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Durant de nombreuses décennies, la faune phlébotomienne (Diptera, Psychodidae, Phlebotominae) Malgaches est demeurée très peu explorée. Deux Grassomyia avaient été signalés puis une espèce décrite sous le nom de Sergentomyia berentiensis. A partir des années 2000, la faune de Madagascar a révélé une richesse et une diversité non soupçonnées jusqu'alors avec la description de plusieurs espèces nouvelles et d'un sous-genre nouveau : Vattieromyia. Cette thèse est une contribution à la connaissance des Phlébotomes de Madagascar et des îles voisines des Seychelles et des Comores.Notre approche a été qualitative et non quantitative. Les phlébotomes collectés à Madagascar, aux Comores et aux Seychelles ont été étudiés morphologiquement puis, pour certains d'entre eux, par biologie moléculaire à diverses fins : associations mâles-femelles et systématique évolutive. Dans ce dernier cas, différents marqueurs ribosomiques, mitochondriaux et nucléaires ont été séquencés selon les problématiques.A Madagascar, les Phlebotomus forment un groupe monophylétique. Nous suggérons, sur des arguments morphologiques et moléculaires, de les individualiser dans un sous-genre nouveau étant donnée la mise en évidence de la paraphylie du sous-genre Anaphlebotomus dans lequel ont été classées les espèces malgaches.Nos travaux révèlent que P. fertei possède une aire de distribution qui couvre la presque totalité du pays. Les séquences de cytochrome b individualisent de nombreuses populations selon leurs origines géographiques mais nous n'avons pas pu individualiser ces populations sur le plan morphologique et morphométrique. Les séquences de l'ITS2 n'individualisent pas ces populations et nous critiquons l'utilisation du cytochrome b, et plus largement des marqueurs mitochondriaux, pour la systématique des Phlébotomes.En ce qui concerne les autres espèces de Phlebotomus, elles possèdent toutes une distribution étroite, réduite à leur lieu de capture. Nous avons décrit deux espèces nouvelles durant cette thèse : P. vaomalalae et P. vincenti. Les études moléculaires et morphologiques révèlent l'existence d'au moins trois espèces nouvelles : deux sympatriques à Andranoilovy (dont une espèce commune avec Berenty) et une à Ankililaoka.Enfin, nous proposons le rattachement de P. huberti au genre Sergentomyia. Cette espèce ne possède pas de soies mésanepisternales et le mâle que nous décrivons dans ce travail possède les caractères génitaux des Sergentomyia. De plus, nous décrivons sur une la seule femelle, une espèce nouvelle proche de S. huberti. Une étude moléculaire menée avec d'autres espèces supposées proches (appartenant au sous-genre Sintonius) nous conduit à proposer la création d'un nouveau sous-genre pour classer ces espèces malgaches.Nous analysons la paléobiogéographie des Phlébotomes de Madagascar et envisageons au moins deux épisodes de peuplement : l'un très ancien (environ 120 millions d'années), « africain » datant de la fragmentation du Gondwana et le second, plus récent (65 millions d'années), provenant d'Asie via un pont formé par le plateau des Seychelles.D'un point de vue épidémiologique, la recherche d'ADN leishmanien s'est révélée négative sur tous les phlébotomes testés.Dans l'archipel des Comores, aucun phlébotome n'avait été rapporté. Au cours de trois campagnes de piégeage menées en 2003, 2007 et 2011, nous rapportons la première mention de phlébotomes dans ces îles et décrivons deux taxons nouveaux S. pessoni et S. goodmani comorensis.Aux Seychelles, nous avons identifié S. clydei à Aldabra. Cette population possède des séquences mitochondriales très différentes des nombreuses populations continentales étudiées. L'origine du peuplement de cette île volcanique demeure mystérieuse, sans adéquation avec les données relatives à l'horloge moléculaire du cytochrome b dont nous doutons de la fiabilité. / During the last century, the Phlebotomine sand fly fauna (Diptera, Psychodidae, Phlebotominae) of Madagascar remained largely unexplored. Two Grassomyia were recorded and a species has been described as Sergentomyia berentiensis. From the 2000s, this fauna revealed a richness hitherto unsuspected: it included the description of several new species for Science and of a new subgenus (Vattieromyia). The present study is a contribution to the knowledge of Phlebotomine sand flies from Madagascar and the neighboring archipelagos of the Seychelles and the Comoros.The sand flies collected in Madagascar, the Comoros and the Seychelles were studied morphologically and, for some of them, by molecular biology in order to associate males with females and also to perform molecular systematics. Several molecular ribosomal, nuclear, and mitochondrial markers have been combined.In Madagascar, the