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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Inquéritos soroepidemiológicos em eqüinos da região Sul do Brasil para detecção de anticorpos anti-flavivírus de interesse em saúde pública / Seroepidemiologic study in horses from southern Brazil to the detection of anti-flavivirus interest in public health

VIANNA, Ricardo da Silva Teixeira 02 July 2010 (has links)
Made available in DSpace on 2014-07-29T15:07:28Z (GMT). No. of bitstreams: 1 dissertacao FINAL RICARDO.pdf: 485243 bytes, checksum: 1906f1911ad5edaec8d73c8546aaca3e (MD5) Previous issue date: 2010-07-02 / The arboviruses are diseases that affect humans, horses and other animal species causing in the majority of cases an asymptomatic infection to neurological disorders. The Flaviviruses are important arbovirus found in Brazil. A descriptive study was conducted from serological surveys in 1775 horses for detection of anti-Flavivirus antibodies in the State of Paraná (Foz do Iguaçú, Maringá and Barracão), Santa Catarina (São Miguel do Oeste, Guaraciaba, Iraceminha, Dionisio Cerqueira, Guarujá do Sul and São José do Cedro) and Rio Grande do Sul (Uruguaiana, São Borja, Itaqui Alegrete and Porto Alegre) in the years of 2007 and 2008. By testing hemagglutination inhibition (HI) were detected HI antibodies of Saint Louis and Ilhéus and other Flaviviruses included in the tests, as well as cross-reactivity for Flaviviruses. By HI test, 14.3% (254/1775) of animals were positive for Flavivirus, monospecific reactions were observed in 42.9% (109/254) serum samples, being that 78.9% (86/109) for St. Louis, 17.4% (19/109) for Ilhéus and 3.7% (4 / 109) for Rocio and cross-reactions were detected in 57.1% (145/254). Among the positives, there was no difference between the sexes. The age group ≥ 10 years old was the most affected with 35.4% (73/206). The animals used for the practice of sport were positive in 34.3% (87/254). The state of Paraná showed 16.3% (107/657) of reacting animals, followed by Rio Grande do Sul with 15.1% (142/939) and Santa Catarina with 2.8% (5/179). This study brings new data regarding the immunity of horses against Flaviviruses in Brazil, and confirms the wide distribution of St. Louis and Ilhéus and the diversity of Flavivirus in the country, as well as the apparent absence of clinical disease in horses infected with the virus studied. / As arboviroses são enfermidades que acometem o homem, equinos e outras espécies animais causando na sua maioria das vezes infecções que vão desde assintomáticas até neurológicas. Os Flavivirus são importantes arbovírus encontrados no Brasil. Foi realizado um estudo descritivo a partir de inquéritos sorológicos em 1775 equinos para detecção de anticorpos anti-Flavivirus no Estado do Paraná (Foz do Iguaçu, Maringá e Barracão), Santa Catarina (São Miguel do Oeste, Guaraciaba, Iraceminha, Dionísio Cerqueira, Guarujá do Sul e São Jose do Cedro) e Rio Grande do Sul (Uruguaiana, São Borja, Itaqui, Alegrete e Porto Alegre) nos anos de 2007 e 2008. Por meio de testes de inibição da hemaglutinação (IH) foram detectados anticorpos IH de Saint Louis e Ilhéus e outros Flavivirus incluídos nos testes, assim como reações cruzadas para Flavivirus. Pelo teste de IH, 14,3% (254/1775) dos animais foram reagentes para Flavivirus, reações monoespecíficas foram observadas em 42,9% (109/254) amostras de soro, sendo que 78,9% (86/109) para Saint Louis, 17,4% (19/109) para Ilhéus e 3,7% (4/109) para Rocio e reações cruzadas foram detectadas em 57,1% (145/254). Dentre os animais reagentes, não foi observada diferença entre os sexos. A faixa etária ≥ 10 anos foi a mais acometida com 35,4% (73/206). Os animais utilizados para a prática do esporte foram reagentes em 34,3% (87/254). O Paraná apresentou 16,3% (107/657) dos animais reagentes, seguido do Rio Grande do Sul com 15,1% (142/939) e Santa Catarina com 2,8% (5/179). Este estudo traz novos dados a respeito da imunidade de equinos contra Flavivirus no Brasil, e confirma a ampla distribuição de Saint Louis e Ilhéus e a diversidade de Flavivirus no País, bem como a aparente ausência de doenças em equinos infectados pelos vírus estudados.
102

Atténuation virale par ré-encodage des codons : applications aux virus Chikungunya et de l'encéphalite à tiques / Viral attenuation by codon re-encoding : application to chikungunya and tick-borne encephalitis viruses

