Understanding the ecology and epidemiology of tick-borne diseases requires detailed knowledge of the complex interactions among the tick vector, the microorganisms they carry and the vertebrate hosts used by ticks, as well as the environmental conditions experienced by all three groups of organisms in this triad. In this thesis, I addressed questions relating to the biology and vector ecology of the Rocky Mountain wood tick (Dermacentor andersoni) and the American dog tick (Dermacentor variabilis). Comparisons were made of the distribution of both tick species, the vertebrate hosts used by immature ticks, and the types and prevalence of bacteria in individual ticks from multiple localities near the northern extent of their geographic ranges in western Canada. The results revealed that the distributions of both D. andersoni and D. variabilis have expanded since the 1960s, and there is now a broad zone of sympatry in southern Saskatchewan. In this zone of sympatry, D. andersoni and D. variabilis immatures were found to use the same species of small mammals as hosts and, in some cases, the same host individuals. This provides for the possibility of cross-transmission of bacteria from one tick species to the other. Bacteria of several genera (e.g. Rickettsia, Francisella, Arsenophonus and Anaplasma) were detected in D. andersoni and/or D. variabilis, some of which represented new tick-bacteria associations. However, most bacterial species were highly host (tick)-specific, except for three examples of apparent host switching from one tick species to the other at localities where the two tick species occurred in sympatry. The findings of this thesis provide a basis for understanding microbial transmission, the structure of tick-borne microbial communities, the risk of tick-borne disease in humans and animals, and the vector potential of D. andersoni and D. variabilis in geographical areas where they have not been studied previously.

Understanding the ecology and epidemiology of tick-borne diseases requires detailed knowledge of the complex interactions among the tick vector, the microorganisms they carry and the vertebrate hosts used by ticks, as well as the environmental conditions experienced by all three groups of organisms in this triad. In this thesis, I addressed questions relating to the biology and vector ecology of the Rocky Mountain wood tick (Dermacentor andersoni) and the American dog tick (Dermacentor variabilis). Comparisons were made of the distribution of both tick species, the vertebrate hosts used by immature ticks, and the types and prevalence of bacteria in individual ticks from multiple localities near the northern extent of their geographic ranges in western Canada. The results revealed that the distributions of both D. andersoni and D. variabilis have expanded since the 1960s, and there is now a broad zone of sympatry in southern Saskatchewan. In this zone of sympatry, D. andersoni and D. variabilis immatures were found to use the same species of small mammals as hosts and, in some cases, the same host individuals. This provides for the possibility of cross-transmission of bacteria from one tick species to the other. Bacteria of several genera (e.g. Rickettsia, Francisella, Arsenophonus and Anaplasma) were detected in D. andersoni and/or D. variabilis, some of which represented new tick-bacteria associations. However, most bacterial species were highly host (tick)-specific, except for three examples of apparent host switching from one tick species to the other at localities where the two tick species occurred in sympatry. The findings of this thesis provide a basis for understanding microbial transmission, the structure of tick-borne microbial communities, the risk of tick-borne disease in humans and animals, and the vector potential of D. andersoni and D. variabilis in geographical areas where they have not been studied previously.

Objetivo. Conhecer os aspectos ecológicos e biológicos da população de Mansonia humeralis em área sob impacto de inundação da Represa Porto Primavera, Município de Presidente Epitácio, Estado de São Paulo, Brasil, visando contribuir no entendimento da capacidade vetora desta população. A dominância dessa população entre outras espécies de culicídeos, que compõem a fauna local, representa preocupação em saúde pública, diante da possibilidade de transmissão de agentes patogênicos e de incômodo à população humana. Métodos. No sítio JB, culicídeos adultos foram coletados mensalmente por 15 meses, em cada um dos períodos anterior e posterior às duas inundações da Represa Porto Primavera, e por 24 meses após a 2ª inundação, na fazenda Santo Antônio. As técnicas de coleta utilizadas foram Aspiração pela manhã, Técnica Atrativa Humana de 24 horas, Armadilha de Shannon, Armadilha CDC e Técnica Atrativa Humana em torno do crepúsculo vespertino. Foram levadas em conta as influências de temperatura e chuva na variabilidade temporal da população estudada. Para a análise do impacto ambiental na população de Ma. humeralis foram utilizados índices de riqueza, diversidade, dominância, abundância e similaridade, testes estatísticos paramétricos, não paramétricos e correlação. Para a atividade hematofágica horária foi calculada a média de Williams, para a dispersão do raio de vôo a média harmônica e o modelo de regressão linear simples e para a paridade o qui-quadrado. Resultados. No sítio JB, no período do pré-impacto, Ma. humeralis representou 3,1%. No período pós-impacto após a 1ª inundação Ma. humeralis representou 59,6% e após a 2ª inundação 53,8%, indicando expressiva dominância dessa espécie e redução da riqueza e diversidade dos outros culicídeos. Houve maior densidade populacional