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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.
1

Caracterización de un nuevo flavivirus aislado de Culex (melanoconion) ocossa de Iquitos, Perú

Evangelista Villavicencio, Julio Antonio January 2016 (has links)
Describe el aislamiento y caracterización molecular de un nuevo flavivirus únicamente de mosquito, aislado de Culex (Melanoconion) occossa colectados en 2009 de un área urbana de Iquitos, Perú, ubicada en la cuenca del Amazonas, en la región noreste del Perú. La evidencia del Flavivirus es detectada mediante ensayo de inmunofluorescencia indirecta (IFI) en sobrenadante de cultivo celular de las células infectadas C6/36 usando anticuerpos policlonales grupo de Flavivirus y confirmada por RT-PCR. En comparación por pares de las secuencias de la región ENV, la más alta de nucleótidos (47,4%) y de aminoácidos (39,8%) la identidad se observa en el virus Nounané (NOUV). En comparación por pares de la región NS5, la identidad de nucleótidos más alta se observa en el virus Spondweni (65,9%), el virus de Iguape (IGUV; 65,7%) y el virus de Kedougou (65,6%); sin embargo, en el nivel de aminoácidos, la más alta identidad en pares de bases se observa en IGUV (69,8%), virus Naranjal (69,6%) y el virus Bussuquara (69,3%). El análisis filogenético utilizando ENV parcial y secuencias de aminoácidos NS5 revela que este Flavivirus forma un clado con NOUV. Para investigar la gama de huéspedes del nuevo Flavivirus, se inoculan una variedad de células de mamíferos (Vero 76, Vero E6, BHK, LLCMK y MDCK) con el tercer pasaje del aislamiento C6/36 y monitorea el efecto citopático (EC). No se detecta EC, y todas las líneas de células de mamífero son negativas para el antígeno Flavivirus por IFI y ARN Flavivirus por RT-PCR luego de catorce días de incubación. Propone que este Flavivirus genéticamente diferente sea llamado Nanay Virus (NANV), debido a la zona de Iquitos, Perú, donde fue detectado por primera vez.
2

Estudo Fitoquímico do Óleo Essencial dos Frutos da Aroeira (Schinus terebinthifolius RADDI) e Sua Eficácia no Combate ao Dengue

COLE, E. R. 07 March 2008 (has links)
Made available in DSpace on 2016-08-29T15:35:20Z (GMT). No. of bitstreams: 1 tese_2440_Eduardo Roberto Cole.pdf: 824296 bytes, checksum: 4e07ddc64143283e79dda5885925fe74 (MD5) Previous issue date: 2008-03-07 / O dengue é considerado a mais importante das arboviroses humanas, constituindo atualmente um dos principais problemas de Saúde Pública no mundo. A doença é causada por um vírus do gênero Flavivirus, com quatro diferentes sorotipos, transmitidos por mosquitos do gênero Aedes, sendo o Aedes aegypti seu principal vetor. O controle do vetor por meio de inseticidas sintéticos figura como a principal medida adotada no combate a doença, uma vez que não existem vacinas efetivas contra os diferentes sorotipos do vírus. Os inseticidas, apesar de eficazes, apresentam sérios problemas relacionados ao seu uso, dentre os quais podem ser destacados os danos ambientais, a toxicidade para uso humano e o risco de desenvolvimento de larvas e adultos resistentes.
3

Design and Evaluation of a Non-Structural Protein 1-Based Diagnostic Zika Virus Infection