Fabritus, Lauriane de 14 April 2015 (has links)
Le ré-encodage aléatoire des codons à grande échelle est une nouvelle méthode d'atténuation virale qui consiste en l'insertion d'un grand nombre de mutations synonymes, individuellement peu délétères, de façon aléatoire dans une ou plusieurs régions codantes d'un virus. Cette approche permet de diminuer de façon significative et modulable le fitness réplicatif des virus in cellulo et in vivo, ainsi que la pathogénicité du virus chez la souris, tout en induisant une protection immunitaire spécifique et efficace lors d'une nouvelle infection par le virus sauvage. Les virus ré-encodés présentent également une grande stabilité et une absence de réversion ce qui en font des candidats vaccins très prometteurs en termes d'efficacité et de fiabilité pour la conception de candidats vaccins vivants atténués contre une grande variété de virus à ARN. La combinaison du ré-encodage aléatoire et d'une nouvelle méthode de génétique inverse permettant de générer de nouveaux virus en quelques jours: ISA (Amplicon Subgenomique Infectieux), est une approche prometteuse qui pourrait aider au développement de vaccins vivants atténués de nouvelle génération en un temps record. / Large-scale random codon re-encoding is a new method of viral attenuation consisting in the insertion of a high number of slightly deleterious synonymous mutations, randomly, in one or several coding regions of a virus. This approach significantly reduces the replicative fitness of re-encoded viruses in cellulo and in vivo, as viral pathogenicity, while inducing a specific and effective immune response in mice against a new infection with wild-type viruses. Re-encoded viruses also present a high stability and an absence of reversion, making them promising vaccine candidates in term of reliability and efficiency for the conception of new vaccine candidates against a wide variety of RNA viruses. Combination of random re-encoding with a new method of revers genetics allowing to generate new viruses in days : ISA (Infectious Subgenomic Amplicons) would be very helpful to develop new-generation vaccine candidates.
103

Arbovirus Persistence and Selection of Persistent Variants Following Chronic Infection in Aedine Mosquitoes: A Comparative Study Between Ae. Aegypti and Ae. Albopictus 30 Days Post Infection With Sindbis Virus

Lyski, Zoe Leah 01 January 2013 (has links)
In the present investigation two container breeding mosquitoes, Aedes aegypti and Aedes albopictus were exposed to Sindbis virus (SINV). Mosquitoes were proffered a viremic bloodmeal using a vertical membrane feeder in an attempt to infect females while preserving virus-gut interactions that are speculated to be responsible for amplification and selective roles encountered in nature. Cohorts of 50 mosquitoes of each species were exposed to SINV strain TR339 or EMEM in a bloodmeal and incubated in insectary conditions for 30 days. Once infected, the mosquito remains persistently infected for life, accumulating mutations in the virus RNA genome. Plaque size variants may indicate changes to the virus genome, therefore in this investigation TR339 persistent disseminated isolates (TR339-PDIs) were isolated from mosquito legs 30 days post infection (p.i.) and assayed for plaque size differences. These TR339-PDIs represent virus selected for by the whole mosquito. TR339-PDIs following a long term infection were used to study virus adaptations selected for during persistent infection of the mosquito host. The two mosquito species exhibited different host responses to SINV; survivorship, dissemination rates, and immunohistochemistry of mosquito midguts and hindguts were assayed at 30 days p.i. Aedes aegypti and Ae. albopictus along with SINV strain TR339 provide a good model system to study the selective pressures that occur within the whole mosquito. Greater knowledge of the mechanisms of virus persistence in the mosquito host is vital for controlling arthropod-borne disease at the vector level.
104

Infection and Dissemination of TaV-GFP Tagged Sindbis in Aedine Mosquitoes and Cell Lines