Phlebotomus are grouped in a clade. Based on morphological characters and molecular studies, we suggest their individualization in a new subgenus because we show subgenus Anaphlebotomus where the Malagasy Phlebotomus were classified, is paraphyletic.P. fertei exhibits a wide distribution all over country. Sequences of cytochrome b individualize many populations linked to their geographical origins. However, it is not possible to individualize these populations based on morphological and morphometric characters. The sequences of ITS2 do not individualize these populations and we criticize the use of cytochrome b and other mitochondrial markers for the systematics of Phlebotomine sand flies.Regarding the other Malgaches Phlebotomus, all of them have a narrow distribution, reduced to their place of capture. We described two new species for Science: P. vaomalalae and P. vincenti. Moreover, molecular and morphological studies support the existence of at least three new species: two in sympatry in Andranoilovy (probably also recorded in Berenty) and one in Ankililaoka.Finally, we propose that P. huberti belongs to the genus Sergentomyia and not to the genus Phlebotomus. It does not have mesanepisternal setae and the male that we describe here exhibits Sergentomyia's genital characters. Moreover, we described on a female belonging to a new species close to S. huberti. We carried out a molecular study including continental species supposed closely related (belonging to the subgenus Sintonius). It individualizes the Malagasy specimens and consequently, considering their typical pharyngeal armature, we propose the creation of a new subgenus to classify them.We analyze the paleobiogeography of Malagasy sand flies. In agreement with generalized tracks, the settlement of Madagascar followed two routes at different times: one very old (about 120 million years ago), from "Africa" dating from the Gondwana fragmentation and the second, more recent (65 million years), from Asia using a bridge formed by the Seychelles plateau.From an epidemiological point of view, the search of Leishmania DNA was negative in all sandflies processed.In the Comoros Archipelago, no sand fly had been reported in the past. During three field works carried out in 2003, 2007 and 2011, we report the first record of sandflies in these islands and we describe two new taxa: S. pessoni and S. goodmani comorensis.In the Seychelles, we identified S. clydei in Aldabra. This population has mitochondrial sequences highly differing from those of many continental populations processed. The settlement of this volcanic island remains mysterious. They are not in agreement with molecular clock of cytochrome b sequences which seems of doubtful use.

O objetivo desse trabalho foi: identificar as espécies de flebotomíneos, estimar a taxa de infecção dos flebotomíneos, identificar os agentes etiológicos envolvidos na transmissão da LTA no município de Assis Brasil, Acre. Foi realizada a PCR para a identificação de espécies de Leishmania em amostras de flebotomíneos e biópsias humanas. Um total de 6.850 exemplares foram capturados pertencentes a 66 espécies de flebotomíneos. As espécies mais abundantes foram Lu. auraensis, Lu. davisi, Lu. choti e Lu. shawi. Trinta e dois pools foram positivos para a presença de DNA de Leishmania com uma prevalência mínima de infecção de 1,85% para Lu. davisi e de 2,05% para Lu. auraensis. As espécies de Leishmania detectadas foram: Le. (Viannia) guyanensis e Le. (V.) braziliensis. Além dessas, outras duas espécies de Leishmania foram encontradas a partir das biópsias de lesões: Le. (V.) shawi e Le. (Le.) amazonenses. A doença foi mais prevalente no sexo masculino e residente na zona rural. Esse é o primeiro registro de Le. (V.) shawi e Le. (L.) amazonenses no Acre. / The objectives of this study were: to identify phlebotominae species, to estimate infection rates of phlebotomines, to identify the etiological agents involved in ATL transmission in the municipality of Assis Brasil, Acre. The PCR was used to identify Leishmania species in phlebotomine and human biopsy samples. A total of 6,850 sandflies. comprising 66 species were captured. The most abundant species were Lu. auraensis, Lu. davisi, Lu. choti e Lu. shawi. Thirty-two pools tested positive for the presence of Leishmania DNA, with a minimum infection rate of 1.85% in Lu. davisi and 2.05% in Lu. auraensis. The Leishmania species were identified as Le. (Viannia) guyanensis and Le. (V.) braziliensis. In addition to these, two other Leishmania species were identified from lesion biopsies: Le. (V.) shawi and Le. (Le.) amazonenses. The disease was most common among males (81.6%) e and persons living in rural areas (75.7%). This is the first record of Le. (V.) shawi and Le. (Le.) amazonenses in Acre.