January 2020 (has links)
archives@tulane.edu / Zika virus (ZIKV), a member of the Flaviviridae family, was the cause of a large viral outbreak reaching across the Americas during 2015 and 2016. Discovered in 1947, it has historically been a neglected disease, due to its emergence in humans on a large scale being recent. At the time of the outbreak, no FDA approved ZIKV diagnostics existed, and those that were able to detect the virus were unable to distinguish it from related viruses such as Dengue virus (DENV), and at this time, no approved therapeutics or vaccines are available. We investigated the ability of diagnostics targeted toward both anti-NS1 antibodies and NS1 antigen circulating during infection to detect current or past ZIKV disease, as well as the capability of NS1 to produce a protective response. Our studies suggest anti-NS1diagnostics are feasible, though some populations may display an immune response reminiscent of a prior infection. Levels of circulating NS1 were lower than those produced during DENV infection, though were still detectable with our assay. Additionally, intraperitoneal immunization with NS1 produced an anti-ZIKV NS1 response that coincided with a decrease in viremia, though further work was needed to discern life-prolonging effects. Together, this work furthers the development of the tools necessary to combat future outbreaks of ZIKV in vulnerable populations. / 1 / Brandon Beddingfield
4

Impact of West Nile virus on the natural history of St. Louis encephalitis virus in Florida

Ottendorfer, Christy L. January 2008 (has links)
Dissertation (Ph.D.)--University of South Florida, 2008. / Title from PDF of title page. Document formatted into pages; contains 719 pages. Includes vita. Includes bibliographical references.
5

Génomique des Flavivirus : Contribution à l'analyse taxonomique et phylogénique

Moureau, Grégory 17 January 2012 (has links)
Les virus à ARN - à l'exception des rétrovirus - représentent plus de 200 pathogènes humains et/ou vétérinaires majeurs. Ils sont pour la plupart considérés comme émergents, durant les dernières années ils ont été retrouvés au-delà de leur territoire d'origine, dans de nouvelles régions du monde. Les plus connus de ces virus sont le virus du West Nile, le virus chikungunya, la grippe, le coronavirus SRAS, l'entérovirus 71 (agent responsable de la fièvre aphteuse), les virus de la dengue, l'hépatite C virus, le virus de la fièvre hémorragique de Crimée Congo, le virus de la vallée du Rift, l'encéphalite japonaise et plusieurs entérovirus humains. En terme de mortalité et morbidité ils sont à l'origine de plus 100 millions de cas par an et la menace a tendance à augmenter. Ces statistiques sont démoralisantes quand on considère les immenses progrès de la médecine et de la science durant ces dernières dizaines d'années. Les recherches présentées dans ma thèse portent sur le genre Flavivirus, au sein duquel on retrouve le virus de la fièvre jaune, un pathogène humain responsable d'épidémies majeures en Afrique et en Amérique latine durant les 300 à 400 dernières années. Ce virus est toujours responsable d'épidémies majeures en Afrique malgré un vaccin très bien toléré et des plus efficaces. On assiste au même scénario avec le virus de l'encéphalite japonaise en Inde. / Without including the retroviruses, there are in excess of 200 RNA viruses that are recognised human and/or animal pathogens, many of which are considered to be emerging viruses because during recent years they have dispersed beyond their original territories causing epidemics in new regions of the World. The more well known of these emerging viruses include, West Nile virus, chikungunya virus, influenza virus, SARS coronavirus, EV71 virus (the aetiological agent of hand foot and mouth disease), dengue virus, hepatitis C virus, Crimean Congo haemorrhagic fever virus, Rift Valley fever virus, Japanese encephalitis virus and many human enteroviruses from a variety of genera. The combined global morbidity and mortality figures for these viruses add up to 100s of millions per year and the current trend appears to be upwards. This is a depressing statistic when one considers the amazing medical and scientific achievements that we have witnessed during the past decades. The studies described in my thesis were focused on the genus Flavivirus the type species of which is yellow fever virus, another terrifyingly virulent human pathogen that has caused so much suffering in Africa and Latin America during the past 300 to 400 years. This virus continues to cause major epidemics in Africa despite the availability of one of the safest and most effective vaccines with which to control infections due to yellow fever virus. Indeed similar comments can be made in the context of the flavivirus Japanese encephalitis virus in India.
6

Pesquisa de infecções por Flavivírus da encefalite de Saint Louis, Rocio e Oeste do Nilo em cavalos, por inquérito sorológico e isolamento viral / Searching for Saint Louis Encephalitis, Rocio and West Nile Flavivirus infections in horses.