Saredy, Jason J 01 January 2015 (has links)
Arthropod-borne-viruses (arboviruses) pose a global threat due to their ability to be transmitted by hematophagous insects to vertebrate hosts resulting in a range of serious infectious diseases. Sindbis virus (SINV) is the prototype arbovirus of the genus Alphavirus in the family Togaviridae. The purpose of this study was to investigate the use of a fluorescent tagged reporter virus in both in vitro and in vivo environments. The fluorescent protein GFP was inserted between the Capsid and PE2 in the genome of TR339; SINV TaV-GFP (Wm. Klimstra Lab). This virus construct should have the same infectivity and virulence as wild type TR339, leaving a fluorescent ‘path’ in infected cells that may reveal virus transit. Virus stocks were grown in BHK-21 vertebrate cells and C7-10 mosquito cells. Two Aedes albopictus mosquito cell lines, C7-10 and C6/36, were then challenged with vertebrate and mosquito grown reporter virus. Evidence of GFP were seen as early as 6 hours post infection (p.i.) in all samples. Infected C7-10 cells with the vertebrate grown reporter virus were fixed for 1 hour in chilled 4% buffered paraformaldehyde; GFP was shown to be resilient to both fixation and light quenching. Ultimately, Ae. aegypti mosquitoes were challenged with a viremic bloodmeal at a titer of 107 PFU/ml and midguts were dissected over several days. The presence of GFP was observed in midgut columnar epithelial cells as early as day 3 p.i. and remained localized even at day 30 p.i. This is in agreement with published work on the interaction of TR339 in Ae. aegypti gut, signaling this viral construct as a means to visualize wild-type infection.
105

Genome-scaled molecular clock studies of invasive mosquitoes and other organisms of societal relevance

Zadra, Nicola 21 April 2022 (has links)
Molecular dating (or molecular clock) is a powerful technique that uses the mutation rate of biomolecules to estimate divergence times among organisms. In the last two decades, the theory behind the molecular clock has been intensively developed, and it is now possible to employ sophisticated evolutionary models on genome-scaled datasets in a Bayesian framework. The molecular clock has been successfully applied to virtually all types of organisms and molecules to estimate timing of speciation, timing of gene duplications, and generation times: this knowledge allows contextualizing past and present events in the light of (paleo)ecological scenarios. Molecular clock studies are routinely used in evolutionary and ecological studies, but their use in applied fields such as agricultural and medical entomology is still scarce in particular because of a paucity of genome data. Genome-scaled clocks have been successfully applied, for example, to various model organisms such as Anopheles and Drosophila, as well as to invasive mosquitoes Aedes aegypti and Aedes albopictus. Many other invasive pests are emerging worldwide aided by global trade, increased connectivity among countries, lack of prevention, and flawed invasive species management. Among them, there is Aedes koreicus and Aedes japonicus, two invasive mosquito species which are monitored for public health concerns because of their harboured human pathogenic viruses. For these, as well as for other insects of societal relevance, such as the parasitoid Trissolcus japonicus, there is a paucity of gene markers and no genome data for large scale molecular clock studies. Invasive pests are typically studied using microevolutionary approaches that tackle events at an intraspecific level: these approaches provide important information for the pest management, for example, by revealing invasion routes and insecticide resistances. Approaches that tackle the deep-time evolution of the pest, such as the molecular clock, are instead less used in pest science. Many important traits associated with invasiveness have evolved by speciation over a long time frame: the molecular clock can reveal the paleo-ecological conditions that favoured these traits helping a better understanding of pest biology. Molecular clock, when coupled with phylogenomics, can further identify genes and patterns that characterize the pest: this knowledge can be used to enhance management practices. Although this is a data-driven thesis, its major aim is to provide new results to demonstrate the utility of the molecular clock in pest science. This has been done by systematically apply the molecular clock to various neglected organisms of medical and agricultural relevance. To this aim, I generated new genome data and/or assembled the largest genome-scaled data to date. I studied the molecular clock in mosquitoes, focusing on the Aedini radiation (Chapter 2) and identified a strong incongruence between the mitochondrial and nuclear phylogeny for what concerns their molecular clock. This result highlighted the importance of employing genome scaled data for these species to exclude stochastic effects due to poor/inaccurate sampling in clock studies. To tackle the absence of data, I further assembled the whole mitogenome of emerging invasive species Aedes koreicus and Aedes japonicus with the aim of producing useful data for molecular typing and of inferring divergence estimates using whole mitogenomes (Chapter 3). Dated phylogenies point toward more recent diversification of Aedini and Culicini compared to estimates from previous works, addressing the issue of taxon sampling sensitivity in dated phylogeny. Although it is possible to perform molecular clock studies on single/few gene markers, the current trend is to couple this methodology with genome-scaled datasets to reduce the stochastic effect of using few genes. For this reason, I sequenced the draft genome of A. koreicus and A. japonicus (Chapter 4). The assemblies were extremely fragmented, highlighting the problem of sequencing large genomes using short reads. The assemblies provided, however enough information for genome skimming allowing extraction of BUSCO genes for downstream analyses, whole mitogenome assemblies (used in Chapter 3), and characterisation of the associated metagenome. These data need to be integrated by long reads; it provides, however a first framework to investigate the genome evolution of these species. I further sequenced and assembled the genome of Trissolcus japonicus, the parasitoid wasp of the invasive pest Halyomorpha halys. To elucidate its divergence, estimate and define an intraspecific typing system to differentiate strains for biocontrol strategies, I reconstructed the mitochondrial genomes of two populations: the mitogenomes were surprisingly identical, suggesting that they belong to the same de facto population. I further provide a detailed clock investigation of Zika, a virus harboured and transmitted by some Aedes species (Chapter 5). Using the largest set of genomes to date, I could set the origin of ZIKV in the middle age and its first diversification in the mid-19th century. From a methodological point of view, the clocking of this virus highlighted the importance of checking for recombination and for cell-passages to obtain correct divergence estimates. I finally show my contributions to molecular clock studies of three other invasive species (Chapter 6): I helped disentangle the divergence times of Bactrocera, a genus of invasive fruit files pest of agriculture; I contributed in performing a phylogenomics study of opsin genes in Diptera; I used chloroplast and nuclear genome data to reconstruct the divergences of the invasive reed Arundo. In the various Chapters of my thesis, I highlighted the limits and the problems of current molecular clock methodologies and identified the best practices for different types of organisms in order to develop a cross-discipline understanding of the molecular clock techniques. The various results presented in this thesis further demonstrate the utility of the molecular clock approach in pest studies.
106

