Mosquitoes pose a serious threat to the economy, health status, and biosecurity of countries around the world. Mosquitoes kill an average of 700,000 people per year. The global expansion of air, sea, and land transport networks has greatly enhanced the spread of mosquitoes internationally. In the Pacific, the number of mosquito-borne diseases occurring has been on the rise in recent years, possibly as a result of human-mediated dispersal of larvae and adult mosquitoes. The Kingdom of Tonga has had numerous outbreaks of dengue fever and chikungunya virus in recent years. Previous research has catalogued species occurrences and distributions throughout Tonga. However, it is unknown whether new species have arrived in Tonga, and if distribution of previously found species has changed since the last comprehensive survey in 2006. Present research aims to update the literature by conducting a mosquito survey at 84 sites across the four islands of Tongatapu, Pangaimotu, ‘Oneata, and ‘Eua to record the distribution and occurrence of mosquito larvae. Nine mosquito species were collected: Aedes aegypti Linnaeus, A. albopictus Skuse, A. tongae Edwards, A. horrescens Edwards, A. vexans nocturnus Theobold, Culex annulirostris Skuse, C. albinervis Edwards, C. quinquefasciatus Say and C. sitiens Wiedemann. The collection of A. albopictus is the second time that this species has been recorded in Tonga. Moreover, the spatial extent of this species throughout Tonga was far greater than previously recorded. A major outcome of this survey has been the creation of an identification key for the mosquito larvae species of Tonga. This key should increase the accuracy of positive mosquito larvae identifications in Tonga. Mosquitoes were more frequently collected in artificial (e.g., used car tyres, fuel drums, containers) than natural (e.g., pools, ponds, tree holes) habitats. Car tyres, water containers, fuel drums, fridges, washing machines, and ponds were the most common habitats in which mosquito larvae were found. Aedes aegypti, A. albopictus, and C. quinquefasciatus were the three most common mosquito species collected, whereas A. tongae, A. horrescens, A. vexans nocturnus, C. annulirostris, C. sitiens, and C. albinervis were less frequently found. Multiple logistic regression analyses indicated that habitat volume had a significant positive effect on the presence of A. albopictus and A. tongae, whereas conductivity had a significant positive effect on the presence of C. annulirostris. Additionally, the volume by temperature interaction was a significant predictor of species presence for A. aegypti, A. albopictus, and C. annulirostris (as habitat volume increases, the effect of temperature went from neutral to negative). This suggests that larger, cooler habitats favour colonisation by these species. The number of artificial habitats (particularly used car tyres) present may have significantly increased since previous studies. Management should therefore focus on implementing community-run mosquito projects aimed at reducing the number of artificial habitats capable of being colonised by mosquito larvae. Covering, tipping out water, and infilling these habitats with soil to prevent mosquito oviposition is a pragmatic and straightforward mosquito control solution. This should immensely reduce the abundance of mosquitoes and may prevent disease outbreak in Tonga.

Introducción: El Dengue es una enfermedad infecciosa, que constituye un problema de salud pública a nivel nacional e internacional, por el incremento del número de casos y que aumentan los casos de morbi-mortalidad en las personas. Objetivo:Determinar el efecto de una intervención educativa en enfermería en el incremento del nivel de conocimientos y mejora de prácticas preventivas contra el Dengue en los pobladores adultos de la Asociación Los Claveles – Lurín 2015. Metodología: Estudio de enfoque cuantitativo, tipo aplicativo, de método experimental y de diseño pre – experimental, con una muestra de 30 pobladores adultos de la Asociación “Los Claveles – Lurín”, de selección muestral no probabilístico por conveniencia; la técnica que se utilizó para obtener la recolección de datos fue la encuesta y la guía de observación, como instrumento se utilizó dos cuestionarios estructurados sobre conocimientos y prácticas preventivas con preguntas de opción múltiple; en la intervención educativa se aplicó primero el pre-test, seguido por 2 sesiones educativas y por talleres demostrativos sobre el lavado, tapado hermético de los envases de agua y la conservación de floreros, y posterior a ello se aplicó el post-test; y por último se utilizó una guía de observación para las prácticas preventivas. Para el análisis de datos se utilizó el programa SPSS versión 21. Resultados: El nivel de conocimiento antes de la intervención educativa fue un nivel medio 77% (23) y después de la intervención educativa fue de alto el 90% (27) y 10% (3) nivel medio dado el valor de T de Student -12,1791 (P=0,00000); y las prácticas preventivas antes de la intervención educativa eran inadecuadas 57% (17) y despúes adecuadas 80% (24) e inadecuadas 20% (6) con un valor de T de Student de -11,9721 (P=0,00000).Conclusión:La aplicación de la intervención educativa tuvo un efecto significativo en el incremento de conocimiento y prácticas preventivas contra el Dengue en los pobladores.