Jaqueline Raymondi Silva 05 July 2010 (has links)
Arboviroses são grave problema de saúde pública no Brasil e destas destacam-se aquelas causadas por Flavivírus, dos quais onze já foram descritos no Brasil. Destes, dois importantes em saúde pública, e que pertencem ao sorocomplexo da Encefalite Japonesa, são o vírus da encefalite de Saint Louis (SLEV) e o Rocio (ROCV). O vírus Oeste do Nilo (WNV), introduzido no continente americano em 1999, ainda não foi detectado no Brasil, contudo sua introdução é muito provável. Neste estudo, avaliou-se a circulação de SLEV, ROCV e WNV em cavalos, por tentativas de isolamento viral e inquérito soro-epidemiológico. As tentativas de isolamento viral, em 11 tecidos cerebrais de cavalos do estado da Paraíba, resultaram negativas. O inquérito sorológico, por IgG-ELISA tendo como antígeno peptídeos recombinantes do domínio III da proteína de envelope de SLEV, WNV e ROCV, foi utilizado em 753 soros de animais dos estados de São Paulo, Mato Grosso do Sul, Minas Gerais, Rio de Janeiro e Paraíba. Soros de 271 cavalos foram positivos para SLEV (35,98%), 254 para WNV (33,73%) e 144 para ROCV (19,12%). Portanto, o ELISA mostrou-se adequado, diagnosticando infecções prévias por estes Flavivírus. Também, observou-se intensa circulação destes vírus infectando cavalos nos locais de estudo. Ainda, obteve-se, pela primeira vez, evidencia de que WNV foi introduzido no Brasil e encontra-se a infectar cavalos nos estados pesquisados exceto Minas Gerais. Finalmente, o inquérito sorológico em cavalos mostrou-se uma abordagem adequada à vigilância das flaviviroses por SLEV, ROCV e WNV no Brasil. / Arboviruses are a serious public health problem in Brazil and, from these, the most important are caused by Flavivirus. Eleven Flavivirus have been described in Brazil. Of these, Saint Louis Encephalitis Virus (SLEV) and Rocio Virus (ROCV) are major public health problems and belongs to the Japanese Encephalitis Serocomplex. West Nile Virus (WNV), introduced in the American continent in 1999, has not yet been detected in Brazil. In this study, it was evaluated the circulation of SLEV, WNV and ROCV in horses, by viral isolation attempts and a serosurvey. Viral isolation attempts were performed in 11 brain tissues of horses from Paraíba state with negative results. It was used for the serosurvey, an IgG-ELISA with recombinant peptides of domain III of SLEV, WNV and ROCV envelope protein as antigens. Sera from 753 animals from São Paulo, Mato Grosso do Sul, Minas Gerais, Rio de Janeiro and Paraíba states were tested, and 271 of them were positive for SLEV (35,98%), 254 for WNV (33,73%) and 144 for ROCV (19,12%). Therefore, this ELISA has been a suitable approach for diagnosis of ancient infections by these viruses. An intense circulation of flaviviruses infecting horses was observed in the study sites. Besides, it was found, for the first time, the presence of WNV in Brazil, infecting horses from all the studied states with the only exception of Minas Gerais. Finally, serosurvey in horses proved to be an appropriate approach for surveillance of Flavivirus infections by SLEV, WNV and ROCV.
7

Validação e uso de transcrição reversa seguida da reação em cadeia pela polimerase em tempo real (RT-qPCR) para a vigilância e diagnóstico de flavivírus transmitidos por mosquitos circulantes no Brasil / Validation and use of reverse transcription followed by real-time polymerase chain reaction (RT-qPCR) for the surveillance and diagnosis of flavivirus transmitted by mosquitoes in Brazil