Population Dynamics and Community Structure of Mosquitoes (Diptera: Culicidae) Recorded in Denton, Texas from 2005 to 2015

Hambrick, Bethany Lynn 05 1900 (has links)
A population survey was conducted on the mosquito species recorded in Denton, Texas for the years of 2005 to 2015. Data used in this project were obtained from an ongoing, long-term surveillance program led by the City of Denton and conducted through the University of North Texas. Research focused on the population dynamics and community structure of mosquitoes collected within urban areas of Denton, Texas in relation to certain environmental variables. A total of 80,837 female mosquitoes were captured and represented 38 species found under the following genera: Aedes, Anopheles, Coquillettidia, Culex, Culiseta, Mansonia, Orthopodomyia, Psorophora, Toxorhynchites, and Uranotaenia. Culex quinquefasciatus was the most abundant species followed by Aedes vexans. Seasonal patterns of the most abundant species revealed high variability throughout the study. Container breeders were most abundant in August and those that breed in floodwaters were most abundant in the months of May and September. Samples were tested for arbovirus presence through the Texas Department of State Health Services in Austin, Texas and multiple pools tested positive for West Nile virus throughout the study. Stepwise multiple regression and Spearman's rank correlation analyses were performed to examine the relationship between the mosquito community and environmental variables. Data revealed that temperature, precipitation, and dew point were the most important variables influencing the mosquito population in the City of Denton.
107

Viral metagenomics and phylogenomics for One Health

Silverj, Andrea 25 March 2024 (has links)
In recent years, the world has faced major health challenges, from the rise of antibiotic resistance to the emergence of new pathogens with pandemic potential. This highlights the importance of considering human health as inextricably intertwined with that of other animals and the environment in which they live. This paradigm is known as “One Health”, which is the integration of environmental sciences, veterinary science, and medicine. Within this perspective, viruses, the most abundant biological entities on Earth, play a central role in connecting different organisms, deeply influencing the health of their hosts. Despite their great importance, most viruses are still poorly understood, mainly because of the technical and economic limitations posed by isolation, cultivation, and single colony sequencing. However, recently developed genomic technologies offer a cheaper and more sensitive alternative to study viruses, allowing a better integration of data from various sources and making it possible to explore how they circulate among different hosts and environments. In this thesis, I hypotesise that, by combining different classes of genomic methods with One Health practices, it is possible to reveal much more of the entire picture of viral diversity and evolution that by simply using them in a separated way. I show that this is the case for each one of the scientific questions addressed in this work, which are organised in three main chapters: - In the second chapter I analysed 22 metatranscriptomes from tick samples from different parts of Italy, obtaining a set of 91 viral contigs for which I reconstructed the phylogeny, with the aim to identify the presence of possible pathogens and characterise the unexplored viral diversity in the country. This analysis not only clarified the molecular epidemiology of well-known pathogens such as Tick-borne encephalitis virus, but also allowed the discovery of at least 10 novel viral species. - In the third chapter, I investigated the origin and spread of West Nile virus, an emerging pathogen causing neurological disease worldwide. The goal was to expand the current knowledge of this virus by increasing the number of sequenced genomes and to reconstruct how the virus moved between Africa and Europe. Phylogeographic and phylodynamic methods showed that this pathogen originated in Africa and repeatedly invaded the European continent, revealing the dynamics of its evolution through space and time. - In the last chapter, I contributed to obtaining a set of DNA phages assembled from human microbiomes and viromes by manual curation and comparative genomics and developed a new approach to study their evolution in relation to their bacterial hosts. I found that the strength of co-phylogenetic patterns between viruses and their hosts is generally weak, suggesting that their ecological relationships emerge on short evolutionary timescales. Taken together, these results show how the integration of viral metagenomics and phylogenomics in One Health is essential to answer fundamental questions about the diversity of viruses and how they spread and evolve. Furthermore, the methods and protocols developed in these studies can be applied to similar cases, allowing a systematic exploration of many other datasets to expand our knowledge of the virosphere. This information can be used to implement containment strategies, public health policies, therapies, and biotechnologies.
108