de Ma. humeralis no outono e inverno no pré-enchimento, no inverno e na primavera após a 1ª inundação e na primavera após a 2ª inundação. Ma. humeralis posicionou-se entre as espécies mais abundantes e foi similar na fauna do período pós-impacto. A atividade hematofágica de Ma. humeralis foi nas 24 horas, mas de maior freqüência no intervalo do 1º pós-crepúsculo e das 18:00 às 24:00 horas. Na fazenda Santo Antônio a maior densidade populacional de Ma. humeralis ocorreu no verão e na primavera e as médias de riqueza, diversidade e dominância foram próximas aos valores encontrados no pré-enchimento do sítio JB, com a Armadilha de Shannon no crepúsculo vespertino. Em relação a paridade Ma. humeralis apresentou mais fêmeas oníparas no outono. Ma. humeralis apresentou baixa dispersão no raio de vôo. Conclusões. Com a construção da Usina Hidrelétrica de Porto Primavera e o represamento do Rio Paraná, estudos realizados em Presidente Epitácio, na margem esquerda do mesmo e do Rio do Peixe, mostraram redução na diversidade e riqueza da fauna adulta Culicidae, vista pela aplicação de diferentes técnicas de coleta. A dominância de Ma. humeralis mostrou que o impacto ambiental ocorrido na área favoreceu seu desenvolvimento indicado pela sua abundância e sua permanência na fauna similar, após a inundação. As densidades mais elevadas para Ma. humeralis, associada as plantas aquáticas, parece estar ligada com as águas renováveis dos grandes reservatórios. Evidenciou-se tendência antropofílica e atividades hematofágicas predominantemente crepuscular e noturna para Ma. humeralis. A baixa dispersão no raio de vôo encontrada em Ma. humeralis, não permite concluir que esta população não se dispersaria para maiores distâncias em busca de fontes sangüíneas. É relevante o monitoramento de certas populações de culicídeos favorecidas pela formação de represas, uma vez que há exposição freqüente do homem às margens dos rios, devido às atividades de pesca, caça, lazer e moradia. / Objective. To assess the ecological and biological aspects of the population of Mansonia humeralis, in area under the Porto Primavera Dam flooding impact, Presidente Epitácio municipality, São Paulo State, Brazil, in order to understand the vector capacity of this population. This population dominance over other Culicidae species that constitute the local fauna represents public health concern because of the possibility of transmission of pathogenic agents and nuisance to human populations. Methods. In the JB Ranch adults Culicidae were monthly captured for 15 months, on each of the previous and posterior periods of the two flooding events of the Porto Primavera Dam, and for the 24 months after the second flooding in the Santo Antônio Farm. Captures were undertaken by morning Aspiration, Human Attraction Technique for 24 hours, Shannon traps, CDC light traps and Human Attraction Technique near sunset. Temperature and rainfall were accounted for temporal variation of the studied population. To environmental impact analysis on Ma. humeralis population richness, diversity, dominance, abundance and similarity, indexes and parametric and non-parametric statistics and correlation were used, blood feeding time activity was calculated by the Williams\' Mean, harmonic mean and simple linear regression model to flight range dispersal were used and to parity, chi-square was used. Results. In the JB Ranch, on the pre-impact period, Ma. humeralis represented 3.1%. After the first flooding Ma. humeralis represented 59.6% and after the second flooding it represented 53.8%, indicating significative dominance of this species and richness and diversity reduction of other Culicidae. Larger population densities of Ma. humeralis were found in the autumn and winter on the pre-filling of the Dam, in the winter and the spring after the first flooding and in the spring after the second flooding. Ma. humeralis was among the more abundant species and was similar on the fauna post-impact period. Blood feeding time activity of Ma. humeralis was practically of 24 hours, but its higher frequency was on the first post-crepuscular interval and on the 18:00 to 24:00 hours interval. In the Santo Antônio Farm, the largest populational density of Ma. humeralis occurred in the summer and in the spring and the means for species diversity, richness and dominance were close to the values found in the pre-filling in the JB Ranch, with captures undertaken by Shannon traps during sunset. As for parity, more parous females were found in the autumn. Ma. humeralis presented low flight radius dispersal. Conclusions. The construction of the Porto Primavera Hydroelectric Power Plant and the dam of the Paraná River, in the studies conducted in Presidente Epitácio, on the left margin of this river and the Peixe River, presented a reduction on the diversity and richness of the Culicidae fauna undertaken by different capture techniques. The dominance of Ma. humeralis showed that the environmental impact on the area supported its development as indicated by its abundance and permanence on the similar fauna, after the two flooding events. The highest densities of Ma. humeralis, associated with aquatic plants, seems to be connected with the renewable waters of the great reservoirs. Ma. humeralis showed a tendency to anthropophily, with the blood feeding activity preferably at sunset and at night. The low flight dispersal, does not allow to conclude if Ma. humeralis would not fly higher distances in search of blood sources. It is relevant to monitor some Culicidae populations favoured by dam constructions, once there is frequent man exposition on the rivers\' edges, due to fishing activities, hunting, leisure and dwelling.