Mariana Sequetin Cunha 21 May 2018 (has links)
Os flavivírus são considerados uma séria ameaça à saúde pública em diversas partes do mundo, pois muitos são agentes altamente patogênicos a seres humanos e animais, tais como os vírus da febre amarela, vírus do Oeste do Nilo, vírus da encefalite japonesa e vírus da dengue, capazes de causar encefalites ou febres hemorrágicas em seus hospedeiros. Muitos deles têm avançado a diferentes regiões geográficas onde sua circulação não havia sido detectada previamente, causando novos surtos. O diagnóstico clínico destas infecções é, muitas vezes, difícil, devido ao grande número de sintomas apresentados, que podem se confundir com outras enfermidades de diferentes causas etiológicas. Os principais métodos diretos utilizados atualmente no Brasil para detecção destes vírus são a inoculação intracerebral em camundongos neonatos, inoculação em culturas de células e RTPCR específica. O presente trabalho tem como objetivos avaliar a sensibilidade e validar a detecção dos vírus pertencentes ao gênero Flavivirus circulantes no Brasil por meio de uma reação single de RT-PCR em tempo real e implementá-la, tanto na rotina diagnóstica de casos com suspeita de arbovirose como na pesquisa de amostras de campo para monitoramento viral. Amostras dos flavivírus padrões da Febre Amarela, Bussuquara, Iguape, Ilheus, Encefalite de Saint Louis, Cacipacore e Zika foram quantificados por titulação em unidades formadoras de placa (UFP) ou TCID50 para se avaliar os limites de detecção para cada um deles por RT-qPCR que detecta o gênero Flavivirus. Os limites encontrados variaram de 0,01 UFP, para o vírus Ilheus, a 1 UFP, para os vírus da Febre Amarela e Iguape, e 1x101,6 TCID50/100µL para o vírus Bussuquara. Além disso, o presente trabalho foi capaz de identificar, após sequenciamento de cDNA gerado, os vírus Zika, isolado de um paciente febril, e os vírus Ilheus e Iguape, isolados a partir de diferentes espécies de Culicídeos, após uma única reação de RT-qPCR, e um possível novo flavivírus específico de insetos, isolado de mosquitos Aedes coletados em Guapiaçu, São Paulo. Não houve sinal de amplificação para os Alphavirus Mayaro e Chikungunya. O presente protocolo mostrou-se com alta sensibilidade e especificidade, podendo dessa forma ser utilizado para o diagnóstico diferencial dos diferentes flavivírus que ocorrem no Brasil, bem como para estudos de monitoramento viral em animais sentinelas e vetores, colaborando dessa forma com a saúde pública. Pode-se, ainda, detectar possíveis novos vírus específicos de artrópodes / Flaviviruses are considered a serious threat to public health in many parts of the world, as many are highly pathogenic to humans and animals, such as Yellow Fever virus, West Nile virus, Japanese encephalitis virus and dengue virus, which are capable of causing encephalitis or hemorrhagic fever in their hosts. Many of them have spread to different geographic regions where their circulation had not been detected previously, causing new outbreaks. Diagnosis of these infections is often difficult, due to the large number of symptoms presented, which can be confused with other diseases of different etiological causes. The main direct methods currently used in Brazil for detecting these viruses are intracerebral inoculation in neonatal mice, inoculation in cell cultures and specific RT-PCR. The present work aims to evaluate the sensitivity and validate the detection of viruses belonging to the genus Flavivirus circulating in Brazil through a single real-time RT-PCR reaction and to implement it, both in the diagnostic routine of cases with arbovirus suspicions and in field samples for viral monitoring. Samples of the standard flaviviruses Yellow Fever, Bussuquara, Iguape, Ilheus, Saint Louis Encephalitis, Cacipacore and Zika were quantified by titration by plaque forming units (UFP) or TCID50 to evaluate the detection limits for each of them by RT- qPCR that detects genus Flavivirus. The limits found ranged from 0.01 PFU for Ilheus virus to 1 PFU for Yellow Fever and Iguape viruses and 1x101.6 TCID50 / 100L for the Bussuquara virus. In addition, the present work was able to identify, after cDNA sequencing Zika virus, isolated from a febrile patient, and both Ilheus and Iguape viruses, isolated from different species of Culicidae, and a possible new insect-specific flavivirus, isolated from Aedes mosquitoes collected in Guapiaçu, São Paulo. The Alphaviruses Mayaro and Chikungunya were not amplified. The present protocol shoed high sensitivity and specificity, and therefore it may may be used for the differential diagnosis of the different flaviviruses that occur in Brazil, as well as for viral monitoring studies in sentinel animals and vectors, thus collaborating with public health. It is also possible to detect new flavivirus that are arthopode-specific.
8