Les caractéristiques environnementales du risque d’exposition aux arbovirus au Québec

Rocheleau, Jean-Philippe 09 1900 (has links)
Les arboviroses représentent un fardeau sanitaire considérable et croissant à l’échelle mondiale. La complexité des facteurs biotiques et abiotiques qui interviennent dans la transmission de ces arbovirus pose un défi de taille aux scientifiques qui tentent de comprendre, de modéliser ou d’anticiper leur transmission ainsi qu’aux intervenants de santé publique qui ont la responsabilité de surveiller, d’évaluer et gérer le risque que posent les arbovirus pour la santé des populations. Cette étude visait à estimer et caractériser le risque d’exposition à plusieurs arbovirus suspectés d’être actifs et émergents au Québec mais dont la distribution avait peu ou n’avait pas été étudiée au Québec : le virus du Nil occidental (VNO), le virus de l’encéphalite équine de l’est (VEEE) et deux virus du sérogroupe de la Californie (VSGC), le virus de Jamestown Canyon (VJC) et le virus du lièvre d’Amérique (VLA). Basée notamment sur l’hypothèse selon laquelle les animaux d’espèces différentes qui partagent un environnement commun partagent également un risque environnemental commun, cette étude visait également à évaluer si les populations d’animaux de compagnie pouvaient aider à estimer et caractériser le risque d’infection arbovirale chez l’humain. L’échantillonnage sérologique de populations humaines, canines et équines du sud-ouest du Québec a permis d’évaluer et de comparer la séroprévalence aux arbovirus étudiés chez chacune de ces trois espèces. Les estimations de séroprévalence ont révélé un niveau d’activité arbovirale significative pour chacun des arbovirus. Des différences ont été remarquées quant au pourcentage de sujets séropositifs chez chacune des espèces. Les facteurs environnementaux ayant une influence sur le risque d’infection par le VEEE ont été modélisés à partir de données sérologiques et cliniques chez les chevaux. Les milieux humides boisés ont été identifiés comme les principaux environnements à risque pour le VEEE au Québec alors que les zones agricoles ont été identifiées comme des environnements protecteurs. Les facteurs environnementaux ayant un impact sur le risque d’infection par le VNO ont été modélisés à partir des données sérologiques chez le chien et des données cliniques agrégées chez l’humain. Cette modélisation a suggéré un risque singulièrement plus élevé en zone agricole chez le chien et un risque plus faible en zone forestière chez l’humain, des facteurs rarement identifiés dans la littérature Nord-Américaine. Les facteurs environnementaux et individuels ayant un impact sur le risque d’infection par les VSGC chez l’humain et le chien ont par la suite été modélisés à partir des données sérologiques chez ces deux espèces. D’après nos modèles, le risque d’infection par ces virus serait supérieur en zone forestière et le degré d’exposition aux piqures de moustiques serait un facteur déterminant du risque d’infection chez les deux espèces. Cette étude a permis de bonifier de façon substantielle le portrait de l’activité arbovirale au Québec. Elle a permis de caractériser la distribution du risque et a fourni des données probantes pouvant soutenir la recherche ainsi que la planification des interventions en santé publique. La méthodologie utilisée dans le cadre de cette étude supporte la pertinence de l’approche « One Health » pour l’étude des maladies vectorielles émergentes. / Arboviral infections represent a considerable and growing health burden globally. The complexity of biotic and abiotic factors involved in the transmission of these arboviruses pose a challenge to scientists trying to understand, model or anticipate arboviral transmission as well as to public health authorities who have the responsibility to monitor, assess and manage the public health risk posed by arboviruses. This study aimed at estimating and characterizing the risk of exposure to several arboviruses suspected of being active and emerging in Québec but whose distribution had not been studied thoroughly in Québec: West Nile virus (WNV), eastern equine encephalitis virus (EEEV) and two viruses of the California serogroup (CSG), Jamestown Canyon virus (JCV) and Snowshoe hare virus (SHV). Based on the assumption that animals of different species sharing a common environment also share similar environmental risk, this study also aimed to assess whether some populations of domestic animals could help to estimate and characterize the risk of arboviral infection in humans. Serological sampling of human, canine and equine populations from southwestern Québec was used to evaluate and compare the seroprevalence to the selected arboviruses in each of these three species. Seroprevalence estimates showed a significant level of arboviral activity for all arboviruses. Differences were noted in the percentage of seropositive individuals in each species. Environmental factors that influence the risk of infection by EEEV were modeled based on serological and clinical data in horses. Wooded wetlands were identified as the main risk environments for EEEV in Québec while agricultural areas were identified as protective environments. Environmental factors affecting the risk of WNV infection were modeled based on serological data in dogs and aggregated clinical data in humans. These models suggested a higher risk in agricultural areas in dogs and a lower risk in forest areas in humans, two factors rarely identified in the North American literature. Environmental and individual factors affecting the risk of infection by CSGV in humans and dogs have subsequently been modeled based on serological data in these two species. According to our models, the risk of infection with these viruses would be higher in forested areas and the degree of exposure to mosquito bites would be a risk factor for infection in both species. This study substantially enhanced the comprehension of arboviral activity in Québec. It allowed for characterizing the distribution of risk and provided evidence that may support research and planning of public health interventions. The methodology used in this study supports the relevance of the "One Health" approach for the study of emerging vector-borne diseases.
109