Objetivo. Conhecer os aspectos ecológicos e biológicos da população de Mansonia humeralis em área sob impacto de inundação da Represa Porto Primavera, Município de Presidente Epitácio, Estado de São Paulo, Brasil, visando contribuir no entendimento da capacidade vetora desta população. A dominância dessa população entre outras espécies de culicídeos, que compõem a fauna local, representa preocupação em saúde pública, diante da possibilidade de transmissão de agentes patogênicos e de incômodo à população humana. Métodos. No sítio JB, culicídeos adultos foram coletados mensalmente por 15 meses, em cada um dos períodos anterior e posterior às duas inundações da Represa Porto Primavera, e por 24 meses após a 2ª inundação, na fazenda Santo Antônio. As técnicas de coleta utilizadas foram Aspiração pela manhã, Técnica Atrativa Humana de 24 horas, Armadilha de Shannon, Armadilha CDC e Técnica Atrativa Humana em torno do crepúsculo vespertino. Foram levadas em conta as influências de temperatura e chuva na variabilidade temporal da população estudada. Para a análise do impacto ambiental na população de Ma. humeralis foram utilizados índices de riqueza, diversidade, dominância, abundância e similaridade, testes estatísticos paramétricos, não paramétricos e correlação. Para a atividade hematofágica horária foi calculada a média de Williams, para a dispersão do raio de vôo a média harmônica e o modelo de regressão linear simples e para a paridade o qui-quadrado. Resultados. No sítio JB, no período do pré-impacto, Ma. humeralis representou 3,1%. No período pós-impacto após a 1ª inundação Ma. humeralis representou 59,6% e após a 2ª inundação 53,8%, indicando expressiva dominância dessa espécie e redução da riqueza e diversidade dos outros culicídeos. Houve maior densidade populacional de Ma. humeralis no outono e inverno no pré-enchimento, no inverno e na primavera após a 1ª inundação e na primavera após a 2ª inundação. Ma. humeralis posicionou-se entre as espécies mais abundantes e foi similar na fauna do período pós-impacto. A atividade hematofágica de Ma. humeralis foi nas 24 horas, mas de maior freqüência no intervalo do 1º pós-crepúsculo e das 18:00 às 24:00 horas. Na fazenda Santo Antônio a maior densidade populacional de Ma. humeralis ocorreu no verão e na primavera e as médias de riqueza, diversidade e dominância foram próximas aos valores encontrados no pré-enchimento do sítio JB, com a Armadilha de Shannon no crepúsculo vespertino. Em relação a paridade Ma. humeralis apresentou mais fêmeas oníparas no outono. Ma. humeralis apresentou baixa dispersão no raio de vôo. Conclusões. Com a construção da Usina Hidrelétrica de Porto Primavera e o represamento do Rio Paraná, estudos realizados em Presidente Epitácio, na margem esquerda do mesmo e do Rio do Peixe, mostraram redução na diversidade e riqueza da fauna adulta Culicidae, vista pela aplicação de diferentes técnicas de coleta. A dominância de Ma. humeralis mostrou que o impacto ambiental ocorrido na área favoreceu seu desenvolvimento indicado pela sua abundância e sua permanência na fauna similar, após a inundação. As densidades mais elevadas para Ma. humeralis, associada as plantas aquáticas, parece estar ligada com as águas renováveis dos grandes reservatórios. Evidenciou-se tendência antropofílica e atividades hematofágicas predominantemente crepuscular e noturna para Ma. humeralis. A baixa dispersão no raio de vôo encontrada em Ma. humeralis, não permite concluir que esta população não se dispersaria para maiores distâncias em busca de fontes sangüíneas. É relevante o monitoramento de certas populações de culicídeos favorecidas pela formação de represas, uma vez que há exposição freqüente do homem às margens dos rios, devido às atividades de pesca, caça, lazer e moradia. / Objective. To assess the ecological and biological aspects of the population of Mansonia humeralis, in area under the Porto Primavera Dam flooding impact, Presidente Epitácio municipality, São Paulo State, Brazil, in order to understand the vector capacity of this population. This population dominance over other Culicidae species that constitute the local fauna represents public health concern because of the possibility of transmission of pathogenic agents and nuisance to human populations. Methods. In the JB Ranch adults Culicidae were monthly captured for 15 months, on each of the previous and posterior periods of the two flooding events of the Porto Primavera Dam, and for the 24 months after the second flooding in the Santo Antônio Farm. Captures were undertaken by morning Aspiration, Human Attraction Technique for 24 hours, Shannon traps, CDC light traps and Human Attraction Technique near sunset. Temperature and rainfall were accounted for temporal variation of the studied population. To environmental impact analysis on Ma. humeralis population richness, diversity, dominance, abundance and similarity, indexes and parametric and non-parametric statistics and correlation were used, blood feeding time activity was calculated by the Williams\' Mean, harmonic mean and simple linear regression model to flight range dispersal were used and to parity, chi-square was used. Results. In the JB Ranch, on the pre-impact period, Ma. humeralis represented 3.1%. After the first flooding Ma. humeralis represented 59.6% and after the second flooding it represented 53.8%, indicating significative dominance of this species and richness and diversity reduction of other Culicidae. Larger population densities of Ma. humeralis were found in the autumn and winter on the pre-filling of the Dam, in the winter and the spring after the first flooding and in the spring after the second flooding. Ma. humeralis was among the more abundant species and was similar on the fauna post-impact period. Blood feeding time activity of Ma. humeralis was practically of 24 hours, but its higher frequency was on the first post-crepuscular interval and on the 18:00 to 24:00 hours interval. In the Santo Antônio Farm, the largest populational density of Ma. humeralis occurred in the summer and in the spring and the means for species diversity, richness and dominance were close to the values found in the pre-filling in the JB Ranch, with captures undertaken by Shannon traps during sunset. As for parity, more parous females were found in the autumn. Ma. humeralis presented low flight radius dispersal. Conclusions. The construction of the Porto Primavera Hydroelectric Power Plant and the dam of the Paraná River, in the studies conducted in Presidente Epitácio, on the left margin of this river and the Peixe River, presented a reduction on the diversity and richness of the Culicidae fauna undertaken by different capture techniques. The dominance of Ma. humeralis showed that the environmental impact on the area supported its development as indicated by its abundance and permanence on the similar fauna, after the two flooding events. The highest densities of Ma. humeralis, associated with aquatic plants, seems to be connected with the renewable waters of the great reservoirs. Ma. humeralis showed a tendency to anthropophily, with the blood feeding activity preferably at sunset and at night. The low flight dispersal, does not allow to conclude if Ma. humeralis would not fly higher distances in search of blood sources. It is relevant to monitor some Culicidae populations favoured by dam constructions, once there is frequent man exposition on the rivers\' edges, due to fishing activities, hunting, leisure and dwelling.