Anuros há muito tempo são conhecidos como portadores de tripanossomas em todo o mundo. Esses tripanossomas são transmitidos por sanguessugas e insetos hematófagos. Nenhum levantamento foi feito na América do Sul. A taxonomia tradicional resulta em identificações não confiáveis desses tripanossomas, a diversidade genética foi pouco investigada e o a filogenético é pouco conhecida. Neste estudo mostramos grande prevalência e marcada diversidade molecular e morfológica entre tripanossomas de várias espécies de anuros da Amazônia, Floresta Atlântica e Pantanal. O relacionamento filogenético inferido entre tripanossomas do Brasil, América do Norte, Europa e África revelou 5 clados de isolados de anuros. Um deles contem isolados de anuros e flebotomíneos, sugerindo que esses insetos possam ser vetores de tripanossomas de anuros. Em geral, os dados mostraram certo grau de associação entre clados de isolados e filogeografia de anuros e sugeriram que trocas de hospedeiros e adaptação ecológica desempenharam um papel importante na história evolutiva desses tripanossomas. / Amphibians of the order Anura have long been known to be infected with trypanosomes worldwide, infecting frogs and toads and transmitted by leeches and insects. No surveys were carried out in South American anurans. Traditional taxonomy renders unreliable identification of these trypanosomes, genetic diversity was poorly investigated and phylogenetic relationships are far from be understood. In this study, we showed high prevalence and marked morphological and molecular diversity among trypanosomes from several species from Amazonia, Atlantic Forest and Pantanal. Phylogenetic relationships inferred among trypanosomes from Brazil, North America, Europe and Africa disclosed 5 major clades of anuran isolates. One clade contains anuran and sand fly isolates, suggesting that these insects can be vectors of anuran trypanosomes. In general, data showed a certain degree of association between clades of isolates and anuran phylogeography and suggested that host switching and ecological fitting also play a role in the evolutionary history of these trypanosomes.

O objetivo desse trabalho foi: identificar as espécies de flebotomíneos, estimar a taxa de infecção dos flebotomíneos, identificar os agentes etiológicos envolvidos na transmissão da LTA no município de Assis Brasil, Acre. Foi realizada a PCR para a identificação de espécies de Leishmania em amostras de flebotomíneos e biópsias humanas. Um total de 6.850 exemplares foram capturados pertencentes a 66 espécies de flebotomíneos. As espécies mais abundantes foram Lu. auraensis, Lu. davisi, Lu. choti e Lu. shawi. Trinta e dois pools foram positivos para a presença de DNA de Leishmania com uma prevalência mínima de infecção de 1,85% para Lu. davisi e de 2,05% para Lu. auraensis. As espécies de Leishmania detectadas foram: Le. (Viannia) guyanensis e Le. (V.) braziliensis. Além dessas, outras duas espécies de Leishmania foram encontradas a partir das biópsias de lesões: Le. (V.) shawi e Le. (Le.) amazonenses. A doença foi mais prevalente no sexo masculino e residente na zona rural. Esse é o primeiro registro de Le. (V.) shawi e Le. (L.) amazonenses no Acre. / The objectives of this study were: to identify phlebotominae species, to estimate infection rates of phlebotomines, to identify the etiological agents involved in ATL transmission in the municipality of Assis Brasil, Acre. The PCR was used to identify Leishmania species in phlebotomine and human biopsy samples. A total of 6,850 sandflies. comprising 66 species were captured. The most abundant species were Lu. auraensis, Lu. davisi, Lu. choti e Lu. shawi. Thirty-two pools tested positive for the presence of Leishmania DNA, with a minimum infection rate of 1.85% in Lu. davisi and 2.05% in Lu. auraensis. The Leishmania species were identified as Le. (Viannia) guyanensis and Le. (V.) braziliensis. In addition to these, two other Leishmania species were identified from lesion biopsies: Le. (V.) shawi and Le. (Le.) amazonenses. The disease was most common among males (81.6%) e and persons living in rural areas (75.7%). This is the first record of Le. (V.) shawi and Le. (Le.) amazonenses in Acre.

Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-09-13T13:48:58Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) amanda_oliveira_baracho.pdf: 1018229 bytes, checksum: 7da405c92d90a6056df94d878fc77113 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-10-02T16:26:57Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) amanda_oliveira_baracho.pdf: 1018229 bytes, checksum: 7da405c92d90a6056df94d878fc77113 (MD5) / Made available in DSpace on 2018-10-02T16:27:10Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) amanda_oliveira_baracho.pdf: 1018229 bytes, checksum: 7da405c92d90a6056df94d878fc77113 (MD5) Previous issue date: 2018 / Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) / A leishmaniose visceral ? uma doen?a parasit?ria de transmiss?o vetorial causada por protozo?rios do g?nero Leishmania, com elevado grau de letalidade e que atinge milh?es de pessoas no mundo. A busca por produtos alternativos para a elimina??o do vetor tem como objetivo minimizar os impactos causados pelos inseticidas qu?micos sint?ticos utilizados pelos programas de controle, sendo cada vez mais frequente a pesquisa em produtos de origem bot?nica com atividade inseticida. Organismos vegetais s?o capazes de produzir compostos org?nicos de comprovada toxicidade frente aos insetos e, diante disto, avaliou-se neste trabalho a atividade inseticida de extratos de Caryocar brasiliense, planta nativa do Cerrado popularmente conhecida como ?pequi?, sobre flebotom?neos da esp?cie Lutzomyia longipalpis, principal transmissora da leishmaniose visceral. Extratos hidroetan?licos, etan?licos e ciclohex?nicos de folhas e cascas de C. brasiliense foram preparados e dilu?dos em solu??o de Tween 80 a 3% para a obten??o de concentra??es a 50, 100, 200 e 400 mg.mL-1, para a realiza??o dos ensaios biol?gicos. Os flebotom?neos foram coletados em uma localidade rural do munic?pio de Diamantina/MG. Um n?mero amostral de 30 flebotom?neos foi posto em contato com os extratos e a mortalidade foi avaliada ap?s 1, 2, 4, 16, 24 48 e 72 horas de exposi??o, bem como grupos controle negativos (?gua destilada e Tween) e positivo (cipermetrina). A identifica??o dos constituintes qu?micos dos extratos tamb?m foi avaliada. Ap?s 72h de experimento, foram registradas mortalidades de 93,3% pelo extrato hidroetan?lico da casca a 400 mg.mL-1, 66,3% pelo etan?lico da casca a 50 mg.mL-1 e 81,1% pelo ciclohex?nico de folhas a 200 mg.mL-1. Os extratos hidroetan?licos da casca mostraram-se estatisticamente semelhantes ? a??o da cipermetrina em 72h de experimento, indicando que este extrato foi o mais eficiente quanto ? atividade inseticida. Foram identificados triterpenos, esteroides, taninos, flavonoides, alcaloides e saponinas nos extratos. Os resultados obtidos sugerem que os extratos hidroetan?licos de C. brasiliense, sobretudo das cascas, s?o promissores na busca por compostos naturais com atividade inseticida sobre Lu. longipalpis. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biologia Animal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2018. / Visceral leishmaniasis is a vector-borne disease caused by a protozoan of the genus Leishmania with high lethality rate that reaches millions of people worldwide. The impacts caused by synthetic insecticides used in control programs are well known. In this context, research on alternative products for vector control, especially products of botanical origin, has been frequent in order to minimize the impacts of synthetic ones. Plants are capable to produce organic compounds with insect toxicity. Here, the insecticidal activity of Caryocar brasiliense extracts, a native plant of Brazilian savannah, popularly known as "pequi", on Lutzomyia longipalpis, the main vector of visceral leishmaniasis, was tested. Hydroethanolic, ethanolic and cyclohexanic extracts of leaves and barks of C. brasiliense were prepared and diluted in Tween 80 (3%) to obtain concentrations of 50, 100, 200 and 400 mg.mL-1 for the biological tests. Phlebotomine sandflies were collected in a rural locality of Diamantina (Minas Gerais state, Brazil). Thirty sand flies were exposed to the extracts and mortality was evaluated after 1, 2, 4, 16, 24 48 and 72 hours of exposure, as well as negative control groups (distilled water and Tween) and positive (cypermethrin). Chemical compounds of the extracts were also evaluated. Mortalities rates of 93.3% were observed for the hydroethanolic extract of the bark at 400 mg.mL-1, 66.3% for the ethanolic bark at 50 mg.mL-1 and 81.1% for the cyclohexane of leaves at 200 mg.mL-1. The hydroethanolic extracts of the bark showed to be statistically similar to the action of cypermethrin in 72h of the experiment, indicating that this extract was the most efficient as an insecticide. Triterpenes, steroids, tannins, flavonoids, alkaloids and saponins were identified in the extracts. The results obtained suggest that the hydroethanolic extracts of C. brasiliense, especially of the bark, are promising for the use of natural compounds to control Lu. longipalpis.