Vigilância entomológica de vetores de arbovírus na cidade de São Paulo: análise espaço temporal de criadouros, de acordo com fatores sazonais e socioeconômicos, no período de 2012 a 2016 / Entomological surveillance of arbovirus vectors in the city of São Paulo: analysis of breeding sites, according to seasonal and socioeconomic factors, between 2012 and 2016

Diniz, Patricia Placoná 13 June 2018 (has links)
Introdução: Conhecer e monitorar fatores associados a transmissão de arboviroses são um grande desafio para os gestores de saúde pública e também uma necessidade para regiões onde há registro da circulação de arbovírus e a presença de vetores. Objetivos: Identificar os principais grupos de recipientes que podem se tornar ou são criadouros de mosquitos vetores no Município de São Paulo e verificar se os mesmos sofrem influências de fatores sazonais e socioeconômicos em sua distribuição. Método: Foram levantados dados das inspeções realizadas nas atividades de vigilância e controle de Aedes aegypti no período de 2012-2016, por Supervisão Técnica de Saúde e para o município. Em seguida foram construídos grupos de recipientes para avaliar predominância nas diferentes condições de encontro (existente, com água, com larva). Os indicadores gerados foram utilizados para testar diferenças significativas das frequências entre as estações do ano e analisar correspondência entre incidência de casos dengue e predominância de grupos de criadouros. Posteriormente, foi realizada análise de agrupamento por fatores socioeconômicos para identificar diferenças na distribuição dos grupos de recipientes. Para as análises de variância foi utilizado o teste não paramétrico de Kruskal-Wallis. Resultados: O grupo de recipientes móveis foi o potencial criadouro mais frequente em todos os anos, seguido dos grupos planta e pneus. Móvel e planta foram os criadouros mais frequentes para o município. O grupo móveis, apesar de numeroso, não foi o mais colonizado. Por outro lado, os depósitos para armazenamento de água tiveram baixa frequência, porém alta proporção de colonização. A sazonalidade influenciou na distribuição de recipientes com água e com larva, sendo que as maiores frequências ocorreram no verão e outono. A proporção de imóveis tendo recipientes com água aumentou de acordo com o tempo, principalmente em 2015. O grupo que teve maior incremento do índice nesse período foi o de depósito não ligado à rede. Foram gerados cinco grupos de STS por condições socioeconômicas, nos quais houve diferenças no padrão de distribuição de potenciais criadouros e criadouros. Regiões com melhor condição socioeconômica apresentaram menor frequência dos indicadores, mas não necessariamente menor risco de transmissão de dengue no período avaliado. Conclusões: Os principais grupos de criadouros mais frequentes no Município de São Paulo dentro do período analisado foram os de menor tamanho, principalmente os do tipo móvel. Reservatórios de maior tamanho e destinados ao armazenamento de água demonstraram importância na proporção de colonização e tiveram sua frequência aumentada no período da crise hídrica do abastecimento. Fatores sazonais e condições socioeconômicas influenciaram a distribuição de criadouros em São Paulo. Para melhor direcionamento das ações de prevenção e controle de vetores, analises sistemáticas e continuas por regiões devem ser realizadas. / Introduction: Knowing and controlling factors associated with arbovirus transmission is a major challenge for public health managers, but it is necessary for regions where arbovirus circulation and the presence of vectors are present. Objectives: To identify the main groups of containers that can become or are breeding sites of mosquito vectors in the São Paulo Municipality and verify if their distribution are influenced by seasonal and socioeconomic factors. Method: Data were collected from the inspections carried out in the surveillance and control activities of Ae. aegypti in the period 2012-2016, by Health Technical Supervision and county. Groups of containers were then created to evaluate predominance in the different checked conditions (existing, with water, with larvae). The generated indicators were used to test significant differences of the frequencies between the seasons of the year and to analyze correspondence between incidence of dengue cases and predominance of breeding sites groups. After, a socioeconomic grouping analysis was performed to identify differences in the distribution of groups of recipients. The Kruskal-Wallis non-parametric test was used for the variance analysis. Results: The group of mobile containers was the most frequent potential breeding site in all the years, followed by container plants and tires groups. Mobile and plant were the most frequent breeding sites for the county. The mobile group, although numerous, was not the most colonized. On the other hand, deposits for water storage had a low frequency, but a high proportion of colonization. Seasonality influenced the distribution of water and larvae containers, with the highest frequencies occurring in summer and fall. The proportion of buildings having containers with water increased over time, especially in 2015. The group that had the largest increase in the index in this period was the deposit not connected to the water supply network. Five Health Technical Supervision groups were generated by socioeconomic conditions, in which there were differences in the pattern of distribution of potential breeding sites and breeding sites for mosquitoes. Regions with better socioeconomic status had lower frequency of indicators, but not necessarily a lower risk of dengue transmission in the period evaluated. Conclusions: The main breeding sites groups most frequent in the city of São Paulo during the analyzed period were the smaller groups, mainly those of the mobile type. Larger reservoirs destined to water storage showed importance in the proportion of colonization and had their frequency increased in the period of the water supply crisis. Seasonal factors and socioeconomic conditions influenced the distribution of breeding sites in. To better target vector prevention and control actions, systematic and continuous analyzes by regions should be performed.
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Dispers?o da febre amarela entre primatas n?o-humanos durante epizootia no Rio Grande do Sul : entendendo o papel de fatores abi?ticos, da paisagem e da presen?a de animais imunes para propor cen?rios futuros de reemerg?ncia da doen?a