Mosquito species of the Anopheles gambaie complex are the predominant vectors of malaria transmission throughout sub-Saharan Africa. These mosquitoes tend to be endophilic, as well as anthropophilic, making them prime candidates for disease transmission. Within the same region, related mosquito vectors play a significant role in the transmission of additional human and zoonotic diseases. Furthermore, mosquito nuisance biting is an immense issue that cannot be ignored in terms of its impact on African communities. Depending on the respective factors involved, mosquito control programs throughout the continent have attempted to tackle these issues in a multitude of ways. This research approached the issue by developing and integrating an American-style mosquito control district within the eastern Ugandan community of Papoli. The basic structure of such a district was blended with a community-based approach, employing local community members and leaders, thus ensuring an effective and sustainable program. A guide detailing all aspects and steps needed to properly develop and implement such a program is outlined.

Little is known about the tick populations found within the central Appalachian/southwestern region of Virginia. The main focus of this research was to better assess local tick communities in the central Appalachian-Southwestern region of Virginia, which was addressed by determining species diversity, habitat associations, seasonal phenology, pathogen prevalence, and ecological factors that influences tick presence and abundance. A field study was conducted from June 2019 - November 2020 across 8 counties and 3 habitat types. Forested habitats exhibited greater tick species diversity than pasture and urban habitats. Each tick species was observed to be associated with particular habitats. The presence of B. burgdorferi sensu stricto (causative agent of Lyme disease), the human variant of A. phagocytophilum (causative agent of human granulocytic anaplasmosis), and Powassan virus (the causative agent of Powassan encephalitis) were detected in collected field specimens, suggesting a significant threat to public health. The detection of Powassan virus RNA in local Ixodes scapularis ticks is the first evidence of this viral pathogen within the region. The overwintering abilities of ticks, whose populations are expanding or becoming more invasive, including Haemaphysalis longicornis, Amblyomma americanum, and Amblyomma maculatum, were examined through a combination of laboratory and field experiments. Amblyomma americanum and H. longicornis nymphal ticks had a lower supercooling temperature than adult ticks, suggesting their potential to overwinter better; A. maculatum nymphs had similar average supercooling temperatures as the other two species at nymphal stage. Via a field experiment, A. americanum, H. longicornis, and A. maculatum were subjected to natural elements of a Virginian winter in a two-factor design investigating elevation and potential insulation coverage. Elevation and insulation coverage were found to have no significant impact on the overwintering survival of H. longicornis and A. americanum. However, the life-stage of the tick was determined to be a significant factor that dictated the survival of ticks of these species. Overwintering survival of Amblyomma maculatum nymphs was influenced by insulation (proxied by leaf litter); which may be attributed to this tick's preference of drier climate. Low overwintering survival suggests that a tick may not be able to establish a permanent population within the area. / Master of Science in Life Sciences / Ticks can transmit many pathogens, bacteria or viruses that cause disease, to both humans and animals. Diseases associated with ticks can include Lyme disease, Human Anaplasmosis, Ehrlichiosis, Rocky Mountain spotted fever, as well as viral illnesses. The pathogens that cause these diseases are vectored by specific tick species. Currently, there are no published reports of tick species present within the central Appalachian/southwestern region of Virginia. A study to determine local tick populations presence and the factors influencing their maintenance in the environment was conducted. Additionally, field collected specimens were screened to assess pathogen prevalence within the region. I confirm the presence of Borrelia burgdorferi sensu stricto (causative agent for Lyme disease), Anaplasma phagocytophilum (causative agent for Human Granulocytic Anaplasmosis), and Powassan virus within Ixodes scapularis, commonly referred to as black-legged ticks. Habitat (forest, urban, pasture) was a significant influencing factor on the presence of I. scapularis, Amblyomma americanum, and Haemaphysalis longicornis (e.g., the latter species was predominantly found in pasture habitats). Secondly, I investigated how well three sympatric tick species would overwinter within the region. Survival of a tick is heavily dependent upon their ability to withstand desiccation, obtain a blood meal from a host, mate, and reproduce. Certain ticks may be limited to certain regions based on elevation, temperature, and relative humidity. I investigated the influence of elevation and insulation coverage (presence of leaves vs. no leaves) on A. americanum (Lone star tick), H. longicornis (Asian longhorned tick), and A. maculatum (Gulf Coast tick). Elevation and insulation coverage had no significant impact on the overwintering survival of the Lone star and Asian longhorned ticks. Tick survival was mainly dictated by what life-stage they were in; Lone star ticks survived better as adult than at other life stages. Asian longhorned ticks survived better as nymphs than larva and adults. Insulation coverage influenced the overwintering survival of the Gulf Coast tick. These ticks survived better with no leaves, which may be associated with their preference of drier climates.