Anuros há muito tempo são conhecidos como portadores de tripanossomas em todo o mundo. Esses tripanossomas são transmitidos por sanguessugas e insetos hematófagos. Nenhum levantamento foi feito na América do Sul. A taxonomia tradicional resulta em identificações não confiáveis desses tripanossomas, a diversidade genética foi pouco investigada e o a filogenético é pouco conhecida. Neste estudo mostramos grande prevalência e marcada diversidade molecular e morfológica entre tripanossomas de várias espécies de anuros da Amazônia, Floresta Atlântica e Pantanal. O relacionamento filogenético inferido entre tripanossomas do Brasil, América do Norte, Europa e África revelou 5 clados de isolados de anuros. Um deles contem isolados de anuros e flebotomíneos, sugerindo que esses insetos possam ser vetores de tripanossomas de anuros. Em geral, os dados mostraram certo grau de associação entre clados de isolados e filogeografia de anuros e sugeriram que trocas de hospedeiros e adaptação ecológica desempenharam um papel importante na história evolutiva desses tripanossomas. / Amphibians of the order Anura have long been known to be infected with trypanosomes worldwide, infecting frogs and toads and transmitted by leeches and insects. No surveys were carried out in South American anurans. Traditional taxonomy renders unreliable identification of these trypanosomes, genetic diversity was poorly investigated and phylogenetic relationships are far from be understood. In this study, we showed high prevalence and marked morphological and molecular diversity among trypanosomes from several species from Amazonia, Atlantic Forest and Pantanal. Phylogenetic relationships inferred among trypanosomes from Brazil, North America, Europe and Africa disclosed 5 major clades of anuran isolates. One clade contains anuran and sand fly isolates, suggesting that these insects can be vectors of anuran trypanosomes. In general, data showed a certain degree of association between clades of isolates and anuran phylogeography and suggested that host switching and ecological fitting also play a role in the evolutionary history of these trypanosomes.

Made available in DSpace on 2016-04-28T20:16:24Z (GMT). No. of bitstreams: 1 2007- Patricia Giupponi Cardoso.pdf: 1457957 bytes, checksum: 77491851c890766bcc83bde133994ac6 (MD5) Previous issue date: 2007-10-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The American Cutaneous Leishmaniasis (ACL) is a no contagious infectious illness caused by Leishmania protozoa genera affecting skin and mucous membranes basically being a zoonotic infection. The aim of this study was to cany out phlebotominic fauna survey in ACL human cases occurrence areas. For sandfly collection monthly systematic captures by Castro trap from 6 o clock p.m. to 10 o clock p.m. for 12 months were performed. The diptera were placed on 70% alcohol bottles and carried to Sergio Arouca Public Health National School Biological Sciences Department Vectors Laboratory, Oswaldo Cruz Foundation, Rio de Janeiro, where they have been clarified and identified, as well. For dogs serology, blood samples from invaded residences animals as well as from a neighbour one, by venous puncture were taken. After serum centrifugation and separation, samples were stored at 20?C till serological assays performance at FIOCRUZ Public Health Nation School Immunodiagnosis Laboratory. The following methods: Indirect Immunofluorescence Reaction (IFIR) and Enzyme-linked immunosorbent assay (ELISA) were used. From October, 2004 to September, 2005, 2390 units from four species were captured. The predominant species was the Lutzomyia intermedia with 97.1% from total collected, followed by L. whitmani 1.6%, L.migonei 1.21% and L.oswaldoi 0.09 %. From 35 dogs serology: 60% (21) no reagent animals were reported, 22.9% just for ELISA, 2.9% for IFIR, and 14.2% (5) reagent animals for both techniques, definitely positive. No correlated evidences between serologies (IFIR+/ELISA+ and other results) in regard to animals residence (ill or neighbour) by Fisher statistical test were reported. It might be suggested that ACL transmission in Serop?dica County has basically been spread by Lutzomyia intermedia specie. The presence of reagent dogs unless suggestive injury may contribute for new ACL reports. / A Leishmaniose Tegumentar Americana (LTA) ? uma doen?a infecciosa n?o contagiosa causada por protozo?rios do g?nero Leishmania que acomete a pele e