Validação e uso de transcrição reversa seguida da reação em cadeia pela polimerase em tempo real (RT-qPCR) para a vigilância e diagnóstico de flavivírus transmitidos por mosquitos circulantes no Brasil / Validation and use of reverse transcription followed by real-time polymerase chain reaction (RT-qPCR) for the surveillance and diagnosis of flavivirus transmitted by mosquitoes in Brazil

Cunha, Mariana Sequetin 21 May 2018 (has links)
Os flavivírus são considerados uma séria ameaça à saúde pública em diversas partes do mundo, pois muitos são agentes altamente patogênicos a seres humanos e animais, tais como os vírus da febre amarela, vírus do Oeste do Nilo, vírus da encefalite japonesa e vírus da dengue, capazes de causar encefalites ou febres hemorrágicas em seus hospedeiros. Muitos deles têm avançado a diferentes regiões geográficas onde sua circulação não havia sido detectada previamente, causando novos surtos. O diagnóstico clínico destas infecções é, muitas vezes, difícil, devido ao grande número de sintomas apresentados, que podem se confundir com outras enfermidades de diferentes causas etiológicas. Os principais métodos diretos utilizados atualmente no Brasil para detecção destes vírus são a inoculação intracerebral em camundongos neonatos, inoculação em culturas de células e RTPCR específica. O presente trabalho tem como objetivos avaliar a sensibilidade e validar a detecção dos vírus pertencentes ao gênero Flavivirus circulantes no Brasil por meio de uma reação single de RT-PCR em tempo real e implementá-la, tanto na rotina diagnóstica de casos com suspeita de arbovirose como na pesquisa de amostras de campo para monitoramento viral. Amostras dos flavivírus padrões da Febre Amarela, Bussuquara, Iguape, Ilheus, Encefalite de Saint Louis, Cacipacore e Zika foram quantificados por titulação em unidades formadoras de placa (UFP) ou TCID50 para se avaliar os limites de detecção para cada um deles por RT-qPCR que detecta o gênero Flavivirus. Os limites encontrados variaram de 0,01 UFP, para o vírus Ilheus, a 1 UFP, para os vírus da Febre Amarela e Iguape, e 1x101,6 TCID50/100µL para o vírus Bussuquara. Além disso, o presente trabalho foi capaz de identificar, após sequenciamento de cDNA gerado, os vírus Zika, isolado de um paciente febril, e os vírus Ilheus e Iguape, isolados a partir de diferentes espécies de Culicídeos, após uma única reação de RT-qPCR, e um possível novo flavivírus específico de insetos, isolado de mosquitos Aedes coletados em Guapiaçu, São Paulo. Não houve sinal de amplificação para os Alphavirus Mayaro e Chikungunya. O presente protocolo mostrou-se com alta sensibilidade e especificidade, podendo dessa forma ser utilizado para o diagnóstico diferencial dos diferentes flavivírus que ocorrem no Brasil, bem como para estudos de monitoramento viral em animais sentinelas e vetores, colaborando dessa forma com a saúde pública. Pode-se, ainda, detectar possíveis novos vírus específicos de artrópodes / Flaviviruses are considered a serious threat to public health in many parts of the world, as many are highly pathogenic to humans and animals, such as Yellow Fever virus, West Nile virus, Japanese encephalitis virus and dengue virus, which are capable of causing encephalitis or hemorrhagic fever in their hosts. Many of them have spread to different geographic regions where their circulation had not been detected previously, causing new outbreaks. Diagnosis of these infections is often difficult, due to the large number of symptoms presented, which can be confused with other diseases of different etiological causes. The main direct methods currently used in Brazil for detecting these viruses are intracerebral inoculation in neonatal mice, inoculation in cell cultures and specific RT-PCR. The present work aims to evaluate the sensitivity and validate the detection of viruses belonging to the genus Flavivirus circulating in Brazil through a single real-time RT-PCR reaction and to implement it, both in the diagnostic routine of cases with arbovirus suspicions and in field samples for viral monitoring. Samples of the standard flaviviruses Yellow Fever, Bussuquara, Iguape, Ilheus, Saint Louis Encephalitis, Cacipacore and Zika were quantified by titration by plaque forming units (UFP) or TCID50 to evaluate the detection limits for each of them by RT- qPCR that detects genus Flavivirus. The limits found ranged from 0.01 PFU for Ilheus virus to 1 PFU for Yellow Fever and Iguape viruses and 1x101.6 TCID50 / 100L for the Bussuquara virus. In addition, the present work was able to identify, after cDNA sequencing Zika virus, isolated from a febrile patient, and both Ilheus and Iguape viruses, isolated from different species of Culicidae, and a possible new insect-specific flavivirus, isolated from Aedes mosquitoes collected in Guapiaçu, São Paulo. The Alphaviruses Mayaro and Chikungunya were not amplified. The present protocol shoed high sensitivity and specificity, and therefore it may may be used for the differential diagnosis of the different flaviviruses that occur in Brazil, as well as for viral monitoring studies in sentinel animals and vectors, thus collaborating with public health. It is also possible to detect new flavivirus that are arthopode-specific.
9