Em relação à fauna Culicidae, a Caatinga é um dos biomas mais desconhecidos do Brasil. Há carência de registro de ocorrência de culicídeos, bem como de estudos sobre as interações deles com o ambiente silvestre. Assim, o objetivo deste estudo foi investigar biodiversidade e aspectos ecológicos e epidemiológicos da fauna Culicidae em áreas de conservação do bioma Caatinga. Para isso foram consideradas duas unidades de conservação da Caatinga e realizados 19 levantamentos entomológicos mensais e consecutivos. Foram realizadas coletas de formas imaturas de mosquitos em bromélias, ocos de árvore e criadouros de solo, além da coleta de mosquitos adultos de hábitos diurno, crepuscular e noturno. Ao todo, entre mosquitos adultos e imaturos associados a habitats fitotelmatas, foram coletados 11.456 culicídeos distribuídos em 28 espécies, das quais 11 eram desconhecidas para a ciência. A fauna de imaturos coletados em bromélias e ocos de árvore interferiu na composição da fauna de mosquitos adultos e houve variações na abundância e nos padrões de diversidade de acordo com fitofisionomia do ambiente. Temperatura e umidade foram os parâmetros ambientais mais fortemente associados à abundância de culicídeos. Foram registradas novas ocorrências de anofelinos, coletados em criadouros de solo, ampliando a distribuição das espécies para o semiárido brasileiro. Este é um estudo pioneiro acerca da biodiversidade da fauna Culicidae em áreas de conservação da Caatinga que apresenta uma rica e desconhecida fauna de culicídeos, inédita para a ciência. / Regarding Culicidae fauna, Caatinga is one of the most unknown biomes of Brazil. There are few records of mosquitoes occurrence, as well as studies on their interactions with the wild environment. Therefore, the aimof this study was to investigate the biodiversity, ecological and epidemiological aspects of Culicidae fauna in conservation areas of the Caatinga biome. Two protected areas were considered for the study and 19 entomological surveys were performed monthly. Immature forms of mosquitoes were collected in bromeliads, tree holes and ground pools, as well as collection of adult mosquitoes with day time, twilight and nocturnal habits. Between adults and immatures associated with phytotelmatas habits, a total of 11,456 mosquitoes were collected, distributed in 28 species, 11 of which were unknown to science. The immature fauna collected in bromeliads and tree holes interfered in the fauna composition of adults and there were variations in the abundance and diversity patterns according to the environment phytophysiognomy. Temperature and humidity were the most strongly environmental factors associated with the abundance of mosquitoes. New records of anophelines collected inground pools were registered, broadening the distribution of species in the Brazilian semiarid region. This is a pioneering study on the biodiversity of the Culicidae in the Caatinga conservation areas which presents a rich and unknown mosquitoes fauna, unprecedented for science

Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-06-21T18:25:20Z No. of bitstreams: 1 AntoniaSilva.pdf: 3060571 bytes, checksum: a7f2fb96a4ad01ab72950bd6a3cbffca (MD5) / Made available in DSpace on 2017-06-21T18:25:20Z (GMT). No. of bitstreams: 1 AntoniaSilva.pdf: 3060571 bytes, checksum: a7f2fb96a4ad01ab72950bd6a3cbffca (MD5) Previous issue date: 2016-06-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão (FAPEMA) / Fundação de Amparo à Pesquisa de Minas Gerais (FAPEMIG) / The Sandflies are insects diptera nematocera belonging to the Psychodidae family, very important for public health, because some species are vectors of etiological agents of leishmaniasis, endemic parasitic disease in the state of Maranhão and in Brazil. These vectors are frequently found in natural ecotopes, domestic animal shelters and human habitations. This research aimed to study the occurrence of sandflies in the urban and rural peridomiciliary environment of municipality of Caxias, Maranhão, in notification area of cases of cutaneous and visceral leishmaniasis, as well as the rate of natural infection by Leishmania and analysis of blood food source. This is a cross-sectional, exploratory, descriptive and field study, with a quantitative approach, performed from March 2013 to February 2015. The specimens were collected with CDC (Center for Disease Control) light traps type in 20 homes, 10 in urban area and 10 in rural area. Were collected 15,895 specimens belonging to 17 species, one of genus Brumptomyia and 16 of Lutzomyia. The most abundant species were Lu. longipalpis (90.26%) and Lu. whitmani (7.65%). In the urban area the abundance of sandflies