Almeida, Marco Ant?nio Barreto de 22 March 2018 (has links)
Submitted by PPG Zoologia (zoologia-pg@pucrs.br) on 2018-08-01T18:22:00Z No. of bitstreams: 1 Almeida MAB___TESE___VERS?O FINAL.pdf: 2953118 bytes, checksum: 99cbefa9c38c7969abce4bafc4b20d54 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-08-02T17:55:11Z (GMT) No. of bitstreams: 1 Almeida MAB___TESE___VERS?O FINAL.pdf: 2953118 bytes, checksum: 99cbefa9c38c7969abce4bafc4b20d54 (MD5) / Made available in DSpace on 2018-08-02T18:39:41Z (GMT). No. of bitstreams: 1 Almeida MAB___TESE___VERS?O FINAL.pdf: 2953118 bytes, checksum: 99cbefa9c38c7969abce4bafc4b20d54 (MD5) Previous issue date: 2018-03-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Nonhuman primates (NHP) are susceptible to many arboviruses, including the yellow fever (YF) virus. Although native to Africa, this virus found susceptible NHP and competent mosquito vectors for maintaining its transmission in American forests. A high sensitivity of NHP to YF led health agencies to monitor these animals as a way of monitoring the disease in Brazil. The State of Rio Grande do Sul (RS) began this surveillance in 2002, which has detected the arboviruses Oropouche and Saint Louis (SLEV) and a YF epizootic that killed more than 2,000 NHP (Alouatta caraya and A. guariba clamitans) between 2008 and 2009. The objectives of this PhD thesis research were to generate models of niche suitability for YF based on that epizootic and prospect arboviruses in NHP in northwestern RS. The maximum entropy algorithm - Maxent was used to generate distribution models of Alouatta spp. and the mosquito vector Haemagogus leucocelaenus. Together with climatic, topographic and vegetative variables, these models served as predictor layers to model the occurrence of the disease based on the points of death of NHP of YF. The most influential variables in the YF models were the variation in air humidity, distribution of Alouatta spp. and maximum wind speed followed by mean annual rainfall and maximum temperature. Therefore, support for the influence of the rainfall regime and the ambient temperature on the cycle of jungle YF was found. Wind speed and direction can play an important role in the dispersal of infected mosquitoes and, consequently, the virus. The models based on the occurrence of dead NHP in the first months of the epizootic identified suitable areas to where the disease spread a few months later. In addition, 19 arboviruses were prospected in 40 blood (viral isolation and PCR) and serum (hemagglutination inhibition and neutralization tests [NT]) samples collected from 26 black howler monkeys (A. caraya) belonging to three populations in four field campaigns in the municipality of Santo Ant?nio das Miss?es, RS, between 2014 and 2016. There was no detection of circulating virus, but antibodies to Flavivirus SLEV and Ilh?us and Phlebovirus Icoaraci was found by NT. Evidence of the contact with Ilh?us and Icoaraci are the southernmost records in Brazilian NHP. An increase in antibodies to SLEV detected between two consecutive captures of the same individual is compatible with a recent contact with the virus. An adult male captured in one of the areas presented concomitant infection by the Oropouche, SLEV