Contribution of different components of innate and adaptive immunity to severity of flavivirus-induced encephalitis in susceptible and resistant hosts

Shomiad Shueb, Rafidah Hanim January 2008 (has links)
[Truncate abstract] Flaviviruses are small, positive-stranded RNA viruses belonging to the family Flaviviridae. Flavivirus infection in humans could cause diseases ranging from febrile illnesses to fatal encephalitis. Mice provide a useful small animal model to study flavivirus-induced encephalitis in humans since mice also develop encephalitis during flavivirus infection. Some strains of mice have been shown to be resistant to flavivirus challenge and this resistance is conferred by a single autosomal dominant gene, designated as Flvr. Recently, OAS1b gene has been identified to be a gene candidate for Flvr. Several congenic resistant mouse strains have been developed by introducing resistance genes from outbred or wild mice onto the genetic background of susceptible C3H mice. These new resistant strains that carry different allelic variants at the Flv locus include C3H/PRI-Flvr (RV), C3H.MOLD-Flvmr (MOLD) and C3H.M.domesticus-Flvr-like (DUB), the latter two being developed in the same laboratory in which the work described in this thesis was accomplished. Preliminary studies in this laboratory found that flavivirus resistant mice are vulnerable to certain flavivirus infections, particularly when challenged by intracerebral (i.c.) route. Intracerebral (i.c.) challenge with flaviviruses such as West Nile virus (WNV) Sarafend strain and Kunjin virus (KUNV) MRM16 strain were found to induce high mortality in flavivirus resistant mice while infection with Murray Valley encephalitis virus (MVEV) OR2 strain did not cause any apparent disease in the same mice. ... Thus, it can be concluded that CD8+ T cells exerted harmful effect to resistant DUB mice during KUNV i.c. infection by producing excessive IFN[gamma] that could be toxic, causing functional loss of the CNS cells. It was shown from in vitro studies that WNV had the highest tropism for macrophages and dendritic cells, followed by KUNV. MVEV however did not replicate well in these cells. This combined with the data from the in vivo studies indicates that macrophages might be involved in the pathogenesis of intraperitoneal (i.p.) infection of WNV but not KUNV and MVEV. The reason for this could be that the production of KUNV in macrophages may not be high enough to induce viraemia and subsequent fatal encephalitis in mice. In contrast, MVEV appears to use different mechanism or cells for virus dissemination. Although macrophages may not be involved in KUNV pathogenesis after i.p. infection, the fact that macrophages support KUNV replication in vitro may indicate the possibility that blood-borne macrophages were recruited to the brain where they can get infected with KUNV during i.c. infection and therefore could participate in KUNV pathogenesis in DUB mice. This study provides evidence for the first time on the detrimental effect of host antiviral immunity and inflammatory mediators during flavivirus i.c. infection in resistant mice. However, it also launches a new question on the selective cell tropism of KUNV versus MVEV responsible for inducing different pattern of immune responses and consequently leading to different outcomes of infection in resistant mice.
10