was higher in rainy season, and in the rural area in the dry season. Lu. longipalpis and Lu. whitmani occurred in two seasons, most frequently in rainy and dry season, respectively. From a total of 3, 520 female, 982 samples were used for DNA and PCR-RFLP extraction for detecting the presence of Leishmania. The vector Lu. longipalpis was found infected by Le. infantum (3.0%); Le. shawi (0.3%); Le. mexicana (0.2%); Le. braziliensis (0.6%) and Le. guyanensis (0.6%) and with mixed infection Le. infantum/Le. braziliensis (0.6%). The specie Lu. whitmani was infected by Le. infantum/Le. braziliensis (4.0%) and Le. braziliensis (4.3%). Other species found infected include: Lu. trinidadensis with Le. infantum/Le. braziliensis and Lu. evandroi and Lu. termitophila with Le. braziliensis and Le. guyanensis respectively. Based on these results it is suggested adopting control measures by the public health authorities to contain a future epidemic of AVL in this area, which is also endemic to ACL. For detection of food source were captured 778 engorged females, 573 were positive for eight different types of domestic and wild animals: dog, man, chicken, ox, pig, horse, rodent and opossum; obtaining mixed reactions in eight different associations: dog/rodent, man/chicken, chicken/rodent, dog/chicken, horse/rodent, rodent/pig and man/opossum. The presence of sandflies species infected with different species of leishmanias and fed with blood of domestic animals and human justifies the occurrence of endemic form of visceral and cutaneous leishmaniasis in the municipality of Caxias. Based on these results it is suggested adoption of control measures by the public health authorities to contain a future epidemic of these diseases. / Os flebotomíneos são dípteros nematóceros, pertencentes à família Psychodidae, muito importantes para a saúde pública, pois algumas espécies são vetores dos agentes etiológicos das leishmanioses, doenças parasitárias endêmicas em todo o território brasileiro. Esses vetores são encontrados com frequência em ecótopos naturais, abrigos de animais domésticos e habitações humanas. A presente pesquisa teve como objetivo estudar a ocorrência de flebotomíneos no ambiente peridomiciliar urbano e rural do município de Caxias, Maranhão, em área de notificação de casos de leishmaniose tegumentar e visceral, bem como, a taxa de infecção natural por Leishmania e análise da fonte alimentar sanguínea. Trata-se de um estudo transversal, exploratório, descritivo e de campo, tendo uma abordagem quantitativa, realizado no período de março de 2013 a fevereiro de 2015. Os espécimes foram coletados com armadilhas luminosas do tipo CDC (Center for Disease Control) em 20 residências, 10 na zona urbana e 10 na zona rural. Foram coletados 15.892 espécimes pertencente a 17 espécies, sendo uma do gênero Brumptomyia e 16 do gênero Lutzomyia. As espécies mais abundantes foram Lu. longipalpis (90,26%) e Lu. whitmani (7,65%). Na zona urbana a abundância de flebotomíneos foi maior no período chuvoso, e na zona rural na estação seca. Lu. longipalpis e Lu. Whitmani ocorreram nas duas estações, com mais frequência na estação chuvosa e seca, respectivamente. Do total de 3.520 fêmeas, 982 exemplares foram utilizados para a extração de DNA e PCR-RFLP para detecção de presença de Leishmania. O vetor Lu. longipalpis foi encontrado infectado por Le. infantum (3,0%), Le. shawi (0,3%), Le. mexicana (0,2%), Le. braziliensis (0,6%) e Le. guyanensis (0,6%) e com infecção mista Le. infantum/Le. braziliensis (0,6%). A espécie Lu. whitmani estava infectada com Le. infantum/Le. braziliensis (4,0%) e Le. braziliensis (4,3%). Outras espécies encontradas infectadas incluem-se: Lu. trinidadensis com Le. infantum/Le. braziliensis; Lu. evandroi e Lu. termitophila com Le. braziliensis e, Le. guyanensis, respectivamente. Para detecção da fonte alimentar foram utilizadas 778 fêmeas ingurgitadas, 573 positivaram para oito tipos diferentes de animais domésticos e silvestres, sendo detectadas reações simples representadas por sange de: cão, homem, galinha, boi, porco, cavalo, roedor e gambá e as reações mistas foram representadas por sangue de: cão/roedor, roedor/homem, galinha/homem, galinha/roedor, cão/galinha, cavalo/roedor, roedor/porco e homem/gambá. A presença de espécies de flebotomíneos infectadas com diferentes espécies de leshmânias e alimentados com sangue de animais domésticos e humanos justifica a ocorrência de forma endêmicas das leishmanioses visceral e tegumentar no município de Caxias. Diante dos resultados obtidos sugere-se adoção de medidas de controle por parte das autoridades de saúde pública, de forma a conter uma futura epidemia dessas doenças.