mucosa, sendo primariamente uma infec??o zoon?tica. O objetivo desta pesquisa foi realizar o levantamento da fauna flebotom?nica em ?reas com ocorr?ncia de casos humanos de LTA. Para coleta dos fleb?tomos foram realizadas capturas mensais sistem?ticas utilizando o capturador de Castro, no hor?rio das 18 ?s 22h, durante 12 meses. Os d?pteros foram colocados em frascos contendo ?lcool 70% e transportados para o laborat?rio de Vetores do Departamento de Ci?ncias Biol?gicas da Escola Nacional de Sa?de P?blica S?rgio Arouca, Funda??o Oswaldo Cruz, RJ, onde foram clarificados e identificados. Para sorologia dos c?es, amostras de sangue foram coletadas por venopun??o em animais residentes nos domic?lios acometidos e de c?es vizinhos. Ap?s centrifuga??o e separa??o do soro, as amostras foram conservadas a -20?C, at? o momento da realiza??o dos ensaios sorol?gicos no laborat?rio de Imudiagn?stico da ENSP, da FIOCRUZ. Empregaram-se os seguintes m?todos: Rea??o de Imunofluoresc?ncia Indireta (RIFI) e o enzyme-linked immunosorbent assay (ELISA). Foram capturados 2390 exemplares de flebotom?neos entre os meses de outubro de 2004 a setembro de 2005, pertencentes a quatro esp?cies. A esp?cie predominante foi a Lutzomyia intermedia com 97,1% do total coletado, seguida pela L. whitmani 1,6% , L.migonei 1,21% e L.oswaldoi 0,09 %. Da sorologia de 35 c?es: 60% (21) animais foram considerados n?o reativos; 22,9% reativos somente para ELISA; 2,9% somente RIFI e 14,2% (5) dos c?es reativos para as duas t?cnicas, conclusivamente positivos. N?o houve evid?ncias de associa??o entre sorologia (RIFI+/ELISA+ e outros resultados) com a propriedade do animal (paciente ou vizinho), segundo o teste exato de Fisher. Aparentemente a transmiss?o da LTA no munic?pio de Serop?dica esteja sendo veiculada pela L. intermedia. A presen?a de c?es reativos sem a exist?ncia de les?o sugestiva pode contribir para novos focos da LTA, funcionando como um animal em potencial para manuten??o da protozoose.

Les phlébotomes sont les vecteurs reconnus de plusieurs arbovirus, en particulier du genre Phlebovirus, ainsi que de parasites du genre Leishmania. Les infections par les phlébovirus sont responsables chez l’homme de maladies décrites depuis longtemps, pourtant ils demeurent méconnus, avec en particulier un manque de données épidémiologiques et d’outils de diagnostic.Dans une première partie, des études de séroprévalence nous ont permis d’aborder l’impact en santé publique, dans le sud-est de la France, de deux phlébovirus connus pour leur pouvoir pathogène chez l’homme, Toscana virus (TOSV) et Sandfly fever Sicilian virus (SFSV). Pour ce dernier, des anticorps spécifiques (IgG) ont été détectés dans moins de 1% des sérums testés, ce qui suggère que SFSV joue un rôle mineur dans les pathologies humaines de cette région ; ces résultats sont corroborés par l’absence, durant ces dernières décennies, de cas documentés d’infection aigüe due à SFSV en Europe occidentale. Nous avons donc pu concentrer notre travail sur le deuxième groupe de phlébovirus d’intérêt chez l’homme, le groupe des Sandfly fever Naples virus, qui inclut notamment TOSV. Nous avons démontré l’existence d’un lien épidémiologique entre les infections à Leishmania infantum et celles à TOSV, certainement dû au fait que ces pathogènes sont transmis par un vecteur commun (Phlebotomus perniciosus). Les analyses statistiques ont montré que les personnes exposées aux infections à TOSV ont plus de chance d’être aussi infectées par les parasites leishmanies (et vice versa). En admettant que ce lien épidémiologique entre leishmanioses et infections à TOSV est représenté par l’exposition à la piqûre d’un vecteur commun, cette étude confirme l’implication de Phlebotomus perniciosus en tant que vecteur principal de TOSV dans le sud de la France. Cette étude suggère également que certaines données épidémiologiques disponibles pour la leishmaniose pourraient être utilisées pour décrypter l’épidémiologie des infections à TOSV.La deuxième partie de cette thèse est consacrée à la détection, l’isolement et la caractérisation de virus, déjà connus ou inconnus, dans les populations de phlébotomes en France et en Afrique du Nord. Pour atteindre cet objectif, nous avons dû développer une plateforme d’analyse à au débit, adaptée pour la découverte de virus dans les phlébotomes, qui permette de traiter un grand nombre d’échantillons à faible coût. Cette plateforme a récemment été complétée