Compreender a fisiologia reprodutiva de Aedes aegypti, vetor primário do vírus dengue, é uma etapa básica para o desenvolvimento de novos métodos de controle. Baseado nesta premissa, estudos de expressão gênica durante o ciclo gonotrófico de Aedes aegypti foram realizados neste trabalho e foram identificados 3 genes com expressão elevada nos ovários na fase de término do período vitelogênico, 48 horas após o repasto. Interessantemente, foi mostrado que o gene AAEL01714, anotado in silico como codificante para uma proteína ligadora de odor atípica OBP45 (ZHOU et al., 2008), é transcrito nas células foliculares que envolvem os oócitos. A caracterização da sequência completa do cDNA de AAEL010714 levou a identificação de uma fase aberta de leitura (ORF) codificante para uma proteína putativa, que foi nomeada como OBP45B atípica. Experimentos de Western blot evidenciaram que esta proteína é sintetizada nos ovários. Este estudo descreve a primeira caracterização molecular de um gene de Aedes aegypti que codifica para uma OBP atípica, expressa em ovários. / Understanding the reproductive physiology of Aedes aegypti, the primary vector of dengue virus, is a basic step to develop new control methods. Based on this premise, studies on gene expression during Aedes aegypti gonotrophic cycle were performed and we found 3 genes with high expression in ovaries at the end phase of the vitellogenic period, 48 hours after blood meal. Interestingly, it was shown that the gene AAEL01714, in silico annotated as encoding for atypical odorant binding protein OBP45 (ZHOU et al., 2008), is transcribed in the follicle cells surrounding the oocyte. Characterization of AAEL010714 full length cDNA led us to identify an open reading frame (ORF) which encodes for a protein named as atypical OBP45B. Western blot experiments showed that this protein is synthesized in the ovaries. This study describes the first molecular characterization of an Aedes aegypti gene encoding for an atypical OBP that is expressed in ovaries.

