• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 25
  • 19
  • 6
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 61
  • 16
  • 13
  • 11
  • 9
  • 9
  • 8
  • 8
  • 8
  • 7
  • 7
  • 7
  • 7
  • 6
  • 5
  • 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.
51

Infekční nemoci přenášené členovci / Infectious diseases transmitted by arthropods

NOVÁKOVÁ, Petra January 2013 (has links)
This thesis deals with infectious diseases transmitted by arthropods in the Czech Republic in period of 2002 - 2011. Meeting the objectives and answer the research questions, I managed using secondary analysis of reported cases infectious diseases transmitted by arthropods in the information system for reporting and recording of infectious diseases - EPIDAT and literature review and subsequent analysis of scientific articles. Important additional informations were provided by State Veterinary Institute in Prague and the National Reference Laboratory for arboviruses in Ostrava. Thesis does not deal with number of single values, but it is focused on epidemiological severity of analyzed cases, severity of clinical course and risk of introducing infection in the Czech Republic. Theoretical part of the thesis describes selected arboviruses infections. Tick-borne encephalitis is one of the most important diseases transmitted by arthropods in our surroundings. Number of reported cases of tick-borne encephalitis was quite constant in monitored period 2002 - 2011, according to my research and statistical verification. Highest morbidity was in 2006. The same year the highest incidence of disease Tick-borne encephalitic was reported in region of Vysočina. This number is far closer to number of reported cases in region of South Bohemia which was the most affected region thought the entire period. Prevention exists against tick-borne encephalitis. It is vaccination which is recommended for people staying in natural foci of infection in the Czech Republic and abroad. In the Czech republic becomes more important West Nile fever. Increased incidence of this disease is recorded in the USA, but also in many European countries (eg Greece, Hungary, Italy) in recent years. One of the goals of this thesis is to characterize the surveillance of West Nile fever in the Czech republic. Monitoring antibody titer against West Nile virus in the serum of horses is one of the basic elements of surveillance of this disease in our country. 5 samples of the blood serum was increased titers of antibodies to West Nile virus. Various geographic distribution of horses and high specific antibody titers indicate increasing activity of West Nile virus. Clinical disease of horses not being recorded in the Czech republic. In the field of human medicine have been reported three imported cases of West Nile fever. Other arboviruses infections, that appeared in our country, is dengue disease and viral disease Chikungunya. In the monitored period there were a total of 98 reported cases of imported disease. Most cases were imported from India. Three cases of Chikungunya disease were reported in 2006 in connection with a stay on the island of Mauritius, where was the epidemic at this time. People can travel freely and there is the risk of importing diseases from the tropics and subtropics. Some infections transmitted by arthropods are in areas where it was previously absent recently. Prevention is essential. Specific and non-specific prevention. Another important element of prevention is strict adherence to methods for surveillance of disease.Viral infections transmitted by arthropods are among the most important emergent infectious diseases. In addition to malaria, malnutrition and helminth infection are the largest public health problem, not only in third world countries.
52

Investigação molecular de flavivírus em pacientes febris com suspeita de dengue em Mato Grosso