par un outil de Next Generation Sequencing, afin de réaliser la caractérisation génétique complète des virus isolés et découverts. Au total, 12 576 phlébotomes ont été capturés au cours de 12 campagnes de capture menées en France, en Tunisie et en Algérie. Au sein d’une même zone géographique, la découverte de plusieurs nouveaux phlébovirus, ainsi que leur taux d’infection observé dans les populations de phlébotomes, ont démontré que la diversité de phlebovirus est bien plus importante qu’attendue.Dans la troisième partie de cette thèse, une étude de séroprévalence a été menée sur des sérums humains en utilisant des tests comparatifs de neutralisation de virus. Cette étude nous a permis d’exclure le virus Punique, récemment découvert, de la liste des principales menaces en santé publique au nord de la Tunisie, et de confirmer que TOSV est le principal phlebovirus pathogène ayant un impact en santé publique dans cette région du pays. Cette méthode de neutralisation est capable d’identifier précisément, parmi des virus génétiquement proches, le virus contre lequel les anticorps présents dans le sang ont été produits, ce qui permet de déterminer la capacité de chacun de ces virus à jouer un rôle en santé publique. / Sandflies are vectors of various arthropod-borne viruses, in particular viruses within the genus Phlebovirus, family Bunyaviridae, and of parasites in the genus Leishmania. Human diseases caused by infection with sandfly-borne phleboviruses are known for a long time, but they remain neglected due to the lack of epidemiological knowledge and of diagnostic tools.The first part consisted of seroprevalence studies in human sera to address the public health impact in south-eastern France of two recognized sandfly-borne phleboviruses, namely Toscana virus (TOSV) and Sandfly fever Sicilian virus (SFSV). Concerning the latter, specific IgG were detected in less than 1% of tested sera, suggesting that SFSV play a minor role in human disease in the region; this finding was corroborated with the lack of documented case of acute infection due to SFSV in Western Europe during the last decade. This pleaded for focusing on the other group of sandfly fever viruses known for their human interest, namely the group of Sandfly fever Naples virus that includes TOSV. We demonstrated an existing epidemiological relationship between Leishmania infantum and TOSV infections, presumably through the transmission by the common arthropod vector (Phlebotomus perniciosus). Statistical analysis showed that persons exposed to TOSV infection are at greater risk of being infected with Leishmania parasite (and vice versa). Assuming that epidemiological link between leishmaniasis and TOSV infection may be represented by the exposure to the bite of a common vector, this study confirms the involvement of Phlebotomus perniciosus as the major vector of TOSV in the South of France. This study also suggests that some of the epidemiological data available on Leishmaniasis may be used to decipher the epidemiology of TOSV infections..The second part of this thesis was dedicated to detection, isolation and characterization of existing and/or new phleboviruses in sandfly populations in France and in North Africa. To achieve this aim, we had to set up a high-throughput cost-effective platform amenable to virus discovery in sandflies; this sandfly-processing platform has been recently docked to a Next Generation Sequencing platform for full genetic characterization of newly isolated and discovered viruses. A total of 12,576 sandflies were trapped during 12 campaigns conducted in France, Tunisia and Algeria. The discovery of several new phleboviruses and their observed frequency in sandfly populations has clearly demonstrated that within a given geographic area, virus diversity is much higher than previously believed.In the third part of this thesis, a seroprevalence study based on comparative virus neutralization tests was performed on human sera and allowed to exclude the newly described Punique virus from the list of major public health threats in northern Tunisia, and to confirm that TOSV is the dominant phleboviral pathogen with an impact on public health in this part of the country. This neutralization method is suitable to identify precisely the virus against which antibodues were elicited, allowing to discriminate among closely related phleboviruses, and to determine their propensity to play a role in public health.