Made available in DSpace on 2015-04-22T22:06:15Z (GMT). No. of bitstreams: 1 Ivana Cristina Lopes da Cunha.pdf: 2287821 bytes, checksum: b8be5da98e942cd7c40cc08eb0d09841 (MD5) Previous issue date: 2009-05-27 / The most important vector of Dengue virus is Aedes aegypti, an originally African mosquito species. The presence of this vector in the Americas dates back to the 17th-18th centuries; it is thought to have been first introduced into Brazil by the beginning of the 20th century. However, the process of invasion of the continent by Ae. aegypti remains poorly understood, and the relationships between the dynamics of vector introduction/establishment/expansion and dengue epidemiological trends have not been thoroughly assessed. Here we test a series of hypotheses regarding the origins, number, and spatial and temporal dynamics of the invasion of the Americas by Ae. aegypti. Key predictions were tested using a database composed of over 3000 mitochondrial ND4 gene sequences. This database, which was compiled and completed in the course of the project, contains sequences from specimens collected in five regions of the Americas (from the United States to southern Brazil), in Africa, and in Asia. Analyses covered the following subjects: (i) genetic diversity; (ii) spatial patterns of haplotype occurrence; (iii) genealogical and phylogenetic relationships; (iv) population genetic structuring; and (v) historical demography. Results suggest two major, probably old events of Ae. aegypti introduction into the Americas. Both involved the early arrival of moderately divergent African populations to the Caribbean and North-Mesoamerica. One of these lineages dispersed to Venezuela and spread southwards in two invasion waves. The first wave reached northern Amazonia, where some sub-populations became isolated; we suggest that the spread of these vectors was involved in the first American dengue pandemic (1824-1828). The second, much more recent wave resulted in the colonization of most of South America by this lineage. In contrast, the second major lineage reached South America by the Brazilian Southeastern region, and dispersed northwards during the second pandemic (1845-1851); the persistence of this lineage in Brazil suggests that xi eradication campaigns were never completely successful. The secondary encounter of the descendants of both major lineages gave rise to the often-reported pattern of high genetic diversity. The data suggest that passive vector dispersal and the effects of control interventions on local populations produce a pattern of strong genetic structuring. The recent evolution of dengue epidemiological patterns in Brazil suggests that health sector reform and decentralization in the 1990s limited the efficacy of control interventions. We finally suggest how the results of studies on vector genetics can be incorporated into the design of better control-surveillance strategies; they can help identify more invasive or more diverse vector populations, or help define critical locations for entomological surveillance and control. Our data show how these interventions should be pursued even in localities already infested by the vector. We have developed, making use of data on population genetic variability, a comprehensive proposal on the process of invasion of the Americas by Ae. aegypti, and tentatively established the correspondence between the patterns of genetic diversity of this vector species and the spatial and temporal dynamics of dengue epidemiology in Brazil / O principal vetor do vírus Dengue é o Aedes aegypti, uma espécie originária da África. A presença do vetor nas Américas data dos séculos XVII-XVIII; a primeira introdução no Brasil aconteceu, provavelmente, no início do século XIX. Contudo, o processo de invasão do continente por Ae. aegypti ainda é mal compreendido, e as relações entre as dinâmicas de introdução/estabelecimento/expansão do vetor e as tendências epidemiológicas da doença não têm sido avaliadas de forma detalhada. Neste trabalho testamos uma série de hipóteses sobre as origens, número e dinâmicas espaciais e temporais da invasão das Américas por Ae. aegypti. As predições-chave foram testadas utilizando uma base de mais de 3000 seqüências de um fragmento do gene ND4 mitocondrial. Esta base, compilada e completada durante o desenvolvimento deste projeto, contém dados de espécimes de cinco regiões das Américas (desde os Estados Unidos até o Sul do Brasil), da África e da Ásia. As análises incluíram os seguintes aspectos: (i) diversidade genética; (ii) padrões espaciais de ocorrência de diferentes haplótipos; (iii) relações genealógicas e filogenéticas; (iv) estruturação genética populacional; e (v) demografia histórica. Os resultados sugerem dois eventos principais, provavelmente antigos, de introdução de Ae. aegypti nas Américas. Ambos envolveram a chegada inicial de populações africanas moderadamente diferenciadas à região do Caribe/Norte-Mesoamérica. Uma destas linhagens se dispersou até a Venezuela e avançou para o sul em duas ondas. A primeira onda alcançou o norte da Amazônia, onde algumas sub-populações ficaram isoladas; sugerimos que a dispersão destes vetores foi a responsável pela primeira pandemia americana de dengue (1824-1828). A segunda onda, muito mais recente, resultou na colonização de grande parte da América do Sul. A segunda linhagem, pelo contrário, alcançou o continente Sul-americano pelo Sudeste do Brasil, e se dispersou em direção norte durante a segunda pandemia (1845- ix 1851); a persistência desta linhagem no país sugere que as campanhas de erradicação nunca alcançaram seu objetivo. O encontro secundário dos descendentes das duas linhagens principais é responsável pelo padrão repetidamente reportado de alta diversidade genética das populações locais. Os dados sugerem que a dispersão passiva do vetor e os efeitos das ações de controle geram um padrão de forte estruturação genética. Em conjunto, os dados genéticos e a evolução recente do perfil epidemiológico da dengue no Brasil indicam que a efetividade das intervenções de controle se viu comprometida pelo processo de descentralização do sistema de saúde nos anos 1990. Finalmente, mostramos como os resultados das análises genéticas podem ajudar no desenho de melhores estratégias de controle e vigilância; eles podem ajudar a identificar sub-populações mais invasivas ou mais diversas do vetor, ou a definir pontos críticos para o controle-vigilância entomológicos. Os dados sugerem que estas intervenções serão importantes inclusive em localidades já colonizadas pelo vetor. Em definitiva, temos desenvolvido, utilizando dados sobre variabilidade genética populacional, uma proposta capaz de dar conta do processo de invasão das Américas por A. aegypti e estabelecido as possíveis correspondências entre os padrões de diversidade genética desta espécie de vetor e as dinâmicas espaciais e temporais da epidemiologia da dengue no Brasil.