and YF viruses by NT. Further studies are necessary to understand the role played by NHP and other vertebrates in the circulation of arboviruses in the region, to assess potential risks to NHP and public health, and to identify the driving forces responsible for the dispersal of the YF virus during epizootics in wildlife populations. / Os primatas n?o-humanos (PNH) s?o suscet?veis a diversos arbov?rus, incluindo o v?rus da febre amarela (FA). Embora origin?rio da ?frica, esse v?rus encontrou PNH suscet?veis e mosquitos vetores competentes para sua transmiss?o em matas nas Am?ricas. Uma alta sensibilidade dos PNH ? FA levou ?rg?os de sa?de a monitorar esses animais como forma de vigiar a doen?a no Brasil. O Estado do Rio Grande do Sul (RS) iniciou essa vigil?ncia em 2002, a qual detectou os arbov?rus Oropouche e Saint Louis (SLEV) e uma epizootia de FA que matou mais de 2000 PNH (Alouatta caraya e A. guariba clamitans) entre 2008 e 2009. A presente tese de doutorado teve como objetivos gerar modelos de adequabilidade ambiental para FA com base nessa epizootia e prospectar arbov?rus em PNH no noroeste do RS. Foi utilizado o algoritmo de m?xima entropia ? Maxent para gerar modelos de distribui??o de Alouatta spp. e do mosquito vetor Haemagogus leucocelaenus. Esses modelos serviram como camadas preditoras para, junto a vari?veis clim?ticas, topogr?ficas e vegetacionais, modelar a ocorr?ncia da doen?a baseada nos pontos de morte de PNH por FA. As vari?veis mais influentes nos modelos da FA foram a varia??o na umidade do ar, a distribui??o de Alouatta spp. e a velocidade m?xima dos ventos, seguidas pela precipita??o m?dia anual e a temperatura m?xima. Portanto, foi confirmado suporte para a influ?ncia do regime de chuvas e da temperatura ambiente no ciclo da FA silvestre. A velocidade e a dire??o do vento devem desempenhar um importante papel na dispers?o de mosquitos infectados e, consequentemente, do v?rus. Os modelos baseados na distribui??o espacial de PNH mortos nos primeiros meses da epizootia identificaram ?reas adequadas para onde a doen?a avan?ou poucos meses mais tarde. Tamb?m foram prospectados 19 arbov?rus em 40 amostras de sangue (isolamento viral e PCR) e soro (inibi??o da hemaglutina??o e testes de neutraliza??o [NT]) coletadas em quatro campanhas de campo entre 2014 e 2016 de 26 bugios-pretos (A. caraya) de tr?s popula??es no munic?pio de Santo Ant?nio das Miss?es, RS. N?o houve detec??o de v?rus circulante, mas sim de anticorpos para os Flavivirus SLEV e Ilh?us e o Phlebovirus Icoaraci por NT. As evid?ncias de contato com Ilh?us e Icoaraci s?o as primeiras em PNH no extremo sul do Brasil. Um aumento de anticorpos para SLEV detectado entre duas capturas consecutivas do mesmo indiv?duo ? compat?vel com um contato recente com o v?rus. Um macho adulto capturado em uma das ?reas apresentou infec??o concomitante pelos v?rus Oropouche, SLEV e FA por NT. Mais estudos s?o necess?rios para compreender o papel de PNH e outros vertebrados na circula??o de arbov?rus na regi?o, avaliar poss?veis riscos para PNH e a sa?de humana e identificar as for?as motrizes respons?veis pela dispers?o do v?rus da FA durante epizootias em popula??es selvagens.

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