Leishmaniasis is a infect parasitic disease complex with a zoonotic character and vetorial trasmition caused by different morfologic species similar to flagellated protozoa of the Leishmania genus. They represent a serious problem of public health with cases registered on almost all the continents. Despite the existence of drugs with effective action on the parasitics, nearly two million new cases of distints clinic form happen every year and 350 million people are under risk of contracting the disease. As the interest of the pharmaceutical industry in this problem is small because of the reduced potential of lucrative return, once the reached population has a low income, the leishmaniasis is part of the group of the neglected diseases. In addition, it is believed that the environmental transformations and the man's intense migratory process to peripheries of the cities under inadequate conditions of habitation and improvement caused changes in the transmission way of the disease, causing the expansion of the endemic areas and the existence of new focus in urban areas of municipalities of medium and big load. In Uberlândia studies demonstrated that the construction of hydroelectric power station produced ecological modifications and they interfered in the biological communities, like the prevalence of the vectors in the peridomicile area. The general objective of this work was the research around the transmission of leishmaniasis in Uberlândia - MG and had as specific objectives the study of the sandfly fauna, the environmental conditions related to the presence of the Lutzomyia longipalpis, to describe the profile seroepidemiologic of the canine population and to relate the occurrence of the visceral leishmaniase in Uberlândia with the environmental alterations. In the period of february of 2005 to december of 2007 systematized monthly collections were accomplished, using luminous traps models CDC and, in the peridomicile areas of residences closed to the woods, the trap of the type hut of Shannon was used, in 17 places to Araguaia river s margins near of Miranda's hydroelectric power station and Amador Aguiar Naves I and II. They were collected 1.695 phlebotomine sand flies specimens belonging to 16 species. The species of importance epidemic more prevalent were Lutzomyia whitmani (31%) and L. longipalpis (13,3%), reaching up to 44,3% of the total collected specimens. Inquiries canine were accomplished in animals of both sexes and the same or superior age to three months, residents in places of the study area where specimens of L. longipalpis were captured. During the study period 747 dogs were tested and no one showed acting result for the disease. Of the ecological factors analyzed in the study area, the presence of animal shelters in the peridomicile areas of the analyzed residences showed strong influence in the domiciliation of the L. longipalpis and they point for the domiciliation of L. whitmani. Our studies demonstrated although the occurrence of the first case human of human visceral leishmaniase in Uberlândia didn't proceed to the cases of canine leishmaniase. Now the leishmaniase already constitutes a problem of public health in the municipality and the epidemic study is decisive factor for the effective planning of strategies for the control of the disease. / As leishmanioses são um complexo de doenças infecto-parasitárias, de caráter zoonótico e transmissão vetorial, causadas por diferentes espécies morfologicamente semelhantes de protozoários flagelados do gênero Leishmania. Constituem um importante problema de saúde pública, com registro de casos em quase todos os continentes. Embora existam drogas com ação eficaz sobre os parasitos, aproximadamente dois milhões de novos casos de diferentes formas clínicas ocorrem a cada ano e 350 milhões de pessoas se encontram sob risco de contrair a enfermidade. Como o interesse da indústria farmacêutica nesse tema é pequeno, pelo reduzido potencial de retorno lucrativo, uma vez que a população atingida é de baixa renda, as leishmanioses fazem parte do grupo das doenças negligenciadas. Em adição, acredita-se que as transformações ambientais e o intenso processo migratório do homem para as periferias das cidades sob condições inadequadas de habitação e saneamento provocaram mudanças no padrão de transmissão da doença, acarretando a expansão das áreas endêmicas e o aparecimento de novos focos em áreas urbanas de municípios de médio e grande porte. Em Uberlândia, estudos demonstraram que a construção de usinas hidrelétricas produziram modificações ecológicas e interferiram nas comunidades biológicas, dentre estas, a prevalência dos vetores nos peridomicílios. O objetivo geral deste trabalho foi estudar a transmissão de Leishmanioses em Uberlândia MG e teve como objetivos específicos estudar a fauna flebotomínica, estudar as condições ambientais relacionadas à presença do Lutzomyia longipalpis, descrever o perfil soroepidemiológico da população canina e relacionar a ocorrência da leishmaniose visceral em Uberlândia com as alterações ambientais. No período de fevereiro de 2005 a dezembro de 2007 coletas mensais sistematizadas foram realizadas, utilizando armadilhas luminosas modelo CDC e, no peridomicílio de residências localizadas muito próximas da mata, foi utilizada a armadilha do tipo barraca de Shannon, em 17 localidades às margens do Rio Araguari, próximas às UHE de Miranda e Amador Aguiar Naves I e II. Foram coletados 1.695 espécimes de flebotomíneos pertencentes a 16 espécies. As espécies de importância epidemiológica mais prevalentes foram Lutzomyia whitmani (31%) e L. longipalpis (13,3%), perfazendo juntas 44,3% do total de espécimes coletados. Foram realizados inquéritos caninos censitários em animais de ambos os sexos e idade igual ou superior a três meses, residentes em localidades da área de estudo onde foram capturados exemplares de L. longipalpis. Durante o período de estudo foram testados 747 cães e nenhum animal apresentou resultado reagente para a doença. Dos fatores ecológicos analisados na área de estudo, a presença de abrigos de animais no peridomicílio das residências analisadas mostrou forte influência na domiciliação do L. longipalpis e apontam para a domiciliação de L. whitmani. Nossos estudos demonstraram ainda que a ocorrência do primeiro caso humano de leishmaniose visceral humana em Uberlândia não precedeu ao de casos de leishmaniose canina. Atualmente a leishmaniose já constitui um problema de saúde pública no município e, o estudo epidemiológico é fator decisivo para o planejamento efetivo de estratégias para o controle da doença. / Doutor em Geografia