the sterilizing effect of pyriproxyfen on adult Aedes aegypti mosquitoes

10.1101/2020.05.31.126508 ◽

2020 ◽

Author(s):

Tahmina Hossain Ahmed ◽

T. Randolph Saunders ◽

Donald Mullins ◽

Mohammad Zillur Rahman ◽

Jinsong Zhu

Keyword(s):

Aedes Aegypti ◽

Juvenile Hormone ◽

Mosquito Control ◽

Fat Body ◽

Control Strategies ◽

Follicular Development ◽

Blood Feeding ◽

Oocyte Development ◽

Hormonal Responses ◽

Before And After

AbstractExposure of adult mosquitoes to pyriproxyfen (PPF), an analog of insect juvenile hormone (JH), has shown promise to effectively sterilize female mosquitoes. However, the underlying mechanisms of the PPF-induced decrease in mosquito fecundity are largely unknown. We performed a comprehensive study to dissect the mode of PPF action in Aedes aegypti mosquitoes. Exposure to PPF prompted the overgrowth of primary follicles in sugar-fed Ae. aegypti females but blocked the development of primary follicles at Christopher’s Stage III after blood feeding. Secondary follicles were precociously activated in PPF-treated mosquitoes. Moreover, PPF substantially altered the expression of many genes that are essential for mosquito physiology and oocyte development in the fat body and ovary. In particular, many metabolic genes were differentially expressed in response to PPF treatment, thereby affecting the mobilization and utilization of energy reserves. Furthermore, PPF treatment on the previtellogenic female adults considerably modified mosquito responses to JH and 20-hydroxyecdysone (20E), two major hormones that govern mosquito reproduction. Krüppel homolog 1, a JH-inducible transcriptional regulator, showed consistently elevated expression after PPF exposure. Conversely, PPF upregulated the expression of several key players of the 20E regulatory cascades, including HR3 and E75A, in the previtellogenic stage. After blood-feeding, the expression of these 20E response genes was significantly weaker in PPF-treated mosquitoes than the solvent-treated control groups. RNAi-mediated knockdown of the Methoprene-tolerant (Met) protein, the JH receptor, partially rescued the impaired follicular development after PPF exposure and substantially increased the hatching of the eggs produced by PPF-treated female mosquitoes. Thus, the results suggested that PPF relied on Met to exert its sterilizing effects on female mosquitoes. In summary, this study finds that PPF exposure disturbs normal hormonal responses and metabolism in Ae. aegypti, shedding light on the molecular targets and the downstream signaling pathways activated by PPF.Author summaryAedes aegypti mosquitoes are responsible for the transmission of dengue, yellow fever, chikungunya, and Zika fever. Insecticides are widely used as the primary tool in the prevention and control of these infectious diseases. In light of the rapid increase of insecticide resistance in mosquito populations, there is an urgent need to find new classes of insecticides with a different mode of action. Here we found that pyriproxyfen, an analog of insect juvenile hormone (JH), had a large impact on the oocyte development, both before and after blood feeding, in female mosquitoes. Pyriproxyfen disturbed normal hormonal responses and caused metabolic shifting in female adults. These actions appear to collectively impair oocyte development and substantially reduce viable progenies of female mosquitoes. Besides, we demonstrated the involvement of the JH receptor Met in pyriproxyfen-induced female sterilization. This study significantly advances our understanding of mosquito reproductive biology and the molecular basis of pyriproxyfen action, which are invaluable for the development of new mosquito control strategies.

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Epidemiological profile of diseases caused by aedes aegypti in sanitary districts of São Luis, Brazil

European Journal of Public Health ◽

10.1093/eurpub/ckaa166.141 ◽

2020 ◽

Vol 30 (Supplement_5) ◽

Author(s):

ECR Dos Santos ◽

S C Cohren ◽

R G R Costa

Keyword(s):

Aedes Aegypti ◽

Zika Virus ◽

Control Strategies ◽

Public Health Problem ◽

Female Gender ◽

The State ◽

Impact Of Urbanization ◽

Epidemiological Profile ◽

The Impact ◽

Sanitary District

Abstract In recent decades, the diseases caused by the Aedes aegypti have been responsible for a high number of mortality cases worldwide, making it a serious public health problem. This article describes the diseases prevalence caused by Aedes Aegypti: Dengue, Zika and Chikungunya, in the Sanitary Districts of city of São Luis - in the state of Maranhão in Brazil, from 2007 to 2017. This study is based on data analysis recorded by the Information System on Diseases of Compulsory Declaration (SINAN). From 2007 to 2017, 25,124 dengue cases were reported in the city of São Luís, there was an increase in prevalence in 2011 with 5,378 cases, about 53% of recorded cases in the State of Maranhão, probably due to the presence of new circulating serotypes: DENV-1; DENV-2 AND DENV-4, with 14 deaths. Female gender predominated among registered cases, and the age group with the highest number of reported cases was 20 to 39 years. In 2015 started the first reports of the Zika virus and chikungunya, both with epidemiological peak in 2016. São Luis has 229 urban neighborhoods and 165 rural neighborhoods distributed in seven health districts. The Bequimão Sanitary District in the urban area of city of São Luis consists of 64 neighborhoods, has recorded a higher number of dengue cases, 6,239 cases. From 2015 to 2017, it reported 864 cases of Zika virus and 407 cases of chikungunya. It is concluded that the prevalence of diseases, caused by Aedes aegypti, shows endemic variation, in the three arboviruses, related to population density and local sanitary conditions, characteristics which are present in the Sanitary District of Bequimão where it's registered a lack of sanitary infrastructure and intermittent water supply, the study notes the need to adopt control strategies of sanitary officers, and agencies and awareness of the population. Key messages The research produced knowledge about the impact of urbanization on the epidemiology of dengue, zika and chikungunya, enabling knowledge of the sanitation conditions of the studied city. The knowledge produced by the research substantiates strategies and actions to combat the vector by the health authorities and conscious action of the population.

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