Heinen, Letícia Borges da Silva 28 March 2014 (has links)
Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2017-09-15T13:37:53Z No. of bitstreams: 1 DISS_2014_Letícia Borges da Silva Heinen.pdf: 4369897 bytes, checksum: 2e00a8b07d093787dbdb2e23dd6ac34e (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-09-19T12:59:17Z (GMT) No. of bitstreams: 1 DISS_2014_Letícia Borges da Silva Heinen.pdf: 4369897 bytes, checksum: 2e00a8b07d093787dbdb2e23dd6ac34e (MD5) / Made available in DSpace on 2017-09-19T12:59:17Z (GMT). No. of bitstreams: 1 DISS_2014_Letícia Borges da Silva Heinen.pdf: 4369897 bytes, checksum: 2e00a8b07d093787dbdb2e23dd6ac34e (MD5) Previous issue date: 2014-03-28 / CNPq / O gênero Flavivirus, família Flaviviridae, alberga arbovírus como os vírus dengue (DENV) e da febre amarela, que possuem importância médica e são envolvidos em epidemias de doença febril em áreas urbanas e rurais em regiões tropicais e subtropicais. No Brasil, atualmente, o DENV e o vírus da encefalite de Saint Louis (SLEV) são os dois flavivírus circulantes em áreas urbanas mais frequentes. Desde a introdução e emergência dos diferentes sorotipos de DENV a partir da década de 1980, extensas epidemias de febre do dengue vêm sendo reladas por todo o país. O SLEV, anteriormente reconhecido apenas em ciclos enzoóticos e com pouca relevância médica no Brasil, tem sido implicado em casos de doença febril durante epidemia de dengue no sudeste do país. O objetivo deste estudo foi investigar a circulação de flavivírus em pacientes com doença febril aguda com suspeita de dengue em Mato Grosso (MT) em 2011 e 2012. Material e Métodos: 604 amostras de soro obtidas entre outubro de 2011 e julho de 2012 de pacientes com doença febril aguda suspeita de dengue com até cinco dias do início dos sintomas em MT foram submetidas à multiplex semi-nested RT-PCR para a pesquisa de flavivírus, como os quatro sorotipos de DENV, SLEV, vírus da febre amarela, do Oeste do Nilo, Rocio, Bussuquara, Iguape e Ilhéus. Amostras positivas foram testadas em pelo menos duas reações independentes de single-nested RT-PCR e submetidas a sequenciamento nucleotídico de região do gene da glicoproteína de envelope para análise filogenética. Resultados: Dentre os 604 pacientes, 315 (52,2 %) foram positivos para DENV-4, 24 (4,0 %) para DENV-1, 3 (0,5 %) para SLEV, 1 (0,2 %) para DENV-2 e 1 (0,2 %) para DENV-3. Todas as amostras eram de pacientes oriundos de áreas urbanas de 17 municípios de MT. Entre as amostras positivas, 9 eram co-infecções entre DENV-1/DENV-4, 1 entre DENV-2/DENV-4, 2 por SLEV/DENV-4 e 1 entre SLEV/DENV-1/DENV-4. Os demais flavivírus pesquisados não foram detectados. Amostras negativas para flavivírus totalizaram 273/604 (45,20 %). Discussão: A ocorrência das arboviroses na população geralmente é subestimada, devido a fatores como quadro clínico inespecífico, infecções inaparentes e ausência de diagnóstico diferencial. O DENV-4 foi introduzido no MT em 2012, responsável pela maior casuística nas cidades da Baixada Cuiabana. Co-infecções são frequentes quando há circulação hiperendêmica dos quatro sorotipos do DENV, situação já relatada no Brasil em Manaus e Rio de Janeiro em 2011. O SLEV foi detectado em pacientes de Cuiabá e Várzea Grande. Infecções por SLEV são primariamente inaparentes ou brandas. Em MT, espécies de Culex e outros vetores deste virus são amplamente dispersas. Como humanos são hospedeiros finais e apresentam baixa viremia, sua ocorrência é provavelmente subestimada. Conclusão: DENV-1 e DENV-4 foram os flavivírus identificados com maior frequência. Os quatro sorotipos do DENV foram detectados em Cuiabá e infecções esporádicas pelo SLEV foram identificadas em pacientes co-infectados com o DENV-4 ou o DENV-4/DENV-1 em Cuiabá e Várzea Grande, indicando que outros arbovírus podem circular silenciosamente durante epidemia de dengue em áreas urbanas em MT. / The genus Flavivirus, Flaviviridae family, comprises arboviruses such as the medical important dengue virus (DENV) and yellow fever virus, involved in febrile illness epidemics in urban and rural areas of tropical and subtropical regions. In Brazil, DENV and Saint Louis encephalitis (SLEV) virus are currently the two most important flaviviruses circulating in urban areas. Since the introduction and emergence of different DENV serotypes in the 1980´s, extensive dengue outbreaks have been reported throughout the country.SLEV, previously recognized only in enzootic cycles without medical relevance in Brazil, has been implicated to febrile illness etiology during dengue fever outbreaks in the Southeast region. The aim of this study was to investigate the circulation of flaviviruses in patients with acute febrile illness suspected of harboring dengue in Mato Grosso (MT) between 2011 and 2012. Material and Methods: 604 serum samples obtained between October 2011 and July 2012 from patients with acute febrile illness suspected of dengue lasting less than 5 days in MT were subjected to multiplex semi-nested RT-PCR for flaviviruses, including all four serotypes of DENV, SLEV Yellow Fever, West Nile, Rocio, Bussuquara, Iguape and Ilheus viruses. Positive samples were tested at least twice in independent single-nested RT-PCR reactions and subjected to nucleotide sequencing of the envelope glycoprotein (E) gene region for phylogenetic analysis. Results: Among 604 patients, 315 (52.2 %) were positive for DENV-4, 24 (4.0 %) for DENV-1, three (0.5 %) for SLEV, one (0.2 %) for DENV-2 and one (0.2 %) for DENV-3. All patients are residents in urban areas of 17 cities of MT. Among then, 9 were co-infections among DENV-1/DENV-4, 1 between DENV-2/DENV-4, two between SLEV/DENV-4 and one with SLEV/DENV-1/DENV-4. The other flaviviruses were not detected. Negative samples for flavivirus totaled 273/604 (45.20 %). Discussion: The occurrence of arboviruses in the population generally is underestimated, probably due to unapparent infection or unspecific clinical presentation, associated to the absence of differential diagnosis. The DENV-4 serotype was introduced in MT in 2012, responsible for the largest number of cases in Cuiabá and Varzea Grande. Co-infections are common when hiperendemic circulation of all four serotypes of DENV is observed. This situation has already been reported in Brazil in Manaus and Rio de Janeiro cities in 2011. Three patients were positive for SLEV in Cuiaba and Várzea Grande. SLEV infections are primarily mild or unapparent. In MT, species of Culex and other vectors are widely dispersed. As humans are final hosts and, therefore, present low titer viremia, the occurrence of SLEV in the population is probably underestimated. Conclusion: DENV-1 and DENV-4 were the most frequently flaviviruses identified. The four DENV serotypes were detected in Cuiaba and sporadic SLEV infections were identified in patients co-infected with DENV-4 or DENV-1/DENV-4 in Cuiaba and Várzea Grande, indicating that other arboviruses may circulate silently during dengue epidemics in urban areas of MT.
53

Detecção do segmento S do vírus Oropouche em pacientes e em Culex quinquefasciatus em Mato Grosso, Brasil