This study investigated some functional and biochemical characteristics of a bacteriolytic protein in the salivary glands of adult Aedes aecupti. A method for the isolation of this protein from other mosquito salivary gland components is also described. Based on some of its biochemical properties, this bacteriolytic protein can be classified as a lysozyme. This protein is strongly-linked to mosquito sugarfeeding activity because there is a statistically significant (P < 0.05) increase in the levels of lytic activity six hours before mosquitoes start to sugar feed. By its bacteriolytic action, it may function as a protective mechanism against bacteria-contaminated sugar meals. Preliminary work suggests that mosquitoes exposed to lyophilized Micrococcus lysodeikticus in their sugar meal respond by increasing the lytic activity in their salivary glands. The levels of bacteriolytic activity are apparently not affected by bloodfeeding. In the absence of feeding, as in teneral and bloodfed mosquitoes, salivary bacteriolytic activity increases to a maximum, then levels off. This suggests a regulation of the synthesis of this salivary protein that is independent of the feeding state of the adult mosquito. A combination of centrifugation, polyacrylamide gel electrophoresis (non-denaturing and denaturing), cation exchange chromatography and gel filtration, was used to isolate the protein from other mosquito salivary gland components. This salivary protein is lysozyme-like in several aspects: 1) it lyses bacterial cell walls of M. lysodeikticus, 2) it is a basic protein with a pI between 7.47 and 8.89, 3) it is thermostable at low pH, and loses its activity at high pH, and 4) it is composed of one polypeptide chain. Its molecular weight is twice that of hen egg white lysozyme. This salivary bacteriolytic protein is the first insect exocrine lysozyme to be characterized. / Graduation date: 1992

Low level and variable transgene expression plague efforts to produce and characterize transgenic lines in many species. When transformation efficiency is high, productive transgenic lines can be generated with reasonable effort. However, most efforts to date in mosquitoes have resulted in suboptimal levels of transformation. This, coupled with the large space and intensive labor requirements of mosquito colony maintenance makes the optimization of transformation in mosquitoes a research priority. This study proposes two strategies for improving transgene expression and transformation efficiency. The first is to explore exogenous promoter/enhancer combinations to direct expression of either the transgene itself, or the transposase required for insertion of the transgene into the genome. An extension of this strategy is to investigate the use of a powerful viral transactivating protein and its cognate enhancer to further increase expression of these targets. The second strategy involves the identification of an endogenous boundary element for use in insulating transgenes and their associated regulatory elements. This would mitigate the inappropriate expression or silencing of many transgenes inserted into “unfavorable” genomic environments as a consequence of an inability to specifically target the integration of transposons currently used in mosquito transgenesis. The IE1 transactivating protein and its cognate enhancer from a baculovirus were shown to significantly increase expression of a reporter gene from three different promoters in cultured mosquito cells. Other heterologous enhancer/promoter combinations resulted in minimal increases or insignificant changes in expression. Orthologues of the vertebrate insulator-binding factor, CTCF, were cloned and characterized in two mosquito species, Aedes aegypti and Anopheles gambiae. The expression profile of mosquito CTCF is consistent with its role as a putative insulatorbinding protein. Preliminary binding site studies reveal a C/G-rich binding site consistent with that known in vertebrates and indicate that CTCF may bind widespread sites within mosquito genomes.

Abstract Background. Vector borne diseases such as dengue fever and malaria are spread through hematophagous insects. Aedes aegypti is a species of mosquito that transmits dengue and chikungunya in Asia. In Lao PDR the estimated direct and indirect cost of dengue fever alone is 5 million USD. Even though research and innovations in the field of vaccines are moving forward there are yet no effective treatments for these diseases. Vector control methods are in place to suppress the Ae. aegypti population but there are still more than 100,000 cases annually. However, insecticide resistance, mosquito behavioral changes, high costs and health issues make todays measures inadequate. An effective measure is to decrease the mosquito-human contact by applying topical repellents. Aims. This study investigates plants used traditionally for repelling hematophagous insects in Laos, with the aim of finding means to empower local communities to create their own repellents. Methods. After interviewing local communities in Laos and reviewing literature, 24 candidate species were compiled. Lemongrass (Cymbopogon citratus) and ginger (Zingiber officinale) were hydro-distilled to extract essential oils. These oils were then analyzed through GS-MS to understand their chemical composition. Finally the essential oils were formulated with soybean oil to pilot a topical repellent that was tested in vivo on Ae. aegypti under controlled conditions. Results. The formulations elicited about 60 minutes of full protection but when combined, a possible additive effect was noted, prolonging the efficacy by nearly 50%. The main constituents of C. citratus are neral (34.77%) and geranial (56.44%) while, in the more complex, Z. officinale the main components are β-Linalool (9.84%), Geranial (14.44%) and Zingiberene (14.43%). Discussion and conclusions. Botanical repellents are a viable, cheap and sustainable solution of repelling hematophagous disease vectors. The mixture of ginger and lemongrass oil can be further improved in formulation by stabilizing it, and thus prolonging the protection. Increasing yield using alternative means of extracting the essential oils would also make these oils more feasible for commercial production.