Detecció d'arbovirus en vectors a Espanya

Aranda Pallero, Carlos 30 June 2010 (has links)
Entre els anys 2001 i 2005 es van capturar i analitzar 72.895 femelles de mosquits (Diptera: Culicidae) i 6.871 de flebòtoms (Diptera: Psychodidae) en les estacions d'abundància amb l'objectiu de detectar la presència de genoma d'arbovirus en diferents àrees d'Espanya, en especial en zones humides. L'estudi forma part d'un de més general que tracta de la transmissió d'arbovirus en quatre dels aiguamolls més importants d'Espanya que es troben a Girona, Barcelona, Tarragona i Huelva.Els insectes es van recollir amb esquer humà, amb trampes de CO2 i amb trampes CDC i es van agrupar en pools segons la data de captura, la localitat i l'espècie. Pel que fa als flebòtoms, les mostres es van obtenir a partir del 2002 a Barcelona i Huelva i es van identificar com a subfamília.Els culícids es van agrupar en 4.723 pools i pertanyien a 20 espècies dels gèneres Anopheles, Aedes, Ochlerotatus, Culex, Culiseta, Coquillettidia i Uranotaenia i els flebòtoms es van agrupar en 236 pools com a tals.Mentre es duia a terme l'estudi, es va detectar el mosquit invasor -Aedes (Stegomyia) albopictus (Skuse)- per primera vegada a Espanya, concretament a Sant Cugat del Vallès, durant l'estiu del 2004. Mitjançant inspeccions immediatament posteriors es va comprovar l'existència d'importants poblacions a la zona, i se'n va confirmar l'establiment. Aquesta és la primera notificació de l'espècie esmentada a la península Ibèrica. Es van analitzar totes les femelles capturades posteriorment a l'àrea d'estudi.L'espècie de culícid més abundant va ser Ochlerotatus caspius (40,9 %), seguida de Culex pipiens (32,3 %), Culex theileri (10,9 %), Anopheles atroparvus (6,6 %), i Culex modestus (4,6 %).Es van analitzar homogenats dels vectors per detectar directament ARN d'arbovirus dels gèneres Alphavirus, Flavivirus i Phlebovirus. No s'ha trobat ARN d'arbovirus patògens coneguts. En el cas dels mosquits, 111 pools van ser positius a Flavivirus, l'únic gènere detectat en aquest grup taxonòmic. Les seqüències de Flavivirus identificades són diferents de qualsevol Flavivirus de mosquit conegut i majoritàriament properes al virus Kamiti River (KRV) o al virus cell fusing agent (CFA), excepte en dos pools d'Andalusia que es troben properes al grup de virus transmesos per artròpodes. Per a totes les zones i espècies, es va calcular l'estimació del màxim de versemblança de la taxa d'infecció o the maximum likelihood estimation infection rate (MLE). Ae. albopictus tingué la MLE més alta, de 47,14, seguida per Aedes vexans amb 43,67 en el conjunt de l'àrea d'estudi. Per sota d'aquestes espècies hi havia Culiseta annulata, amb 36,00. Les espècies més abundants, Oc. caspius i Cx. pipiens, va obtenir valors MLE baixos (0,94 i 0,38 respectivament) en el conjunt de tota l'àrea.En el cas dels flebòtoms, 10 pools (9 dels quals de Barcelona) van donar positiu a Flavivirus semblants a Culex Flavivirus (CxFV). És la primera vegada que es troba genoma d'aquest gènere en flebòtoms de fora de l'Àfrica. En 8 pools de Barcelona es va trobar un Phlebovirus similar al complex Nàpols i al virus Massilia.Cal assenyalar que en el cas d'alguns mosquits, en especial en mostres dels gèneres Aedes i Ochlerotatus, el genoma detectat probablement eren seqüències d'ADN integrades en el genoma dels mosquits. Aquest fet l'han observat recentment altres autors.El 2006, seguint amb la campanya de detecció d'arbovirus, es va trobar, entre 436 pools dels aiguamolls de Catalunya i 9 espècies de mosquit, un de positiu a un Flavivirus identificat com a virus Usutu (USUV) en un pool de 3 Cx. pipiens obtingut a Viladecans (Barcelona). Les dades d'homologia van