Cardoso, Belgath Fernandes 26 March 2015 (has links)
Submitted by Valquíria Barbieri (kikibarbi@hotmail.com) on 2018-04-18T20:33:59Z No. of bitstreams: 1 DISS_2015_Belgath Fernandes Cardoso.pdf: 3865065 bytes, checksum: 3b7d79b4224429f58cb6ca5c3d96d7e9 (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2018-04-27T17:29:40Z (GMT) No. of bitstreams: 1 DISS_2015_Belgath Fernandes Cardoso.pdf: 3865065 bytes, checksum: 3b7d79b4224429f58cb6ca5c3d96d7e9 (MD5) / Made available in DSpace on 2018-04-27T17:29:40Z (GMT). No. of bitstreams: 1 DISS_2015_Belgath Fernandes Cardoso.pdf: 3865065 bytes, checksum: 3b7d79b4224429f58cb6ca5c3d96d7e9 (MD5) Previous issue date: 2015-03-26 / CAPES / O gênero Orthobunyavirus, família Bunyaviridae, alberga arbovírus de importância médica. Estes estão envolvidos em epidemias de doença febril em áreas tropicais. No Brasil, o vírus Oropouche (OROV) é considerado o arbovírus mais frequente após o vírus da dengue (DENV). O objetivo deste estudo foi investigar a circulação de orthobunyavírus em Mato Grosso (MT). 529 amostras de soro obtidas entre outubro de 2011 e julho de 2012 de pacientes com doença febril aguda suspeita de dengue com até cinco dias do início dos sintomas em MT e 387 pools de mosquitos Cx quinquefasciatus capturados entre janeiro e abril de 2013 foram submetidos à nested RT-PCR para o segmento S de orthobunyavírus pertencentes ao sorogrupo Simbu. Amostras positivas foram testadas em pelo menos duas reações independentes e submetidas a sequenciamento nucleotídico para análise filogenética. Inoculou-se as amostras positivas em células vero. Dentre os 529 pacientes, 5 (0,94%) foram positivos para orthobunyavirus do sorogrupo Simbu por nested RT-PCR e isolamento viral. O vírus foi isolado de 3/8 pools. O segmento S do OROV foi identificado em cinco pacientes, quatro do sexo feminino, com 14-62 anos. Dois pacientes encontravam-se co-infectados com DENV-4. Estes pacientes são oriundos das cidades de Cuiabá (n=3), Várzea Grande (n=1) e Nova Mutum (n=1), todos residentes em área urbana, que apresentavam febre, cefaleia, dor retroorbital, mialgia, artralgia, prostação e náuseas. 8/387 pools de Cx. quinquefasciatus foram positivos para o segmento S do OROV por nested-RT-PCR, com taxa mínima de infecção (MIR) de 2,3 por 1000 mosquitos. As sequências obtidas do segmento S apresentaram 98% a 100% de homologia com o mesmo segmento das cepas do OROV verificadas no GenBank. A análise filogenética indica que as amostras de humanos e mosquitos pertencem ao subgenótipo Ia, similares a cepas do Pará obtidas de humanos, preguiças, Aedes (Ochlerotatus) serratus e Cx. quinquefasciatus. O genótipo I é o mais conservado e frequente no Brasil dentre os genótipos do OROV. Cx. quinquefasciatus, culicídeo de maior abundância em Cuiabá, é considerado vetor secundário do OROV em área urbana. Culicoides paraensis, principal vetor do OROV em áreas urbanas na região amazônica, não foi capturado neste estudo. Sorologia para o OROV foi identificada em residentes de cidades do Pará afetadas pela rodovia Cuiabá-Santarém e em primatas do Pantanal Sul-matogrossense, corroborando com a identificação do OROV em cidades do MT geograficamente interligadas por esta mesma rodovia. Infecções esporádicas por um orthobunyavirus do sorogrupo Simbu, possivelmente o OROV, foram identificadas em pacientes de MT, além de oito pools de Cx. quinquefasciatus em Cuiabá, indicando que este mosquito possui capacidade vetorial e pode estar envolvido no ciclo urbano de transmissão do vírus no estado. / The genus Orthobunyavirus, family Bunyaviridae, contains medically importante arboviruses. These are involved in epidemics of febrile illness in tropical areas. In Brasil, Oropouche virus (OROV) is considered the most frequent arbovirus after dengue virus (DENV). The aim of this study was to investigate the circulation of orthobunyaviruses in Mato Grosso (MT). 529 serum samples collected between October, 2011 and July, 2012 of patients with acute febrile illness suspected of dengue for up to five days of symptom onset from MT and 387 pools of Cx. quinquefasciatus mosquitoes captured between January and April, 2013, were subjected to nested RT-PCR for the segment S of orthobunyaviruses belonging to Simbu serogroup. Positive samples were tested in at least two independent reactions and subjected to nucleotide sequencing for phylogenetic analysis. Positive samples were inoculated in vero cells. Among the 529 patients, five (0.94%) were positive for serogroup Simbu by nested RT-PCR and viral isolation. The virus was isolated from 3/8 pools. The OROV segment S was identified in five patients, four females, with 14-62 years-old. Two patients were co-infected with DENV-4. These patients are from Cuiabá (n=3), Várzea Grande (n=1) and Nova Mutum (n=1), all residents in urban areas, presenting fever, headache, retroorbital pain, myalgia, arthralgia, prostration and nausea. 8/387 pools of Cx. quinquefasciatus were positive for OROV segment S by nested-RT-PCR with a minimum infection rate (MIR) of 2.3 per 1,000 mosquitoes. The segment S nucleotide sequences presented 98% to 100% of homology with the same segment of OROV strains available in GenBank. Phylogenetic analysis indicate the human and mosquito samples belong to genotype Ia, similar to strains obtained in Pará from humans, sloths, Aedes (Ochlerotatus) serratus and Cx. quinquefasciatus. The genotype I is the most conserved among OROV genotypes. Cx. quinquefasciatus, the most abundant culicidae in Cuiabá, is considered a secondary vector for OROV in urban areas. Culicoides paraensis, the main vector for OROV in urban areas in the Amazon region, was not captured in the study. Serology for OROV was identified in humans in cities of Pará affected by the Cuiabá-Santarém highway and in primates in South Pantanal, corroborating for the findings in cities of MT geographically linked by the same highway. Sporadic infections by an orthobunyavirus from Simbu serogroup, possibly OROV, were identified in patients from MT, also eight Cx. quinquefasciatus pools from Cuiabá, indicating that has vectorial capacity and may be involved in the urban cycle of virus transmission in the state.
54