Em relação à fauna Culicidae, a Caatinga é um dos biomas mais desconhecidos do Brasil. Há carência de registro de ocorrência de culicídeos, bem como de estudos sobre as interações deles com o ambiente silvestre. Assim, o objetivo deste estudo foi investigar biodiversidade e aspectos ecológicos e epidemiológicos da fauna Culicidae em áreas de conservação do bioma Caatinga. Para isso foram consideradas duas unidades de conservação da Caatinga e realizados 19 levantamentos entomológicos mensais e consecutivos. Foram realizadas coletas de formas imaturas de mosquitos em bromélias, ocos de árvore e criadouros de solo, além da coleta de mosquitos adultos de hábitos diurno, crepuscular e noturno. Ao todo, entre mosquitos adultos e imaturos associados a habitats fitotelmatas, foram coletados 11.456 culicídeos distribuídos em 28 espécies, das quais 11 eram desconhecidas para a ciência. A fauna de imaturos coletados em bromélias e ocos de árvore interferiu na composição da fauna de mosquitos adultos e houve variações na abundância e nos padrões de diversidade de acordo com fitofisionomia do ambiente. Temperatura e umidade foram os parâmetros ambientais mais fortemente associados à abundância de culicídeos. Foram registradas novas ocorrências de anofelinos, coletados em criadouros de solo, ampliando a distribuição das espécies para o semiárido brasileiro. Este é um estudo pioneiro acerca da biodiversidade da fauna Culicidae em áreas de conservação da Caatinga que apresenta uma rica e desconhecida fauna de culicídeos, inédita para a ciência. / Regarding Culicidae fauna, Caatinga is one of the most unknown biomes of Brazil. There are few records of mosquitoes occurrence, as well as studies on their interactions with the wild environment. Therefore, the aimof this study was to investigate the biodiversity, ecological and epidemiological aspects of Culicidae fauna in conservation areas of the Caatinga biome. Two protected areas were considered for the study and 19 entomological surveys were performed monthly. Immature forms of mosquitoes were collected in bromeliads, tree holes and ground pools, as well as collection of adult mosquitoes with day time, twilight and nocturnal habits. Between adults and immatures associated with phytotelmatas habits, a total of 11,456 mosquitoes were collected, distributed in 28 species, 11 of which were unknown to science. The immature fauna collected in bromeliads and tree holes interfered in the fauna composition of adults and there were variations in the abundance and diversity patterns according to the environment phytophysiognomy. Temperature and humidity were the most strongly environmental factors associated with the abundance of mosquitoes. New records of anophelines collected inground pools were registered, broadening the distribution of species in the Brazilian semiarid region. This is a pioneering study on the biodiversity of the Culicidae in the Caatinga conservation areas which presents a rich and unknown mosquitoes fauna, unprecedented for science

Abstract :Bluetongue (BT) is a vector-borne infectious disease primarily transmitted to even- toed ungulates by the bite of several Culicoides species. The global distribution of BT can be attributed to the ubiquity of its vectors and its rapid spread, likely to the enhancement of human activities (intensification of animal production, trans- port, changing habitat). During the last decades, BT established in Southern Europe and more recently emerged in Northern Europe, causing the death of millions of domestic ruminants. On the same time, a Belgian research project has been set up to develop remote-sensing tools to study the EPidemiology and Space-TIme dynamicS of infectious diseases (EPISTIS). In that general framework, this thesis aimed to study the space-time distribution of the main Culicoides vectors occurring in Italy and Belgium, at two different scales. Firstly, we aimed to clarify the role of several eco-climatic factors on the regional-scale distribution of C. imicola in time, based on weekly samplings achieved throughout Italy from 2001 to 2006 and to develop an easy-to-use and reproducible tool, which could be widely validated on the basis of former vector sampling and freely accessible remote-sensing data. Secondly, we aimed to investigate how Culicoides species were distributed in the fine-scale habitat encountered throughout the agro-ecological landscapes of Belgium, while recent studies have suggested that the landscapes configuration could explain the spatial distribution of BT. In the first part, we showed that an autoregressive model where the observed monthly growth rate is predicted by monthly temperature, allowed predicting >70% of the seasonal variability in C. imicola trap catches. The model predicted the seasonality, the altitudinal gradient, and the low populations’ activity taking place during the winter. Incorporating eco-climatic indices such as the Normalized Difference Vegetation Index into the model did not enhance its predictive power. In the second part, we quantified how Culicoides populations are spatially structured in the neighbourhood of farms, and demonstrated the unexpectedly high level of population found in forest. We also showed how four classes of land use could influence the relative abundances of Culicoides species in the agro-ecological landscapes of Belgium. Although in summer, BT vectors were abundant in each of the four classes investigated, their relative abundances varied