mostrar que la soca espanyola pertanyia a l'USUV però que era més propera a mostres africanes d'USUV que a les obtingudes a Europa central. / With the aim of assessing the presence of arbovirus genome in vectors in different areas, especially wetlands, in Spain, a total of 72,895 female mosquitoes (Diptera: Culicidae) and 6,871 sandflies (Diptera: Psychodidade) were trapped during their season of abundance, and analyzed between the years 2001 and 2005. The study formed part of general arbovirus transmission research in four of the most important wetlands in Spain in the provinces of Girona, Barcelona, Tarragona, and Huelva.Insects were collected using human bait, CO2 traps, or light traps, and they were pooled according to date of collection, location, and species. In the case of sandflies, the period of study started in 2002 in Barcelona and Huelva and species were not identified. Mosquitoes were sorted into 4,723 pools belonging to 20 Culicidae species from the Anopheles, Aedes, Ochlerotatus, Culex, Culiseta, Coquillettidia, and Uranotaenia genera. Sandflies were sorted into 236 pools as a whole.During the study, the invasive mosquito Aedes (Stegomyia) albopictus (Skuse) was detected for the first time in Spain, in Sant Cugat del Vallès during August 2004. Dense populations of adults and larvae were found in subsequent surveys, confirming the establishment of this species in this area. This is the first report of the establishment of Ae. albopictus in the Iberian Peninsula. All captured females in the studied area belonging to this species were analyzed.The most abundant species was Ochlerotatus caspius (40.9 %), followed by Culex pipiens (32.3 %), Culex theileri (10.9 %), Anopheles atroparvus (6.6 %), and Culex modestus (4.6 %).Arboviral RNA was directly detected from vector homogenates for the genera Alphavirus, Flavivirus, and Phlebovirus. No arboviral RNA from known pathogenic arboviruses was found. In the case of mosquitoes, 111 pools tested positive for unknown mosquito Flavivirus, the only genus detected in this taxonomic group. The Flavivirus sequences identified were different from all known Flavivirus mosquito viruses, but very close to Kamiti River virus (KRV) or cell fusing agent virus (CFA) with the exception of two pools from Andalusia, close to the group of arthropod borne viruses. The maximum likelihood estimation infection rate (MLE) was calculated for all regions and species. Ae. albopictus had the highest MLE at 47.14, followed by Aedes vexans with 43.67 over the entire area. These species were followed by Culiseta annulata, with 36.00. The most common species, Oc. caspius and Cx. pipiens, had low MLE values -0.94 and 0.38, respectively- over the area as a whole.In the case of sandflies, 10 pools (9 in Barcelona) tested positive for a Flavivirus similar to Culex Flavivirus (CxFV) being this, the first time that Flavivirus genome is detected in sand flies outside Africa. Phlebovirus viruses similar to Naples complex and Massilia were found in 8 sandflies pools, all from Barcelona area.In some samples of mosquitoes, especially in genera Aedes and Ochlerotatus, detected genome was probably DNA sequences integrated in the mosquito genome as has been observed recently by other authors.In 2006, surveillance monitoring samples carried out in Catalonia detected, in 436 pools belonging to 9 mosquito species, a positive for Flavivirus identified as Usutu virus (USUV) in a pool of 3 Cx. pipiens obtained from the town of Viladecans, Barcelona. The homology data showed that the Spanish strain belongs to USUV species and is more related to the African USUV isolates than to central European isolates.

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