Développement d’un biomarqueur salivaire mesurant l’exposition de l’Homme aux piqûres des moustiques Aedes : applications aux risques de transmission et à l’évaluation de l’efficacité des stratégies de lutte contre les arboviroses / Development of a salivary biomarker for measuring the human exposure to Aedes mosquitoes bites : applications to evaluate the risk of arboviruses transmission and the efficacy of vector control

Elanga N'Dille, Clément Emmanuel 20 May 2014 (has links)
Les infections virales transmises à l'homme par les moustiques Aedes, sont en pleine émergence ou ré-émergence dans le monde entier. Le contrôle des populations de vecteurs reste la seule méthode de lutte. Pour un contrôle plus efficace, de nombreux efforts sont déployés pour développer de nouveaux indicateurs évaluant l'exposition de l'Homme aux piqûres des Aedes. Dans ce contexte, l'objectif de la thèse était de développer un biomarqueur, basé sur l'évaluation quantitative de la réponse anticorps (Ac) spécifique au peptide salivaire Nterm-34kDa d'Ae. aegypti chez les populations exposées. Pour cela, nous avons évalué le potentiel de cette réponse Ac spécifique à i) mesurer l'intensité d'exposition aux piqûres, ii) évaluer le risque de transmission des arboviroses et iii) évaluer l'efficacité des stratégies de lutte anti-vectorielle (LAV). Nos résultats ont montré qu'une réponse IgG anti-peptide Nterm-34kDa pouvait être détectée chez les individus exposés à Ae. aegypti et Ae. albopictus. Le niveau de cette réponse IgG spécifique augmentait entre les saisons de faibles densités de moustiques et celles de fortes densités, indiquant que ce candidat biomarqueur permettrait d'évaluer l'exposition aux piqûres des Aedes. La distribution spatiale similaire de la prévalence de nouvelles infections au virus de la dengue et la prévalence de la réponse IgG spécifique montrait également que ce candidat biomarqueur permettrait d'identifier des zones à risque de transmission. La comparaison des réponses IgG anti-peptide Nterm-34kDa avant et après les interventions de LAV, a montré qu'une baisse post-LAV de cette réponse Ac spécifique permettrait d'évaluer l'efficacité de la LAV contre les Aede. Ce biomarqueur salivaire pourrait donc représenter un indicateur de la réduction du contact homme-vecteur. L'ensemble de ces travaux montre que la réponse Ac spécifique au peptide salivaire Nterm-34kDa constitue un pertinent biomarqueur pour évaluer l'exposition de l'Homme aux vecteurs des arboviroses. La validation supplémentaire de ce biomarqueur et son développement sous forme de test rapide permettraient aux structures en charge de la surveillance des arboviroses et de la lutte anti-vectorielle, de disposer d'un outil complémentaire des indicateurs entomologiques et épidémiologiques de référence. / Human viral infections transmitted by Aedes mosquitoes are rapidly emerging or re-emerging worldwide. Vector control strategies remain currently the unique method to control these infections. To improve the effectiveness of this control, much effort is being devoted to develop new indicators for measuring the human exposure to Aedes bites. In this way, this project aimed to develop a biomarker based on the quantitative assessment of antibody response (Ab) to Ae. aegypti Nterm - 34kDa salivary peptide, in human exposed populations. We evaluated thus the potential of this specific Ab response to: i) measure the intensity of human exposure to Aedes bites, ii) assess the risk of transmission of arboviruses and iii) evaluate the efficacy of vector control strategies. Our results showed that a specific IgG response to Nterm-34kDa peptide could be detected in individuals exposed to Ae. aegypti or Ae. albopictus. The level of specific IgG response increased from the season of low mosquito densities to high densities one, indicating that this biomarker candidate could evaluate the intensity of exposure to the Aedes bites. The observed similar spatial distribution of the prevalence of new infections with dengue virus and specific IgG response showed that this biomarker candidate could identify areas at risk of transmission. The comparison of the specific IgG responses to Nterm-34kDa peptide before and after the vector control intervention showed a decline of the specific Ab response after implementation of control. It indicated that such salivary biomarker could assess the effectiveness of vector control against Aedes, and that this salivary biomarker could be an indicator of the reduction of man-vector contact. Altogether, the results of this work show that the specific IgG response to the Nterm-34kDa salivary peptide could be a relevant biomarker for assessing human exposure to arboviruses vectors. This promising indicator, developed as a rapid test, could represent a complementary tool for entomological and epidemiological surveillance of arboviruses diseases.
55

Perfil sorológico por inibição da hemaglutinação para arboviroses em residentes \"Ribeirinhos\" da região Amazônica e \"rurais\" do sudeste brasileiro. / Serological survey for Arboviruses by hemagglutination inhibition in Residents of Amazon region and country people in Southeastern of Brazil.

Maués, Fábio Carmona de Jesus 07 December 2010 (has links)
Neste trabalho foi feito uma investigação sorológica em moradores na região amazônica e moradores rurais do sudeste brasileiro, através do teste de inibição da hemaglutinação (HI) para a cepa vacinal da Febre Amarela mais 17 sorotipos diferentes de arbovírus, sendo quatro do gênero Alphavirus (ALP), nove do gênero Flavivirus (FLA) e cinco do gênero Orthobunyavirus (ORT), para verificar qual desses vírus estão circulando nessas regiões. Os resultados do HI foram divididos em quatro áreas: na cidade Machadinho dOeste (Rondônia) (N=285) tivemos para ALP=50 (17,54%), FLA=270 (94,74%), ORT=58 (20,35%) e negativos (NEG)=12 (4,20%). Nas pessoas que moram ao longo do Rio Machado (Rondônia) (N=343) tivemos ALP=99 (28,86%), FLA=229 (66,76%), ORT=41 (11,95%) e NEG=93 (27,10%). Na cidade Teodoro Sampaio (São Paulo) (N=78) tivemos FLA=55 (70,51%) e NEG=23 (29,5%). Na cidade Jacupiranga (São Paulo) (N=149) tivemos ALP=7 (4,7%), FLA=50 (33,56%), ORT=20 (13,42%) e NEG=84 (56,4%). Concluímos que os resultados obtidos sugerem a circulação desses vírus nas regiões estudadas. / In this work we performed a serological investigation in residents of Amazon region and country people who lives in Southeastern of Brazil, by hemagglutination inhibition (HI) for Yellow fever vaccine and 17 different serotype of arboviruses: four from the genus Alphavirus (ALP), nine from the genus Flavivirus (FLA), and five from the genus Orthobunyavirus (ORT), to try to ascertain which of these arboviruses are circulating in these areas. The results of HI were divided into four areas: In Machadinho dOeste city (Rondônia) (N=285) we had to ALP=50 (17,54%), FLA=270 (94,74%), ORT=58 (20,35%) and negatives (NEG)=12 (4,20%). In people who live along the Machado River (Rondônia) (N=343) we had to ALP=99 (28,86%), FLA=229 (66,76%), ORT=41 (11,95%) and NEG=93 (27,10%). In Teodoro Sampaio City (São Paulo) (N=78) we had to FLA=55 (70,51%) and NEG=23 (29,5%). In Jacupiranga City (São Paulo) (N=149) we had to ALP=7 (4,70%), FLA=50 (33,56%), ORT=20 (13,42%) and NEG=84 (56,4%). In conclusion, the obtained data suggest the circulation of these viruses in these regions.
56

Biodiversidade de Culicidae e sua interação com arboviroses e malária na Mata Atlântica / Biodiversity of Culicidae and its interaction with arboviruses and malaria in the Atlantic Forest

Laporta, Gabriel Zorello 24 April 2012 (has links)
Introdução - Interações complexas estão presentes entre a biodiversidade de mosquitos (Diptera, Culicidae) e as dinâmicas de transmissão de arbovírus e plasmódios que são agentes infecciosos que podem causar moléstias em humanos e outros animais. Objetivos - Aplicar método de distribuição potencial de habitats para mosquitos vetores de arbovírus e de plasmódios no Vale do Ribeira, sudeste do Estado de São Paulo, sub-região Serra do Mar da Mata Atlântica. Em escala local nessa região, relacionar a heterogeneidade espacial com a biodiversidade e esta com a dinâmica de transmissão de malária no Parque Estadual da Ilha do Cardoso. Métodos - Foram elaborados mapas de distribuição espacial dos vetores de arbovírus: Aedes serratus, Aedes scapularis e Psorophora ferox. Os mapas gerados para Anopheles cruzii, Anopheles bellator e Anopheles marajoara foram correlacionados com a distribuição espacial de malária. As correlações entre heterogeneidade espacial e biodiversidade de mosquitos foram estabelecidas com o emprego de modelos estatísticos de regressão. Foi elaborado modelo matemático para explicar o efeito da biodiversidade na transmissão de plasmódios. Resultados - As pessoas estão mais expostas às picadas de Ae. serratus, Ae. scapularis e Ps. ferox em áreas mais quentes e chuvosas. A correlação entre An. marajoara e o padrão espacial da malária foi positiva e significativa, enquanto que An. cruzii e An. bellator não foram importantes. Demonstrou-se que o aumento da heterogeneidade espacial está correlacionado, positivamente, com a biodiversidade de mosquitos. Níveis mais elevados de diversidade de mosquitos e de aves e mamíferos foram associados com risco menor de transmissão de plasmódios. Conclusões - A modelagem de distribuição potencial de habitats é uma ferramenta para a vigilância de vetores de arbovírus. Recomenda-se maior atenção ao An. marajoara que poderia ser vetor secundário de plasmódios em áreas abertas, naturais e desmatadas, da Mata Atlântica. A diversidade de plantas aumenta a heterogeneidade espacial e, esta pode ter efeito positivo à biodiversidade de mosquitos. Maiores diversidades de mosquitos, aves e mamíferos poderiam diminuir o número de picadas infectivas de An. cruzii. Pesquisas futuras sobre a epidemiologia dessas doenças deveriam incluir os seguintes temas: mudanças climáticas e arboviroses, heterogeneidade espacial e mosquitos, e biodiversidade e malária / Introduction - Complex interactions are present between biodiversity of mosquitoes (Diptera, Culicidae) and the dynamics of vector-borne arboviruses and malaria-parasites, which are infectious agents that can cause diseases in humans and other animals. Objectives - to apply habitat-suitability modelling for arboviral and malarial mosquito vectors in Vale do Ribeira, southeastern São Paulo state, sub-region of Serra do Mar of Atlantic Forest. In a local scale of this region, to relate the spatial heterogeneity with biodiversity and the role of this with dynamics of malarial transmission in the Parque Estadual da Ilha do Cardoso. Methods - Potential distribution maps were generated for the vectors of arboviruses, such as Aedes serratus, Aedes scapularis and Psorophora ferox. Distribution maps generated for Anopheles cruzii, Anopheles bellator and Anopheles marajoara were correlated with spatial distribution of human malaria. Regression models were applied to correlate the spatial heterogeneity with biodiversity of mosquitoes. It was elaborated a mathematical model to explain the effect of biodiversity on the transmission of Plasmodium. Results - People are more exposed to bites of Ae. serratus, Ae. scapularis and Ps. ferox in warmer and wetter areas. Correlations between An. marajoara and spatial pattern of malaria were positive and significant, while An. cruzii and An. bellator were not important. Spatial heterogeneity was positively associated with biodiversity of mosquitoes. Higher levels of biodiversity of both mosquitoes and vertebrates (birds and mammals) was associated with low risk of Plasmodium transmission. Conclusions - Habitat-suitability modelling is a tool for the surveillance of vector-borne arboviruses. It is recommended greater attention to An. marajoara which can be a potential secondary vector of Plasmodium parasites in natural or deforested open areas of the Atlantic Forest. Plant diversity could increase spatial heterogeneity which can be associated with higher mosquito diversity. Higher levels of mosquito, avian and mammalian diversities may decrease the number of infectious bites of An. cruzii. Future research on the epidemiology of malaria and arboviruses should include the following combinations of subjects: climate change and arboviruses, mosquito and spatial heterogeneity, and biodiversity and malaria
57

Ross River virus: Ecology, natural history of disease and epidemiology in tropical Queensland

Harley, David Unknown Date (has links)
Introduction This thesis concerns the mosquito-borne arbovirus Ross River (RR) virus. The main objectives were to determine the vector associations, the incidence, costs and natural history of disease, and behavioural and environmental risks for infection in tropical Queensland. 1. Literature review On the basis of the literature review there is strong evidence that Aedes vigilax, Ae. camptorhynchus and Culex annulirostris are important vectors in Australia. Aedes camptorhychus does not occur in Queensland. There is evidence that two peri-domestic container-breeding mosquitoes, Ae. notoscriptus and Ae. aegypti, may be vectors of the virus. The virus has been isolated from many other species but the role of most of these is unclear. It is unclear which vertebrate species are the major reservoirs for human infection. Studies are inconsistent with regard to the prevalence, duration and severity of symptoms and debility during RR virus disease. Nearly all epidemiological studies of RR virus have been descriptive. Therefore one can only surmise what the risks for human infection might be. Epidemiological studies to determine the associations between exposures and risk for disease do not exist. 2. Virus isolation from mosquitoes During 1996-1998 61,619 mosquitoes were processed for virus isolation. Thirty-three isolates of RR virus were made. The largest number (14) were from Ae. carmenti. The minimum infection rate (MIR) per 1,000 was 2.4. Isolates were also made from Ae. imprimens (1 isolate, MIR 10.3), Ae. kochi (2, 0.2), Ae. lineatus (1, 0.2), Ae. notoscriptus (1, 1.6), Ae. vigilax (1, 0.3), Cx. annulirostris (9, 0.3), Cx. vicinus (1, 4.0) and Mansonia septempunctata (3, 5.8). Ross River virus has been isolated from Cx. annulirostris, Ae. vigilax, Ae. notoscriputus and Ae. kochi but not from the other species. Ross River virus was not isolated from Ae. aegypti. Twenty-six isolates came from in or near a colony of 15,000 spectacled flying-fox, Pteropus conspicillatus. The proportion of RR virus positive pools from within 1 km. of this colony was significantly greater than elsewhere for all species combined and for Cx. annulirostris but not for Ae. carmenti. 3. The incidence and costs of Ross River virus disease Unpublished data on National, State and Territory notifications was collected. Crude incidence rates using census figures for denominator data were calculated. The same was done for the areas in which the other studies described in the thesis were carried out. An estimate of the cost of Ross River virus disease in Australia was made. During the period 1991-1998 of the States and Territories the Northern Territory (NT) had the highest and the Australian Capital Territory (ACT) the lowest notification incidences. These were 62-281 and 0-3 per 100,000 per annum, respectively. During this period the notification incidence for Queensland ranged from 70 to 149 per 100,000 per annum. For the local government areas of Cairns and Mareeba, where the majority of cases of RR virus disease for the studies described in this thesis were recruited, the notification incidences were between 74 and 267, and 28 and 200, respectively. On the basis of an average of 4,800 cases per annum in Australia the cost of serological testing and medical consultations were estimated at $443,520 and $105,600. Lost earnings were estimated at $1,798,560. The total cost for medical consultations, serological testing and lost earnings will therefore be over $2 million in an average year. 4. The natural history of Ross River virus disease In 1998 incident cases of RR virus disease were ascertained. Fifty-seven eligible cases were recruited but only 47 could be reviewed on 3 occasions and data on these were analysed. Cases were followed for up to 197 days. Review included history, examination and the administration of the Clinical Health Assessment Questionnaire (CLINHAQ) and Short Form-36 (SF-36) . On initial review the 3 most common symptoms were arthralgia, joint stiffness and myalgia affecting 97.9, 89.4 and 59.6% of cases, respectively. The joint types most commonly affected by pain at the initial review were the ankles, wrists, interphalangeal joints of the fingers, knees and metacarpophalangeal joints. Objective signs of joint inflammation were rare. The prevalence of signs of inflammation decreased and the prevalence of normal joints on examination increased through the reviews. The prevalence of use of NSAIDs decreased through the reviews. On the basis of CLINHAQ items regarding work performance functioning at work improved through the course of the reviews. Linear regression with days since symptom onset as the independent variable was performed for some variables. The 8 dimensions of the SF-36 were standardized to the Queensland population and analyzed longitudinally . Analyses of the CLINHAQ functional disability index (FDI) and the visual analogue scales (VASs) for pain, global severity, fatigue, gastrointestinal complaints and sleep, and the depression and anxiety scales were also performed. The slopes of all fitted regressions except the SF-36 general health dimension were significantly different from zero. All measures of disease severity returned to normal by 8 months from onset, many in a shorter period. 5. Behavioural and environmental risks for infection Fifty-five incident cases of RR virus disease were recruited and formed the basis of a case-control study of behavioural and environmental risks. They were matched to 85 controls. In the year prior to symptom onset the only leisure exposure that significantly altered risk was camping [Odds ratio (OR) = 2.15; 95% confidence interval (CI) = 1.07-4.35]. No peri-domestic activities in the year prior to onset significantly altered disease risk. Leisure exposures were also assessed in a 3-week exposure period ending 4 days prior to symptom onset. None significantly altered risk. No peri-domestic activity in this period significantly altered risk and nor did exposure to vertebrates or mosquitoes. Containers and vegetation around the subject's dwelling did not significantly increase risk. The presence of ice cream containers and buckets was significantly protective when assessed by questionnaire, however this was also assessed by inspection and was found to increase risk though not significantly so. It was concluded that the former finding was due to differential misclassification of exposure status. The premise condition index (PCI) was measured. A low PCI for the subject's house was associated with a significantly increased risk (3-4 relative to 7-9 as reference category: OR = 3.15, 95% CI = 1.07-9.25). Window screening did not alter disease risk and air-conditioning in the house or the bedroom decreased risk but not significantly so. Use of protective measures, except bed nets, in the year prior to onset was found to decrease disease risk. Personal repellents, mosquito coils and citronella candles significantly decreased risk. A dose response was shown for the number of protective measures from personal repellents, aerosol and surface sprays, mosquito coils, citronella candles and mosquito "zappers" used in the year prior to symptom onset. Pet ownership and proximity of dwelling to horses did not significantly alter risk. A preference for light coloured clothing was significantly protective (0.37, 0.15-0.89). Stratification by gender, date of symptom onset and geographical area was performed. Stratification by geographical area included a coastal and tablelands stratum. There were differences between the stratum-specific odds ratios for camping in the year prior to symptom onset, the presence of bromeliads in the subject's garden and a preference for light coloured clothing. Multivariate analysis demonstrated confounding by use of personal repellents, mosquito coils and citronella candles. When modeled together these were found to cause confounding among themselves. They also caused significant confounding of camping, outdoor work and the presence of banana trees in the subject's yard. Multivariate analysis of the association between PCI and disease risk failed to demonstrate confounding by use of protective measures or time between symptom onset and review. 6. Synthesis and conclusions The three research Chapters form a coherent body of public health research on the epidemiology (Chapters 5 and 6) and ecology (Chapters 4 and 7) of RR virus, and the natural history of RR virus disease (Chapter 6) in tropical Queensland. Conclusions are drawn from the research in the thesis. A set of priorities for future public health research on RR virus is suggested, and a pilot control program for Ross River virus disease in tropical Queensland is recommended.
58

Biodiversidade de Culicidae e sua interação com arboviroses e malária na Mata Atlântica / Biodiversity of Culicidae and its interaction with arboviruses and malaria in the Atlantic Forest

Gabriel Zorello Laporta 24 April 2012 (has links)
Introdução - Interações complexas estão presentes entre a biodiversidade de mosquitos (Diptera, Culicidae) e as dinâmicas de transmissão de arbovírus e plasmódios que são agentes infecciosos que podem causar moléstias em humanos e outros animais. Objetivos - Aplicar método de distribuição potencial de habitats para mosquitos vetores de arbovírus e de plasmódios no Vale do Ribeira, sudeste do Estado de São Paulo, sub-região Serra do Mar da Mata Atlântica. Em escala local nessa região, relacionar a heterogeneidade espacial com a biodiversidade e esta com a dinâmica de transmissão de malária no Parque Estadual da Ilha do Cardoso. Métodos - Foram elaborados mapas de distribuição espacial dos vetores de arbovírus: Aedes serratus, Aedes scapularis e Psorophora ferox. Os mapas gerados para Anopheles cruzii, Anopheles bellator e Anopheles marajoara foram correlacionados com a distribuição espacial de malária. As correlações entre heterogeneidade espacial e biodiversidade de mosquitos foram estabelecidas com o emprego de modelos estatísticos de regressão. Foi elaborado modelo matemático para explicar o efeito da biodiversidade na transmissão de plasmódios. Resultados - As pessoas estão mais expostas às picadas de Ae. serratus, Ae. scapularis e Ps. ferox em áreas mais quentes e chuvosas. A correlação entre An. marajoara e o padrão espacial da malária foi positiva e significativa, enquanto que An. cruzii e An. bellator não foram importantes. Demonstrou-se que o aumento da heterogeneidade espacial está correlacionado, positivamente, com a biodiversidade de mosquitos. Níveis mais elevados de diversidade de mosquitos e de aves e mamíferos foram associados com risco menor de transmissão de plasmódios. Conclusões - A modelagem de distribuição potencial de habitats é uma ferramenta para a vigilância de vetores de arbovírus. Recomenda-se maior atenção ao An. marajoara que poderia ser vetor secundário de plasmódios em áreas abertas, naturais e desmatadas, da Mata Atlântica. A diversidade de plantas aumenta a heterogeneidade espacial e, esta pode ter efeito positivo à biodiversidade de mosquitos. Maiores diversidades de mosquitos, aves e mamíferos poderiam diminuir o número de picadas infectivas de An. cruzii. Pesquisas futuras sobre a epidemiologia dessas doenças deveriam incluir os seguintes temas: mudanças climáticas e arboviroses, heterogeneidade espacial e mosquitos, e biodiversidade e malária / Introduction - Complex interactions are present between biodiversity of mosquitoes (Diptera, Culicidae) and the dynamics of vector-borne arboviruses and malaria-parasites, which are infectious agents that can cause diseases in humans and other animals. Objectives - to apply habitat-suitability modelling for arboviral and malarial mosquito vectors in Vale do Ribeira, southeastern São Paulo state, sub-region of Serra do Mar of Atlantic Forest. In a local scale of this region, to relate the spatial heterogeneity with biodiversity and the role of this with dynamics of malarial transmission in the Parque Estadual da Ilha do Cardoso. Methods - Potential distribution maps were generated for the vectors of arboviruses, such as Aedes serratus, Aedes scapularis and Psorophora ferox. Distribution maps generated for Anopheles cruzii, Anopheles bellator and Anopheles marajoara were correlated with spatial distribution of human malaria. Regression models were applied to correlate the spatial heterogeneity with biodiversity of mosquitoes. It was elaborated a mathematical model to explain the effect of biodiversity on the transmission of Plasmodium. Results - People are more exposed to bites of Ae. serratus, Ae. scapularis and Ps. ferox in warmer and wetter areas. Correlations between An. marajoara and spatial pattern of malaria were positive and significant, while An. cruzii and An. bellator were not important. Spatial heterogeneity was positively associated with biodiversity of mosquitoes. Higher levels of biodiversity of both mosquitoes and vertebrates (birds and mammals) was associated with low risk of Plasmodium transmission. Conclusions - Habitat-suitability modelling is a tool for the surveillance of vector-borne arboviruses. It is recommended greater attention to An. marajoara which can be a potential secondary vector of Plasmodium parasites in natural or deforested open areas of the Atlantic Forest. Plant diversity could increase spatial heterogeneity which can be associated with higher mosquito diversity. Higher levels of mosquito, avian and mammalian diversities may decrease the number of infectious bites of An. cruzii. Future research on the epidemiology of malaria and arboviruses should include the following combinations of subjects: climate change and arboviruses, mosquito and spatial heterogeneity, and biodiversity and malaria
59

Perfil sorológico por inibição da hemaglutinação para arboviroses em residentes \"Ribeirinhos\" da região Amazônica e \"rurais\" do sudeste brasileiro. / Serological survey for Arboviruses by hemagglutination inhibition in Residents of Amazon region and country people in Southeastern of Brazil.

Fábio Carmona de Jesus Maués 07 December 2010 (has links)
Neste trabalho foi feito uma investigação sorológica em moradores na região amazônica e moradores rurais do sudeste brasileiro, através do teste de inibição da hemaglutinação (HI) para a cepa vacinal da Febre Amarela mais 17 sorotipos diferentes de arbovírus, sendo quatro do gênero Alphavirus (ALP), nove do gênero Flavivirus (FLA) e cinco do gênero Orthobunyavirus (ORT), para verificar qual desses vírus estão circulando nessas regiões. Os resultados do HI foram divididos em quatro áreas: na cidade Machadinho dOeste (Rondônia) (N=285) tivemos para ALP=50 (17,54%), FLA=270 (94,74%), ORT=58 (20,35%) e negativos (NEG)=12 (4,20%). Nas pessoas que moram ao longo do Rio Machado (Rondônia) (N=343) tivemos ALP=99 (28,86%), FLA=229 (66,76%), ORT=41 (11,95%) e NEG=93 (27,10%). Na cidade Teodoro Sampaio (São Paulo) (N=78) tivemos FLA=55 (70,51%) e NEG=23 (29,5%). Na cidade Jacupiranga (São Paulo) (N=149) tivemos ALP=7 (4,7%), FLA=50 (33,56%), ORT=20 (13,42%) e NEG=84 (56,4%). Concluímos que os resultados obtidos sugerem a circulação desses vírus nas regiões estudadas. / In this work we performed a serological investigation in residents of Amazon region and country people who lives in Southeastern of Brazil, by hemagglutination inhibition (HI) for Yellow fever vaccine and 17 different serotype of arboviruses: four from the genus Alphavirus (ALP), nine from the genus Flavivirus (FLA), and five from the genus Orthobunyavirus (ORT), to try to ascertain which of these arboviruses are circulating in these areas. The results of HI were divided into four areas: In Machadinho dOeste city (Rondônia) (N=285) we had to ALP=50 (17,54%), FLA=270 (94,74%), ORT=58 (20,35%) and negatives (NEG)=12 (4,20%). In people who live along the Machado River (Rondônia) (N=343) we had to ALP=99 (28,86%), FLA=229 (66,76%), ORT=41 (11,95%) and NEG=93 (27,10%). In Teodoro Sampaio City (São Paulo) (N=78) we had to FLA=55 (70,51%) and NEG=23 (29,5%). In Jacupiranga City (São Paulo) (N=149) we had to ALP=7 (4,70%), FLA=50 (33,56%), ORT=20 (13,42%) and NEG=84 (56,4%). In conclusion, the obtained data suggest the circulation of these viruses in these regions.
60

Safety and Stability of Samples Stored on Filter Paper for Molecular Arbovirus Diagnosis

Bringeland, Emelie January 2021 (has links)
Expanding urbanization, climate change, and population growth contribute to increased transmission and spread of arthropod-borne viruses (arboviruses), many of which cause severe disease in humans. Pathogenic arboviruses include dengue, Zika, tick-borne encephalitis, and sindbis viruses, which together threaten more than half the global population. Thus, there is a constant need for safe, specific, and sensitive molecular tests to identify early-stage infections for accurate diagnosis and molecular epidemiological data for disease prevention and control. The study tested the biosafety of using FTA™ cards when working with pathogenic arboviruses by conducting an infectivity assay using sindbis virus. Conditions for RNA extraction and storage of arboviruses on FTA were analyzed by measuring viral RNA (vRNA) stability using a SYBR-Green, Pan-Flavi RT-qPCR method composed of degenerate primers able to detect a variety of flaviviruses. Data from a Pan-Flavi RT-qPCR study comprising of 222 clinical blood and serum samples collected from a 2018 dengue virus outbreak in Hanoi (Vietnam) was analyzed to establish applicability of FTA for molecular epidemiology and diagnosis. Results showed that sindbis virus infectivity was inhibited by FTA-adsorption. FTA-adsorbed arboviruses were extracted with the highest yield using Trizol extraction and were preserved at storage at 4-20ºC for up to 30 days. The results showed that clinical blood samples acquired higher yields of vRNA for molecular testing than serum samples and that it may be possible to perform sequencing for genomic analysis. The study suggests that FTA cards may facilitate the storage and transportation of adsorbed arboviruses for downstream molecular epidemiological and diagnostic tests.

Page generated in 0.0488 seconds