Thesis (M.Sc. (Tropical Medicine))--Mahidol University, 2003.

Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Includes bibliographical references (leaves 141-160). Issued in print and online. Available via ProQuest Digital Dissertations.

Orientador : Prof. Dr. Mário Antônio Navarro da Silva / Coorientadoras : Profª. Drª Adriana Lacerda Twerdochilib / Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Biológicas, Programa de Pós-Graduação em Ciências Biológicas (Entomologia). Defesa: Curitiba, 29/06/2015 / Referências: f. 51-59 / Resumo: O Aedes (Stegomyia) albopictus (Skuse 1894), conhecido como tigre asiático é considerado uma espécie invasora em diferentes países, no Brasil foi detectada pela primeira vez em 1986 e hoje está presente em grande parte do território nacional apresentando relevância epidemiológica devido à sua capacidade de colonizar ambientes silvestres e antrópicos associado ao seu elevado potencial vetorial para transmissão de diferentes arboviroses. Diante da relevância da espécie é de sua ampla distribuição o objetivo do estudo foi avaliar a diversidade genética de A. albopictus, utilizando duas ferramentas: morfometria geométrica alar e utilização do DNA mitocondrial. Foram estudadas populações provenientes de cinco municípios: Cianorte (PR), Foz do Iguaçu (PR), Maringá (PR), Rondonópolis (MT) e Porto Velho (RO). Foram utilizados 149 exemplares de mosquitos, sendo 11 de Rondonópolis, 42 de Maringá, 23 de Foz do Iguaçu, 19 de Cianorte e 54 de Porto Velhos os quais tiveram suas asas fotografadas e delimitadas 23 marcos anatômicos. Nas analises moleculares foi utilizado o gene mitocondrial ND5. Dos cinquenta indivíduos sequenciados, foram encontrados seis haplótipos, onde cinco foram detectados na área urbana de Maringá, dois em Foz do Iguaçu e nas demais localidades apenas com um haplótipo, as populações de Cianorte, Rondonópolis e Porto Velho, apresentaram o mesmo haplótipo. Foi detectada baixa variabilidade genética entre as populações e alta variabilidade intrapopulacional. Com auxílio da morfometria geométrica foi possível discriminar as populações de A. albopictus. / Abstract: The Aedes (Stegomyia) albopictus (Skuse 1894) - also known as Asiatic tiger - is considered an invasive species in different countries. It was detected in Brazil for the first time in 1986 and today it is present in a large part of the national territory, presenting epidemiologic relevance due to its ability to colonize wild and man-made environments associated to its high potential vector to the transmission of different arboviruses. Facing the relevance of the species and its wide distribution, the intention of this review was to evaluate A. albopictus' genetic diversity, using two ways: the geometric morphometric of the wing and utilization of mitochondrial DNA. The population from five cities have been studied: Cianorte (PR), Foz do Iguaçu (PR), Maringá (PR), Rondonópolis (MT) and Porto Velho (RO). Have been used 149 samples of mosquitoes, which 11 were from Rondonópolis, 42 from Maringá, 23 from Foz do Iguaçu, 19 from Cianorte and 54 from Porto Velho that have had their wings photographed and 23 anatomic marks delimitated. In the molecular analysis, the gene ND5 was used. From the 50 individuals sequenced, 6 haplotypes have been found, which 5 were detected in the urban area of Maringá, 2 in Foz do Iguaçu and just one in the other locations. The populations of Cianorte, Rondonópolis and Porto Velho presented the same haplotype. Low genetic variability and high intrapopulation variability was found. With the aid of geometric morphometry was possible to discriminate A. albopictus population.