strongly as a function of sex, species and environmental conditions, and we quantified these variations. Finally, we also presented a new method to quantify the interference between Onderstepoort light traps, and used it to measure their range of attraction for several of the most common BT vectors species in Northern Europe. The model developed on C. imicola in Italy provided enthusiastic perspectives regarding the regional-scale analyses of its distribution in time, although further improvements are nevertheless required in order to assess the broad scale ecology of BT vectors throughout Europe. Mapping the abundances of C. imicola in Sardinia high- lighted an important lack of reliability attributable to the many land use classes that are currently not sampled in the vector surveillance achieved across Europe. Together with the novelties presented in the second part and the recent findings establishing that BT could circulate among wild hosts in both epidemiological systems (i.e. in Southern and Northern Europe), we call for increasing epidemiological and entomo- logical studies at the interface between farms and the surrounding natural habitats. Last, depicting in time the landscape-scale findings for Northern Europe highlighted how dramatic could be the role played by intensive farming practices to maintain BT within the agro-ecological landscapes studied and to facilitate its circulation between them. Quantifying the amplitude of the risk of disease transmission linked to these practices would require a further complex modeling approach accounting simultaneously for the diel activity of hosts, mainly resulting from the farming activities, the diel activities of different vector species and the landscapes configuration found in contrasted agro-ecological systems.<p>Résumé :La fièvre catarrhale ovine (FCO), encore appelée maladie de la langue bleue, est une maladie infectieuse des ruminants transmise par la piqûre d’un vecteur de type moucheron appartenant au genre Culicoides (Diptera :Ceratopogonidae). L’ubiquité de ses vecteurs peut expliquer son succès d’installation à l’échelle globale. Par ailleurs, sa rapide expansion a été grandement facilitée par l’importante activité anthropique (élevage, transport, modification de l’habitat) et peut-être même par les changements climatiques globaux. La FCO a été récemment qualifiée de maladie infectieuse émergente en Europe du fait de (i) son récent établissement dans la région, bien au delà de son aire de répartition traditionnelle, (ii) de sa forte capacité de dispersion affectant chaque jour un nombre plus important d’hôtes et enfin (iii) de sa forte virulence. Après avoir détaillé les caractéristiques majeures des deux principaux foyers de FCO rencontrés en Europe depuis 1998, la présente thèse s’est plus particulièrement intéressée à l’étude de la distribution spatio-temporelle de ses principaux vecteurs dans le sud (partie 1) puis dans le nord (partie 2) de l’Europe, à différentes échelles. Dans la première partie, un modèle discret, spatialement et temporellement explicite, a été développé afin de mesurer l’influence de différents facteurs éco-climatiques sur la distribution de Culicoides imicola, principal vecteur de la FCO dans le Bassin Méditerranéen. Les profils mensuels de distribution rencontrés en Sardaigne durant 6 années consécutives ont ainsi pu être reconstitués, principalement sur base de la température. Une cartographie de l’abondance de C. imicola sur le territoire a permis de mettre à jour le manque d’information sur sa distribution en dehors des exploitations agricoles. Dans la deuxième partie du travail, nous nous sommes penchés sur la distribution spatiale des Culicoides tels qu’on peut les rencontrer au sein de différents paysages agro-écologiques de Belgique. Nous avons ainsi pu décrire la structure adoptée par les populations de Culicoides au voisinage des fermes ainsi que quantifier l’importante population présente dans les forêts avoisinantes. Nous avons par ailleurs montré l’influence de différentes catégories d’utilisation du sol sur l’abondance et la composition en espèces. Enfin, nous avons présenté une méthode permettant de quantifier l’interférence entre des pièges lumineux utilisés dans un même paysage pour échantillonner les populations, et l’avons utilisé afin de mesurer leur rayon d’attractivité sur les espèces vectrices les plus communément rencontrées dans le nord de l’Europe. En guise de conclusion générale et conjointement aux récentes découvertes de cas de FCO au sein de la faune sauvage européenne, nous appelons à réaliser un plus grand nombre d’études éco-épidémiologiques à l’interface entre exploitations agricoles et zones (semi-) naturelles avoisinantes. En outres, les résultats présentés dans la seconde partie ont été mis en relation avec le mode de fonctionnement journalier de nos exploitations agricoles. Nous avons ainsi pu déduire le rôle dramatique joué par les pratiques agricoles intensives dans le maintien du virus de la FCO au sein de nos paysages agro-écologiques, ainsi que dans sa circulation d’un paysage à l’autre. Un cadre de modélisation complexe permettant une analyse simultanée de l’activité nycthémérale des hôtes de la FCO et de ses vecteurs Culicoides en fonction de la configuration des paysages agro-écologiques est néanmoins requis afin de quantifier l’amplitude du risque de transmission de la FCO lié aux pratiques agricoles intensives. / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished