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Delogu, Ilenia. "Virus chikungunya et traitement antiviral". Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX20668/document.
Pełny tekst źródłaThe Alphavirus RNA viruses are enveloped with a diameter of 70 nm, icosahedral structure with symmetry of type T = 4 (Choi et al. 1991; Cheng et al. 1995; Garoff et al. 2004). These viruses, whose distribution is worldwide, can infect a wide variety of vertebrates (mammals, birds, fish). These viruses are arboviruses, is à_dire viruses transmitted by arthropods. In the case of Alphavirus, the vectorization is done by mosquitoes from several species.To date, 29 species of Alphavirus have been identified, including at least six are pathogenic for humans. In humans, some are responsible for Alphavirus encephalitis, arthritis, fever, rash and can be fatal (Thiruvengadam et al. 1965; Pialoux et al. 2006).The first was isolated Alphavirus Equine Encephalitis West (Weeve) in 1930 (Meyer et al. 1931). The encephalitis virus Eastern (VEEV) and virus Venezuelan equine encephalitis (VEEV) were isolated respectively in 1933 and 1938 (Gibbs EP. 1976; Beck et al. 1938; Kubes et al. 1939 ). Sindbis virus isolated in Egypt in 1952 (Taylor et al. 1955), was the first Alphavirus responsible for arthritis to be isolated. The demonstration of the existence of CHIKV in Tanzania will be 1952 (Robinson 1955) (Lumsden 1955). Then follow the discoveries of all other Alphavirus. The South Elephent Seal virus (SESV), identified in 2000 on the Australian island of Macquarie is now the last Alphavirus discovered. The phylogenetic strains of Chikungunya can identify different clades for strains of East African, Western or Asian, and phylogenetic analysis is very close O'Nyong-Nyong (Powers and al. 2000), The sequencing of different isolates of the epidemic of 2005, helped to highlight some of them a mutation in the envelope glycoprotein more specifically in E1 (Schuffenecker et al. 2006). This mutation causes the substitution of an arginine at position 226 instead of valine (A226V), is a key element in determining the choice of a new vector for the transmission or Aedes albopictus (which transmits on the island of La meeting) with respect to the vector Aedes aegypti (Tsetsarkin et al. 2007). This mutation was later also found in India in 2007. (Arankalle et al. 2007; Kumar et al. 2008; Santhosh et al. 2008).The classic presentation often begins with sudden onset of high fever (40°C) for 3 / 10 days intermittent chills (Deller and al.1967). Fever is, in some cases, bi-phasic, that is to say, it decreases during a day or two before rising sharply. It is usually followed by erythema, pain or stiffness of muscle pain and muscle aches (Ozden et al. 2007) especially those involving pain in the extremities (wrists, ankles and knuckles) (Robinson 1955; Jadhav et al. 1965; Thiruvengadam et al. 1965). Also headache, rash maculopapular itchy sometimes. The rash affecting the chest and face hands and feet, children were seen eruptions like bullous skin accompanied by a detachment (Talarmin et al. 2007). The evolution of the disease regresses gradually. There is no antiviral therapy effective against CHIKV. Treatment is essentially symptomatic and consists of non-analgesic salicylates, paracetamol and anti-inflammatory drugs. This work consists of two parts: one part on the phylogenetic study of CHIKV and one part of the study of antiviral molecules. [...]
Koga, Rosemary de Carvalho Rocha. "ASPECTOS CLÍNICOS E SOROLÓGICOS DE INDIVÍDUOS COM SINAIS E SINTOMAS DE FEBRE CHIKUNGUNYA". Pontifícia Universidade Católica de Goiás, 2017. http://tede2.pucgoias.edu.br:8080/handle/tede/3664.
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Introduction: Chikungunya fever (FCHIK) is a disease of abrupt onset, transmitted by arthropod mosquitoes intermediate hosts of the Chikungunya virus (CHIKV). The illness has a significant impact on the quality of life of the affected person. Since a disease causes intense and prolonged symptoms of polyarthralgia and myalgia, it requires health care, during a recovery, more than other arboviruses. The objective of this study was to study clinicians and clinicians suggestive of FCHIK, residing in the States of Amapá and Goiás, aiming to correlate the results of laboratory tests with the presented symptomatology. Materials and methods: The study was carried out at the Center for Immunological Studies and Research of the Pontifical Catholic University of Goiás, Goiânia, and in Emergency Care Units in the cities of Macapá, Oiapoque and Santana-AP. The study population consisted of 80 individuals with suspected FCHIK and for investigators of inflammatory markers, the control group consisted of 20 blood samples from healthy donors from Goiana Central de Serologia e Imunohematologia. Viral RNA extraction was performed, followed by RNA detection by Real-Time Polymerase Chain Reaction. In addition to ELISA for detection of IgM and IgG against Chikungunya virus. Participants symptoms were correlated with serology and Creactive protein (CRP), which was evaluated in healthy subjects and in people with FCHIK. Results: No data presented for detection of viral RNA by RT-qPCR for CHIKV, but three samples were positive in this technique for zika virus and one for dengue subtype 1 (DENV1). In an enzyme-linked immunosorbent assay, 26 samples were positive for IgG and 3 for IgM. Regarding the stage of the disease, 10 were in the acute phase, 04 in the subacute phase and 12 in the chronic phase. Correlated the results of the serology with a symptomatology it was observed that the acute phase, all have fever, 90% headache, 70% arthralgia and 60% edema. (100%), myalgia and edema (75%). (100%), arthralgia (92%) and myalgia (75%). When comparing participants with negative serology, n = 54, the most prevalent symptoms were rash, headache, fever, and arthralgia. The CRP levels in individuals infected with more than four symptoms were higher when compared with healthy individuals. Conclusion: The study focused on people with a clinical picture characteristic of FCHIK. The most common symptom in the three phases presented for arthralgia, followed by edema and myalgia, a fever was frequent only in the acute phase. All participants were negative in the evaluation of viral RNA by RT-qPCR for CHIKV, for the virus has a short duration in the body, and this methodology is limited to the time of symptom onset and sample collection, DENV and ZIKV. IG G. Those with negative serology for CHIKV, despite taking into account the joints, symptoms common to other arboviruses. CRP levels have been shown to be high relative to healthy subjects.
Introdução: A Febre Chikungunya (FCHIK) é uma doença de início abrupto, transmitida por mosquitos artrópodes hospedeiros intermediários do vírus Chikungunya (CHIKV). A enfermidade representa um significativo impacto na qualidade de vida da pessoa afetada. Uma vez que a doença causa sintomas intensos e prolongados de poliartralgia e mialgia, requerendo atenção de saúde, durante a recuperação, mais do que outras arboviroses. Objetivou-se estudar aspectos clínicos e sorológicos de indivíduos apresentando quadro clínico sugestivo de FCHIK, residentes nos Estados de Amapá e Goiás, visando correlacionar os resultados de testes laboratoriais com a sintomatologia apresentada. Materiais e métodos: O estudo foi realizado no Núcleo de Estudos e Pesquisa Imunológica da Pontifícia Universidade Católica de Goiás, em Goiânia, e em Unidades de Pronto Atendimento de Saúde das cidades de Macapá, Oiapoque e Santana-AP. A população de estudo foi constituída de 80 indivíduos com suspeita de FCHIK e para comparar os marcadores inflamatórios, o grupo controle foi constituído de 20 amostras de sangue de doadores saudáveis da Central Goiana de Sorologia e Imunohematologia. Foi realizada a extração do RNA viral, seguido de detecção do RNA por meio de Reação em Cadeia de Polimerase em Tempo Real. Além de ELISA para detecção de IgM e IgG específicos para o CHIKV. Os sintomas dos participantes foram correlacionados com o resultado da sorologia e da proteína C reativa (PCR), que foi avaliada em indivíduos saudáveis e em pessoas com FCHIK. Resultados: Nenhuma amostra apresentou limiar de detecção do RNA viral por RT-qPCR para CHIKV, porém três amostras foram positivas nessa técnica para vírus zika (ZIKV) e uma para dengue subtipo 1 (DENV1). Em ensaio imunoenzimático, 26 amostras foram positivas para IgG e 3 dessas para IgM. Em relação ao estágio da doença, 10 encontravam-se em fase aguda, 04 em fase subaguda e 12 em fase crônica. Correlacionados os resultados da sorologia com a sintomatologia observou-se que os de fase aguda, todos tiveram febre, 90% cefaleia, 70% artralgia e 60% edema. Enquanto que, os de fase subaguda tiveram: artralgia e cefaleia (100%), mialgia e edema (75%). Os de fase crônica tiveram edema (100%), artralgia (92%) e mialgia (75%). Quando comparados os participantes com sorologia negativa, n=54, os sintomas mais apresentados foram exantema, cefaleia, febre e artralgia. Os níveis de PCR nos indivíduos infectados e que apresentavam mais de quatro sintomas foram maiores quando comparados com indivíduos saudáveis. Conclusão: O estudo focou em pessoas com quadro clínico característico para FCHIK. O sintoma mais comum nas três fases apresentadas foi a artralgia, seguido de edema e mialgia, a febre foi frequente somente na fase aguda. Todos os participantes foram negativos na avaliação do RNA viral por RT-qPCR para CHIKV, pois o vírus tem uma curta duração no organismo, e esta metodologia é limitada ao tempo de início dos sintomas e coleta de amostra, ainda assim foi encontrado RNA viral do DENV e ZIKV. Alguns participantes foram positivos para sorologia IgG. Aqueles com sorologia negativa para CHIKV, apesar de terem dor nas articulações, tinham sintomas comuns a outras arboviroses. Os níveis de PCR demonstraram-se elevados em relação aos indivíduos saudáveis.
Hiroki, Carlos Hiroji. "Papel das Neutrophil Extracellular Traps no controle da infecção por Chikungunya". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/17/17147/tde-01022019-105719/.
Pełny tekst źródłaChikungunya is a reemerging virus which causes a disease characterized by an incapacitanting arthralgia and affects thousands of people. Innate response against this virus is well described by participation of macrophages, dendritic cells and NK cells, however few works demonstrate the roe of neutrophils in this infection. Neutrophils Extracellular Traps are a web of DNA complexed with antimicrobial enzymes which were described for fighting against many pathogens. However, there are no works which demonstrate its relevance in Chikungunya infection. Our objective was to evaluate if there is release of NETs in Chikungunya infection, describe its mechanisms and demonstrate its relevance in vitro and in vivo. We observed that mouse and human neutrophils incubated with Chikungunya are able to produce NETs via Toll-Like 7 and reactive oxygen species production. These NETs were able to capture the virus and inhibit its infection in vitro. Moreover, animals infected with Chikungunya virus and treated with rhDNAse demonstrated higher viral load and are more susceptible to the infection, showing its importance in vivo. Lastly, patients diagnosed during acute infection of Chikungunya infection have high levels of NETs correlated with a high viral load.
MARQUES, Nuno Miguel da Silva. "Dengue e chikungunya: arboviroses emergentes em Angola". Doctoral thesis, Instituto de Higiene e Medicina Tropical, 2017. http://hdl.handle.net/10362/57140.
Pełny tekst źródłaIn recent decades, there has been a reduction in the number of malaria cases in many sub- Saharan African countries. However, the overdiagnosis of malaria in endemic areas is frequent. The clinical relevance of arboviruses in the differential diagnosis of malaria in Angola is unknown. Historically the main arbovirosis described in Angola has been Yellow Fever. However, there was evidence of circulation of other arboviruses such as the Chikungunya virus during the colonial period. After the country's independence, which occurred in 1975, sporadic dengue cases imported from Angola were registered in several countries. Thus, until 2012, the lack of knowledge about the prevalence of arboviruses, such as Dengue and Chikungunya, was a reality. An observational and cross - sectional study was carried out to identify the presence of Dengue virus and Chikungunya virus. Patients with febrile syndrome (body temperature at admission ≥37.5 ° C and / or history of fever) and clinically compatible with malaria were included. Rapid diagnostic tests (TDR) [SD BIOLINE®], which are immunochromatographic assays for the detection of: Ag NS1 and IgG / IgM antibodies against Dengue virus have been applied; Ig M against the Chikungunya virus; Ag HRPII- P.f and pLDH-P.v from Plasmodium spp. Biological samples were also collected for molecular biology techniques (PCR or RT-PCR) for Plasmodium spp., Dengue and Chikungunya. The study was conducted in two phases, the first from February to April 2012 in Huambo province and the second from May to June 2015 in Benguela province, with a total of 542 patients. In the first phase 242 patients were included, mostly female (59.9%). The average age was 16 years. The most common symptoms were respiratory such as cough (60.7%) and nasal discharge (48.3%) followed by painful complaints, headache (40.1%), abdominal pain (36.4%), arthralgia (33 , 9%) and myalgias (30.6%). The rates of positive TDR were as follows: malaria (2.1%), Chikungunya (1.7%) and Dengue (0.8%). There was a case of concomitant positivity for Dengue (Ag NS1 +) and Chikungunya. In the second phase 300 patients were included, also mostly female (61%). The average age was 19 years. The most frequent clinic complaints were headaches (53%), myalgias (45%), arthralgia (43.3%), abdominal pains (38.3%) followed by cough (26.3%) and runny nose (16.3%). The rates of positive TDR were as follows: malaria (36.7%), Chikungunya (18.3%) and Dengue fever (3.3%). There were 28 cases of concomitant positivity for malaria and Chikungunya and 4 cases for malaria and Dengue (1 with Ag NS1 + and 3 with IgM +). In this second phase a Chikungunya genomic sequence was also identified by RT-PCR which revealed a high identity with a circulating strain in Cameroon in 2006. This study was relevant for the recent investigation of arbovirus in Angola, documenting its circulation, as well as for allowing for the first time the large-scale application of TDR to Dengue and Chikungunya in this country.
Thiberville, Simon-Djamel. "Investigations épidémiologiques, cliniques et thérapeutiques du chikungunya". Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM5016.
Pełny tekst źródłaChikungunya virus (CHIKV) is an arthropod-borne virus transmitted by Aedes mosquitoes that cause debilitating arthralgia and possible chronic rheumatism. In the first part we describe the clinical, biological and virological presentation of outpatients with chikungunya disease (CHIK) from the acute stage to the chronic stage at day 300, during the outbreak in the Reunion Island in 2006. We elaborated scores for CHIK diagnosis and we also analysed the intra-host genetic diversity.To complete our first results, we investigated a CHIKV outbreak, which occurred in the Republic of Congo in 2011. The clinical presentation was similar to the first description of the Reunion island outbreak. We assessed the clinical score which appeared to be unusable at the individual level but was still relevant to follow the epidemic curve. This work was completed by seroprevalence and phylogenetic analyses.The last study presented in this thesis focused on the use of chloroquine during the acute stage of CHIK in a non-human primate (NHP) model (prophylactic use) and during a clinical trial (therapeutic use). The main effect of chloroquine treatment at the acute stage of CHIK appeared to be related to its immuno-modulatory action; in prophylactic taking, chloroquine exacerbated acute symptoms while treatment during the early stages of the disease increased the risk of acquiring chronic arthralgia.In conclusion, we provide a detailed description of CHIK outpatients and identify risk factors for the chronic stage of the disease. We propose tentative diagnostic scores and we firmly establish that the use of chloroquine at the acute phase of CHIK is contraindicated
Enguehard, Margot. "Interaction between chikungunya and dengue viruses during co-infection in Aedes mosquito cells and in Aedes aegypti mosquito". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1161/document.
Pełny tekst źródłaEmergence and geographical extension of dengue (DENV), Zika (ZIKV) and chikungunya (CHIKV) viruses increase simultaneous outbreak in an increasing number of countries. To date, no vaccine or cure have yet been developed against these diseases those cause a tremendous impact on human health and in the economy worldwide. During recent simultaneous outbreaks, up to 12% of patients have been diagnosed to be co-infected by CHIKV and DENV. In addition, it was shown that the mosquitoes Aedes albopictus could carry and transmit simultaneously CHIKV and DENV. However, the pathology, as well as the epidemiology of a pathogen, relies on the interactions between several infectious agents present within an organism or a community in the environment. It is crucial to consider to which extent a host infected by a first microorganism is modified and whether its reaction to the infection by a second microorganism is consequently altered. However, there is no extensive report of Alphavirus-Flavivirus or Flavivirus- Flavivirus interactions. Our global objective is to characterize these co-infections in both mosquitoes and humans, at the cell and molecular level. To this aim, we started this project by performing sequential co- infection in different cell lines from Aedes albopictus and Aedes aegypti. We found that the permissiveness and production of DENV is enhanced in presence of CHIKV. On the contrary, there is no effect of DENV pre-infection on subsequent CHIKV co-infection. We generalized the synergistic phenomena and we showed that CHIKV pre-infection also increased the infection by DENV-1, DENV-3 and DENV-4, but also by two others re-emerging Flaviviruses, the Yellow Fever Virus (YFV), and the Zika Virus (ZIKV). Remarkably, we succeeded to establish a mosquito model of co-infection of Aedes aegypti mosquito after by different two feedings at 4 days interval. Using this sequential co-infection, we were able to show that a pre-infection of Aedes aegypti by CHIKV increase the level of DENV-2 RNA in salivary glands compare to mono-infected mosquitos. This phenotype is reminiscent of the phenotype we observed in vitro during successive infections. Altogether, our study paves the way to the characterization of molecular interaction between Flaviviruses and Alphaviruses in mosquito in vitro and in vivo. This study can be crucial for a better understanding of disease and epidemiology during simultaneous outbreaks
VENTORIM, D. P. "DIVERSIDADE Genética de Chikungunya no Estado do Espírito Santo". Universidade Federal do Espírito Santo, 2018. http://repositorio.ufes.br/handle/10/7120.
Pełny tekst źródłaA febre chikungunya é uma arbovirose altamente debilitante, causada pelo vírus chikungunya, o qual é transmitido pela picada de mosquitos do gênero Aedes. Em 2014 foram registrados os primeiros casos da doença no Brasil, sendo constatada a presença dos genótipos asiático e Leste/Centro/Sul africano do vírus. No final de 2015, pela primeira vez, foram reportados casos no Espírito Santo (ES) e entre 2016-2017 o estado enfrentou um surto da doença. Diante disso, nós, juntamente à Secretaria Estadual de Saúde/ES e ao Laboratório Central/ES objetivamos identificar qual linhagem do vírus circula no ES; analisar características genéticas virais nas amostras estudadas e levantar dados epidemiológicos sobre a doença no estado. As amostras do estudo foram provenientes do Laboratório Central/ES e referentes ao período de março/2016 - dezembro/2017. O diagnóstico viral foi realizado por sorologia ou por técnicas moleculares. Vinte e sete amostras (diagnosticadas molecularmente) foram utilizadas na amplificação parcial e sequenciamento de dois genes codificantes de proteínas do envelope viral, E1 e E2. Seis dessas amostras foram utilizadas nas análises filogenéticas. Os resultados epidemiológicos demonstraram que no período do estudo foram reportados 2.021 casos suspeitos da febre chikungunya, sendo 412 (20,38%) confirmados. Além disso, a distribuição geográfica desses casos constatou que Vitória e Vila Velha representaram mais de 50% de todos os casos do estado. Os achados mostraram que a frequência da infecção pelo vírus chikungunya, em relação ao número de amostras referenciadas ao Laboratório Central/ES, pode ser considerada baixa. No entanto, constatou-se que a doença apresenta relevância epidemiológica e grande distribuição no estado. Os resultados filogenéticos evidenciaram que o vírus circulante pertence à linhagem Leste/Centro/Sul africana, a qual também foi constatada em diversos surtos na Europa, África e Ásia. Além disso, a caracterização molecular dos fragmentos das proteínas E1 e E2 não mostraram a presença das mutações adaptativas E1-K211E; E1-A226V; E2-L210Q e E2-I211T. Esse resultado permite sugerir que o vírus circulante no ES apresenta um potencial de disseminação menor em comparação aos vírus circulantes em grandes epidemias mundiais recentes. Devido à falta de uma vacina e à dificuldade no controle populacional do mosquito vetor, estudos sobre a diversidade genética como este tornam-se alternativas viáveis em busca de melhor entendimento e controle da febre chikungunya no Brasil e, especificamente, no ES.
Dagley, Ashley L. "Amelioration of Chikungunya through Inhibition of the Inflammatory Response". DigitalCommons@USU, 2016. https://digitalcommons.usu.edu/etd/4996.
Pełny tekst źródłaYapa, Badal Madiththegedara Chamini Randika Wimalasiri. "Chikungunya virus transmission dynamics and immune responses in mosquitoes". Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/206132/1/Badal%20Madiththegedara%20Chamini%20Randika%20Yapa%20Thesis.pdf.
Pełny tekst źródłaVega, Rua Anubis. "Émergence du virus chikungunya en Amérique et en Europe". Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066197/document.
Pełny tekst źródłaChikungunya virus (CHIKV), transmitted mainly by the mosquitoes Aedes aegypti and Aedes albopictus, is a major public health problem. Since 2004, CHIKV epidemics have been reported in Africa, Asia, the Indian Ocean Islands, and Europe. Only the Americas seemed spared despite high densities of mosquitoes and multiple introductions of the virus to the continent by travelers returning from countries where CHIKV was circulating. We have assessed the risk of CHIKV emergence in the Americas by evaluating the vector competence of 35 local populations of Ae. aegypti and Ae. albopictus infected with different strains of CHIKV. These populations were shown to be susceptible to CHIKV infection, highlighting the predominant role of salivary glands as a "filter" of transmission. Genotyping of Ae. albopictus from the Americas using microsatellites allowed the identification of a genetic cluster of populations characterized by a low transmission of CHIKV strains of the East-Central-South-African genotype. In October 2013, Asian strains of CHIKV began circulating in the Caribbean. Thus, we evaluated the susceptibility of 11 populations of Ae. aegypti and Ae. albopictus to the Asian CHIKV genotype and showed that the two species were sufficiently competent to ensure dissemination of the virus throughout the continent. Furthermore, we showed that Ae. albopictus was likely to facilitate the spread of CHIKV to Europe. However, the vector competence of French Ae. albopictus to the Asian CHIKV genotype was negatively affected by temperatures lower than those usually found in tropical countries
Vega, Rua Anubis. "Émergence du virus chikungunya en Amérique et en Europe". Electronic Thesis or Diss., Paris 6, 2015. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2015PA066197.pdf.
Pełny tekst źródłaChikungunya virus (CHIKV), transmitted mainly by the mosquitoes Aedes aegypti and Aedes albopictus, is a major public health problem. Since 2004, CHIKV epidemics have been reported in Africa, Asia, the Indian Ocean Islands, and Europe. Only the Americas seemed spared despite high densities of mosquitoes and multiple introductions of the virus to the continent by travelers returning from countries where CHIKV was circulating. We have assessed the risk of CHIKV emergence in the Americas by evaluating the vector competence of 35 local populations of Ae. aegypti and Ae. albopictus infected with different strains of CHIKV. These populations were shown to be susceptible to CHIKV infection, highlighting the predominant role of salivary glands as a "filter" of transmission. Genotyping of Ae. albopictus from the Americas using microsatellites allowed the identification of a genetic cluster of populations characterized by a low transmission of CHIKV strains of the East-Central-South-African genotype. In October 2013, Asian strains of CHIKV began circulating in the Caribbean. Thus, we evaluated the susceptibility of 11 populations of Ae. aegypti and Ae. albopictus to the Asian CHIKV genotype and showed that the two species were sufficiently competent to ensure dissemination of the virus throughout the continent. Furthermore, we showed that Ae. albopictus was likely to facilitate the spread of CHIKV to Europe. However, the vector competence of French Ae. albopictus to the Asian CHIKV genotype was negatively affected by temperatures lower than those usually found in tropical countries
Punelle, Clément Pasquier Christophe. "Implication de la faune domestique et sauvage dans l'épidémie de Chikungunya dans les îles de l'Océan Indien". [S.l.] : [s.n.], 2008. http://oatao.univ-toulouse.fr/2166/1/celdran_2166.pdf.
Pełny tekst źródłaPinto, Tatiana Priscilla Coelho. "Expressão e purificação da proteína E3 do vírus chikungunya (CHIKV)". Master's thesis, Expressão e purificação da proteína E3 do vírus chikungunya (CHIKV), 2013. http://hdl.handle.net/10362/10528.
Pełny tekst źródłaVELEZ, André Filipe Marques. "Produção de virus like particles (VLPs) do vírus chikungunya (CHIKV)". Master's thesis, Instituto de Higiene e Medicina Tropical, 2012. http://hdl.handle.net/10362/19201.
Pełny tekst źródłaChikungunya vírus (CHIKV) is a mosquito-transmitted alphavirus that causes an acute infection in humans, characterized by fever, myalgia and painful invalidating poly-arthralgia that may last for months. CHIKV was first reported in Tanzania in 1952 and became endemic in Africa, India and South-East Asia. Since 2005, outbreaks in the Indian Ocean and Asian continent reached an atypical magnitude and virulence, with many thousands of people infected and associated fatalities. Travelling and changing patterns of vector distribution and abundance due to climatic changes, make CHIKV a global threat without effective control strategies. One approach to reduce the CHIKV burden is the development of a vaccine. Virus-like particles are a safe and highly effective class of recombinant vaccines that mimic the overall structure of virus particles. Accordingly, we aimed to obtain a recombinant vector, able to induce CHIKV VLPs upon cell transfection, as a source of CHIKV structural genes to construct a recombinant baculovirus for VLP production in insect cells. CHIKV structural ORF was amplified by RT-PCR as a SacI-NotI fragment, and cloned into the mammalian expression vector pLEXm downstream from the strong chick beta actin promoter. Several clones with the correct insert size were obtained and transfected into HEK 293T cells using polyethylenimine as the transfection reagent. Five recombinant vectors were shown to express CHIKV proteins by immunofluorescence (IF) and Western blotting (WB) with a polyclonal serum against CHIKV. One clone, with high levels of IF labelling, demonstrated a truncated viral polyprotein of 26 kDa on WB while three others, with a lower IF signal, originated low levels of viral envelope glycoproteins correctly processed. Cells transfected with clone pLCHIKS67 showed IF staining and viral glycoprotein WB pattern similar with those of cells infected with CHIKV. Precipitation with PEG 8000 of clarified cell culture medium from pLCHIKS67 transfected cells and from CHIKV infected cells generated pellets with an identical content of viral glycoproteins on WB, strongly indicating that pLCHIKS67 transfected cells express CHIKV structural proteins that are assembled into VLPs. Transmission electron microscopy of transfected cells demonstrated cytoplasmic membrane rearrangements similar to the vesicle arrays observed in CHIKV infected cells and confirmed the assembly of VLPs with size and morphology similar to the virus particles produced in infected cells. Therefore, pLCHIKS67 will be used as a source of CHIKV structural genes for construction of recombinant baculoviruses and VLP production in insect cells, well-known for allowing high yields of recombinant protein expression.
Silva, Filho Edson Meneses da. "Neuromodula??o para o tratamento das artralgias decorrentes da chikungunya". PROGRAMA DE P?S-GRADUA??O EM CI?NCIAS DA REABILITA??O, 2017. https://repositorio.ufrn.br/jspui/handle/123456789/24763.
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O v?rus da Chikungunya (CHIK) ? uma epidemia no Brasil com 170.000 casos no primeiro semestre de 2016. Mais de 60% dos pacientes apresentam rea??o e remiss?o de artralgia cr?nica com dor debilitante que dura anos. N?o existem agentes terap?uticos espec?ficos para tratar e reabilitar pessoas infectadas com CHIK. Dor persistente pode levar ? incapacita??o exigindo tratamento farmacol?gico de longo prazo. Os avan?os nos tratamentos n?o farmacol?gicos s?o necess?rios para promover o al?vio da dor sem efeitos colaterais e restaurar a funcionalidade. Aqui, n?s demonstramos que a Estimula??o Transcraniana com Corrente Cont?nua (ETCC) sobre o c?rtex motor prim?rio reduz significativamente a dor na fase cr?nica da CHIK. Nossos achados sugerem que a ETCC pode ser uma terapia eficaz, barata e implant?vel em ?reas que n?o possuem recursos e que apresentam um grande n?mero de pacientes com dor cr?nica persistente gerada pela CHIK.
The Chikungunya (CHIK) virus is epidemic in Brazil, with 170,000 cases in the first half of 2016. More than 60% of patients present relapsing and remitting chronic arthralgia with debilitating pain lasting years. There are no specific therapeutic agents to treat and rehabilitee infected persons with CHIK. Persistent pain can lead to incapacitation, requiring long-term pharmacological treatment. Advances in non-pharmacological treatments are necessary to promote pain relief without side effects and to restore functionality. Here, we demonstrate that the transcranial direct current stimulation (tDCS) across the primary motor cortex significantly reduces pain in the chronic phase of CHIK. Our findings suggest tDCS could be an effective, inexpensive and deployable therapy to areas lacking resources with a great number of patients with chronic CHIK persistent pain.
Bouraï, Mehdi. "Caractérisation d'un interactome virus-hôte : l'exemple du virus du Chikungunya". Paris 7, 2011. http://www.theses.fr/2011PA077183.
Pełny tekst źródłaThe lifting of many technological barriers in recent years has allowed the development of « functional genomics », an innovative systemic approach to molecular and cell biology. Viruses, being intracellular parasites, interact with several components of the cell to replicate. Thus, defining and improving our knowledge of the interactions between viral and cellular proteins ensures a better understanding of the viral replication cycle and pathogenesis and opens the pathway to new therapeutic approaches. In my thesis, I defined the interaction map, or interactome, of the chikungunya virus (CHIKV), a virus whose interactions with the cell at the molecular level have been poorly understood. For this, I performed high throughput two-hybrid approaches in yeast (HT-Y2H) and validations in mammalian cells (including protein complementation assay technique or PCA). We screened all the CHIKV mature proteins across three different human cDNA libraries and a normalized 12,000 human full-length open reading frames (ORF) library. We identified 22 interactions, the majority of which involve non-structural protein 2 (nsP2) of CHIKV. Among the identified cellular interactors, we showed the important role of hnRNP-K (heterogeneous nuclear ribonucleoprotein K) and ubiquilin 4 in virus replication in vitro. Furthermore, we demonstrated the involvement of the TTC7B protein (tétratricopeptide 7B) in the transcriptional inhibition activity induced by the nsP2 protein of CHIKV. Such techniques conducted in the laboratory also allowed me to participate in thé charaterization of three virus-host interactions identified by a fellow PhD student and contribute to researching the replication of measles virus (MV) and type 3 human parainfluenza virus (hPIV3). In particular, I was able to accurately map the peptide domains involved in these interactions, using a technique adapted from Y2H. This work has allowed me to not only understand the current techniques for defining virus-host interactomes and consequently produce a map of virus-host interactions for CHIKV, but also to shed some light on the viral mechanisms involved in the replication cycle and the pathogenesis of this virus
Mohamed, Ali Souand. "Le virus Chikungunya : mécanismes évolutifs et outils de génétique inverse". Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0665/document.
Pełny tekst źródłaEmergence of some pathogenic arboviruses is a major public health concern. The Chikungunya virus (CHIKV) is a typical example of re-emerging pathogen since it recently caused large outbreaks in human population, adapted to a new vector and spread to new areas. This emergence is the consequence of phenomena related to the high genomic plasticity of CHIKV. Understanding the mechanisms of adaptation of arboviruses could help to better control these viral pathogens. The first part of this thesis presents a study of the mutations associated with long-term replication of CHIKV in mammalian and mosquito cells. Our results revealed different evolutionary patterns in mammalian and mosquito cells highlighting the difficulties encountered by arboviruses related to host alternation during their natural cycle. The second part of this thesis deals with the homologous recombination, an important process that play a role in the evolution of RNA viruses. Working with the CHIKV, we did not detect any recombination events between attenuated infectious viruses. However, we detected viruses harboring large genomic deletion that could help an attenuated virus by trans-complementation. The last part of this thesis focused on reverse genetic methods that give the possibility to rescue viruses and can be used to study mutations associated with emergence phenomena. Using the CHIKV as a model, we compared the genotype and the phenotype of viruses generated using different reverse genetic methods in cellulo and in vivo using Aedes mosquitos. Our results showed that the choice of the method influenced the genetic diversity of viral populations but whatever the method used, the phenotype was similar
Cresson, Marie. "Study of chikungunya virus entry and host response to infection". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1050.
Pełny tekst źródłaAlphaviruses are a group of enveloped, positive-sense RNA viruses which are distributed almost worldwide and are responsible for a considerable number of human and animal diseases. Among these viruses, the Chikungunya virus (CHIKV) has recently re-emerged and caused several outbreaks on all continents in the past decade. Despite many studies, molecular mechanisms of chikungunya virus replication and virus-host interactions remain poorly understood. The aim of my project was to better understand and characterize the CHIKV entry and the host factors involved during replication steps in mammals. Several different approaches have been used in this work. As a first step, we have demonstrated a decrease of CHIKV infection after iron treatment in form of ferric ammonium citrate and we have studied the potential role in viral entry of NRAMP2 and TFRC, two proteins involved in iron transport and known receptors for other viruses. On the other hand, we have also focused on two proteins, CD46 and TM9SF2, identified through an RNAi screen in collaboration, in order to determine if they are required as entry factors for chikungunya virus. In a last axis, we have set up and carried out a genome-wide loss of function screen with the CRISPR/Cas9 technology in order to identify host factors important for chikungunya virus entry, replication or virus-induced cell death. Although it appears that screen conditions should be optimized, we have identified potential candidates required for CHIKV infection and we are currently testing them
White, Timothy William. "Identifying drivers of Chikungunya virus transmission in the Asia-Pacific". Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/225936/1/Timothy_White_Thesis.pdf.
Pełny tekst źródłaSoumahoro, Agbo Man-Koumba. "Epidémie de Chikungunya à l'île de La Réunion : aspects médicaux et économiques". Paris 6, 2010. http://www.theses.fr/2010PA066244.
Pełny tekst źródłaSolignat, Maxime. "Cycle de réplication du virus Chikungunya chez l'homme et l'Aedes : tropisme cellulaire et mécanisme d'entrée". Montpellier 1, 2009. http://www.theses.fr/2009MON1T007.
Pełny tekst źródłaChikungunya virus (CHIKV) is a mosquitoe transmitted Arbovirus and more particulary by the Aedes mosquitoe genus. This Alphavirus which belongs to the Semliki Forest group was identified like the responsible [i. E. Responsable] agent for the epidemic disease in 2005 and 2006 on the territory of La Reunion and in the Indian Ocean. Whereas this disease was generally regarded as nonfatal, 256 deaths were directly allotted to the virus at the time of the epidemic episode in La Reunion. Although it was isolated in 1952, the CHIKV remains poorly understood and the brutal modifications of the physiopathology of the infection by this virus in La Reunion are unexplained to date. No treatment is available at the present time. Among envelopped viruses, there are various entry pathways in the host cell which are as many targets to inhibit the replicative cycle of these viruses. The main aim of my thesis consisted in characterizing the entry mechanism of CHIKV in human cells and in mosquitoe cells of the Aedes family. Thus, we described for the first time the entry mechanism of CHIKV in these target [i. E. Targets] cells and this, for various viral isolates. More particularly, we highlighted the role of the clathrin mediated endocytic pathway and the endosomes vesicles in these mechanism [i. E. Mechanismes]. Finally, we studied the influence of cellular and molecular interactions between the CHIKV and the endosymbiotic bacteria Wolbachia on viral replication. This obligatory intracellular bacteria which is present in the natural populations of Aedes albopictus could be implied in the transmission cycle and the viral pathogenesis of the CHIKV as it is already shown for other virus-arthropods-Wolbachia systems
Fernandes, Alana Batista, i 92-98197-7160. "Clonagem e expressão da proteína do capsídeo do vírus Chikungunya para produção de antígeno recombinante: Produção de antígeno recombinante através de gene sintético do vírus Chikungunya". Universidade Federal do Amazonas, 2016. http://tede.ufam.edu.br/handle/tede/5951.
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CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico
The Chikungunya virus (CHIKV) is an RNA virus (family Togaviridae, genus Alphavirus) transmitted to humans through the bite of female mosquitoes Aedes aegypti and Aedes albopictus. The clinical onset in CHIKV infection is most often characterized by fever and joint pain, and so far there is no specific antiviral therapy or vaccine for the treatment of the infection. The diagnosis of CHIKV infection is based on clinical and laboratory findings, with the latter being performed by virus isolation, reverse transcription-polymerase chain reaction (RT-PCR), serology, and rapid tests: To produce a recombinant antigen through the cloning and expression of the capsid protein (C) of CHIKV in order to detect anti-CHIKV antibodies in human serum samples by immunoenzymatic assay. A synthetic gene (gBlock), specifically designed for this study, corresponding to the protein C (400 base pair) of Chikungunya virus, was amplified by polymerase chain reaction (PCR) and then cloned into pGEM-T Easy system-Escherichia coli. The transformant clones were sequenced, and recombinant products were digested using the restriction endonucleases EcoRI and BamHI, and then subcloned and expressed in the vector pET-23a+ Escherichia coli BL21 (DE3). The recombinant protein C expression and the molecular weight were determined by SDS-PAGE and Dot Blot and purified by affinity chromatography using nickel column. A immunoenzymatic assay was performed using the recombinant antigen to detect IgM and IgG antibodies in sera from patients with CHIKV infection confirmed by the National Reference Laboratory of the Ministry of Health, as well as sera from patients tested positive for Mayaro virus, Dengue virus and Cytomegalovirus infection. The derived recombinant protein showed size and antigenicity compatible with the native protein C from the CHIKV; a concentration of 0.342 ng/mL of recombinant protein C was obtained using the pET-23a+ E. coli BL21 (DE3); the affinity chromatography using nickel column was effective to obtain the soluble protein C, confirmed by the Bradford method; the immunoenzymatic assay using the recombinant antigen showed cross-reactivity to others Alphavirus pathogens. The results indicate that the expression system pET-23a+ E. coli BL21 (DE3) was effective to produce the recombinant protein C of CHIKV, however the antigen was not sensitive enough to detect only the CHIKV infection.
O vírus Chikungunya (CHIKV) é um vírus de RNA (família Togaviridae, gênero Alphavirus), transmitido aos seres humanos através da picada de mosquitos fêmeas de Aedes aegypti e Aedes albopictus. O início das manifestações clínicas da infecção por CHIKV na maioria das vezes é caracterizada por febre e dor nas articulações, e até agora não existe uma terapia antiviral específico ou vacina para o tratamento da infecção. O diagnóstico da infecção CHIKV é baseado em achados clínicos e laboratoriais, com o último sendo realizada por isolamento do vírus, transcrição reversa-polimerase reação em cadeia (RT-PCR), sorologia e testes rápidos. Para produzir um antígeno recombinante através da clonagem e expressão da proteína do capsídeo (C) de CHIKV de modo a detectar anticorpos anti-CHIKV em amostras de soro humano, por ensaio imunoenzimático. Um gene sintético (gBlock), especificamente concebidos para esse estudo, correspondente à proteína C do capsídeo (400 pares de bases) do vírus Chikungunya, foi amplificado por reação em cadeia da polimerase (PCR) e, em seguida, clonado em pGEM-T Easy sistema de Escherichia coli. Os clones transformantes foram sequenciados, e os produtos recombinantes foram digeridos com as endonucleases de restrição EcoRI e BamHI, e depois subclonado e expresso no vector pET-23a+ e Escherichia coli BL21 (DE3). A expressão da proteína C recombinante e o peso molecular foram determinados por SDS-PAGE e Dot Blot e purificado por cromatografia de afinidade utilizando uma coluna de níquel. Um ensaio imunoenzimático foi realizada utilizando o antígeno recombinante para detecção de anticorpos IgM e IgG em soros de pacientes com infecção CHIKV confirmados pelo laboratório nacional de referência do Ministério da Saúde, bem como soros de pacientes positivos para o vírus Mayaro, vírus da dengue e citomegalovírus infecção. O derivado da proteína recombinante mostrou tamanho e antigenicidade compatível com a proteína C nativa do CHIKV; uma concentração de 0,342 ng / mL de proteína C recombinante foi obtido utilizando o pET-23a+ de E. coli BL21 (DE3); a cromatografia de afinidade utilizando uma coluna de níquel foi eficaz para obter a proteína C solúvel, confirmada pelo método de Bradford; o ensaio imunoenzimático utilizando o antígeno recombinante mostrou reatividade cruzada com outros agentes patogénicos de Aphavírus. Os resultados indicam que o sistema de expressão pET-23a+ de E. coli BL21 (DE3) foi eficaz para produzir a proteína C recombinante de CHIKV, no entanto, o antígeno não foi suficientemente sensível para detectar apenas a infecção CHIKV.
Alva-Urcia, Carlos, Miguel Angel Aguilar-Luis, Carlos Palomares-Reyes, Wilmer Silva-Caso, Luis Suarez-Ognio, Pablo Weilg, Carlos Manrique, Fernando Vasquez-Achaya, Valle Luis J. del i Valle-Mendoza Juana del. "Emerging and reemerging arboviruses: A new threat in Eastern Peru". Public Library of Science (PLoS), 2017. http://hdl.handle.net/10757/622421.
Pełny tekst źródłaRozen-Gagnon, Kathryn. "Chikungunya virus nonstructural proteins regulate replication fidelity and pathogenicity in vivo". Paris 7, 2014. http://www.theses.fr/2014PA077199.
Pełny tekst źródłaArboviruses cycle through both vertebrates and invertebrates, which requires them to adapt to disparate hosts while maintaining genetic integrity during genome replication. To study the genetic mechanisms and determinants of these processes, we use chikungunya virus (CHIKV), a re-emerging human pathogen transmitted by the Aedes mosquito. We isolated novel mutators with decreased replication fidelity and higher mutation frequencies, allowing us to examine the fitness of error-prone arbovirus variants. Although CHIKV mutators displayed no major replication defects in mammalian cell culture, they were attenuated in vivo. Unexpectedly, mutator phenotypes were suppressed in mosquito cells and the variants exhibited significant defects in RNA synthesis. Consequently, these replication defects resulted in strong selection for reversion during inection of mosquitoes. Since residue 483 is conserved among alphaviruses, we examined the analogous mutations in Sindbis virus (SINV), which also reduced polymerase fidelity and generated replication defects in mosquito cells. However, replication defects were mosquito cell-specific and were not observed in Drosophila S2 cells, allowing us to evaluate the potential attenuation of mutators in insect models where pressure for reversion was absent. Indeed, the SINV mutator variant was attenuated in fruit flies. These findings confirm that residue 483 is a determinant regulating alphavirus polymerase fidelity and demonstrate proof of principle that arboviruses can be attenuated in mammalian and insect hosts by reducing fidelity
Andersson, Klara. "Characterization of nsP-specific nanobodies targeting Chikungunya and Semliki Forest Virus". Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414971.
Pełny tekst źródłaKrystosik, Amy Robyn. "CHIKUNGUNYA, DENGUE, AND ZIKA IN CALI, COLOMBIA: EPIDEMIOLOGICAL AND GEOSPATIAL ANALYSES". Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1481111225042036.
Pełny tekst źródłaPatramool, Sirilaksana. "Interactions virus (dengue)-vecteurs (aedes) et mise en évidence d'une méthode d'isolement des virus de la dengue et du chikungunya". Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20139.
Pełny tekst źródłaDengue (DENV) and Chikungunya (CHIKV) viruses are two emerging arboviruses that are transmitted to humans by the bite of Aedes sp. mosquito vectors. Neither vaccines, nor medical treatments, are commercially available for these infections. It is, therefore, necessary to elaborate novel strategies to isolate the circulating viruses and block their transmission.Our understanding of the molecular mechanisms involved, during the infection of the Aedes vector by dengue virus (DENV), especially serotypes 1 and 3, remains very scant. We, therefore, performed a proteomics analysis of an Aedes albopictus cell line, infected by these two DENV serotypes, and showed that the cells use both anti-oxidant and energy-production mechanisms in the fight against the virus. These results should help to improve our knowledge of the interaction of the DENV virus and the Aedes mosquito vector, at the cellular level, with the aim of designing efficient strategies for the control of this virus. We have, in addition, developed a rapid and sensitive isolation technique, based on viral particle adsorption to magnetic beads coated with an anionic polymer. The use of this technique is of great interest, as it permits the rapid and simultaneous detection and isolation of CHIKV and DENV from samples with reduced viral loads
Zouache, Karima. "Interactions multipartites entre communautés symbiotiques, pathogènes et vecteurs : le système vectoriel bactéries, endosymbiotiques, virus chikungunya, moustiques aedes". Thesis, Lyon 1, 2010. http://www.theses.fr/2010LYO10183.
Pełny tekst źródłaAedes albopictus and Aedes aegypti transmit a large number of arboviruses, including dengue and chikungunya. In addition to viruses, mosquitoes harbour other symbionts that are able to affect its biology. For instance, the bacterium Wolbachia infects naturally Aedes albopictus. As for many insects, this bacterium is an obligate parasite that manipulates the host reproduction and can also interact with pathogens, modifying the transmission of the pathogens by the mosquitoes. Except Wolbachia, little is known about the bacteria associated with Aedes mosquitoes. First, we detected and localized bacteria in field-caught and laboratory populations of Aedes, using culture and non-culture methods including PCR, DGGE and in situ hybridization. The bacterial populations belonged to Alpha, Beta and Gammaproteobacteria as well as to Firmicutes. Then, the effects of chikungunya infection on Wolbachia and total bacterial community were measured using quantitative PCR and taxonomic microarrays. Results showed interactions between the different partners in this vectorial system
Pham, Thi Kim Lien. "Epidemiology and dynamic of dengue and chikungunya in several provinces in Vietnam". Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS095/document.
Pełny tekst źródłaDengue and chikungunya are both transmitted by Aedes aegypti and Aedes albopictus and can cause potentially severe and or debilitating chronic disease. They are the fastest spreading diseases, in part because of the climate change. Vietnam is a hyperendemicity country for dengue and is at risk to be like neighboring Cambodia affected both by dengue and chikungunya and be an overlapping area of distribution for both viruses. The aim of this PhD work was therefore to assess the status of single and dual infections all over the country, investigate the presence of chikungunya, assess the efficiency of the surveillance procedures routinely established and assess the diversity of mosquito populations and their potential respective role. A first part of the PhD dissertation is devoted to a bibliographic review. The second part comprises three chapters associated to three different publications. The first chapter is devoted to a surveillance study in the general hospital if the Southern Province of Dong Thap. A cohort of 131 patients with acute fever symptoms was investigated for the presence of dengue and chikungunya. 101 patients out of 131 were confirmed with dengue. All four dengue serotypes were detected with a predominance of DENV2 and DENV4. No chikungunya infection was detected although reported in neighboring Cambodia. A differential efficiency of serological dengue detection was observed. Efficiency was 29% upon admission and 53% after seven days on the same patients. There is thus a clear risk of dengue being underestimated while chikungunya is not systematically detected. Changes in detection and surveillance procedures are therefore proposed to increase the efficiency of dengue detection and continue the monitoring the emergence of CHIKV. The second Chapter is dedicated to the respective role of A. aegypti and A. albopictus in the 2011 outbreak in the Northern capital city of Hanoi. Only DENV-1 and DENV-2 serotypes were detected from the 140 patients hospitalized. A positive correlation was found between the population density of A. aegypti and the number of human cases and duration of outbreaks. This was not observed for A. albopictus. Three pools of A. aegypti were positive with dengue virus, two with DENV-1 and one with DENV-2. This work indicate clearly the role of A. aegypti in the 2011 Hanoi epidemics. The last chapter of the PhD is devoted to a crosscutting country wide survey in five provinces border with Lao PDR and Cambodia. In this work, a total of 558 serum samples were collected from patients admitted in the 2012-2014 period in five provincial preventive medicine centers with acute fever and symptoms compatible to DENV-CHIKV infection. All four dengue serotypes were found altogether but not in the same province. Only two serotypes were found at the maximum in a single province. No CHIKV was detected. A total of 1104 adult mosquitoes were collected inside and outside houses at the same place. Mosquito population density and vector indexes were assessed following capture of larvae. Differing densities of mosquito populations were found with the highest one being in the Long An province border with Cambodia. Dengue viruses were detected mostly in A. albopictus. CHIKV was also detected in A. albopictus mosquitoes. The phylogenetic analysis of the collected mosquitoes showed a large diversity of genotypes, all of them having been described in other parts of the world. This part of the PhD work underline the dual role of A. aegypti and A. albopictus, the increasing role of the latter and the high level of man-related very long distance mobility of mosquitoes. This work underlines the need of novel approaches for surveillance both at the clinical and at the entomological level to efficiently tackle the risk of dengue and chikungunya outbreaks
Uhrlaub, Jennifer L., Vesna Pulko, Victor R. DeFilippis, Rebecca Broeckel, Daniel N. Streblow, Gary D. Coleman, Byung S. Park i in. "Dysregulated TGF-β Production Underlies the Age-Related Vulnerability to Chikungunya Virus". PUBLIC LIBRARY SCIENCE, 2016. http://hdl.handle.net/10150/622415.
Pełny tekst źródłaGérardin, Patrick. "Impact en population de l'épidémie de Chikungunya à l'Ile de La Réunion". Paris 6, 2013. http://www.theses.fr/2013PA066042.
Pełny tekst źródłaChikungunya is an emerging infectious disease caused by an alphavirus (CHIKV) transmitted by Aedes mosquitoes (Ae albopictus, Ae aegypti). In years 2004-2007, several large scale outbreaks have hit the Indian Ocean area. Our objectives were to assess the burden of the epidemic in the Reunion island community (post-epidemic seroprevalence rate: 38. 2%, 300,000 persons infected) in terms of perceived morbidity, health-related quality of life (QoL), to identify the prognostic factors for musculoskeletal pain of chikungunya rheumatism (RMSP), and finally to determine the neurocognitive outcome of children infected at birth due to the vertical transmission of the virus. In the aim to measure the populational impact of the epidemic, we conducted two telephonic surveys using two random samples of the population of a seroprevalence survey. CHIKV was involved in a third of RMSP, 10% of light cerebral disorders, 7. 5% of sensorineural impairments, on average eighteen months after the end of the outbreak. The Qol was slightly altered in CHIKV-infected subjects. Predictors of chronic RMSP were age greater or equal than 45 years, severe initial rheumatic involvement at the acute phase of infection, and finally a strong humoral response against the CHIKV at plateau phase (high specific IgG titres). To measure the neurocognitive outcome of perinatal infection, we followed-up during two years a cohort of infected and uninfected children. More than half of infected children had a psychomotor delay, which correlated with the severity of the initial presentation. Our original findings open very interesting perspectives for the understanding of this new chronic infectious disease
Voss, James. "Chikungunya envelope glycoprotein structure at neutral PH determined by X-ray crystallography". Paris 7, 2011. http://www.theses.fr/2011PA077021.
Pełny tekst źródłaChikungunya is an emerging mosquito-bome alphavirus that has caused widespread outbreaks of debilitating human disease in the past five years. CHIKV invasion of susceptible cells is mediated by two viral glycoproteins, E1 and E2, which carry the main antigenic determinants and form an icosahedral shell at the virion surface. Glycoprotein E2, derived from furin cleavage of the p62 precursor to E3 and E2 is responsible for receptor binding and is the major viral antigen. The E1 protein is responsible for inducing the fusion of viral and cellular membranes in the target cell endosome which is required for release of the viral nucleocapsid into the cytoplasm to initiale infection of a cell. While the structure of E1 has been determined, the structure of E2"has remained elusive over the years. This thesis reports the atomic structures of the mature (E3/E2/E1) and immature (P62/E1) envelope glycoprotein complexes from Chikungunya virus determined by X-ray crystallography using a recombinant protein construct. This construct contained the covalently linked ectodomains of p62 and E1. Diffracting crystals of the purified complexes were obtained at neutral pH when the linker joining the ectodomains was cleaved. The glycoprotein structures were fit into reconstructions of the alphavirus virion obtained from cryo-electron microscopy (cryoEM). This analysis resulted in an inferred atomic model of the entire 25MDa surface of the highly conserved alphavirus virion and allowed for the synthesis of a wealth of genetic, biochemical, immunological and electron microscopy data accumulated over the years on alphaviruses in general
Wauquier, Nadia. "Exploration des réponses immunitaires induites par les virus Ebola, Chikungunya et Dengue". Paris 6, 2010. http://www.theses.fr/2010PA066548.
Pełny tekst źródłaReynolds, Erin Michelle. "Can a low-cost educational intervention result in a change in chikungunya knowledge and prevention practices? Developing and testing an intervention to prevent chikungunya in rural Tamil Nadu, India". Thesis, The University of Iowa, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3680068.
Pełny tekst źródłaCHIK is a viral infection transmitted by the Aedes aegypti mosquito which causes an illness with symptoms of severe joint pain, high fever, and rash. The joint pain can continue for months, causing disability and economic strain on families. This study included implementation of a baseline needs assessment, and development, implementation, and evaluation of an experimental community-based educational intervention in rural Tamil Nadu, India. A total of 184 households, across 12 purposively sampled villages (six intervention and six control), participated in the needs assessment between August and December 2010. The experimental community-based educational intervention was implemented between December 2010 and August 2011, in the six intervention villages. A total of 180 households, from the same 12 villages, participated in the post-intervention evaluation. A randomized block design with repetition was used to test whether there was a change in CHIK knowledge scores from baseline to post-intervention in the treatment group. A model including respondent variables, household larval status, household container larval status, recent experience with CHIK, numbers of livestock, socioeconomic position (SEP) variables, and water variables were used to predict CHIK knowledge scores in rural Tamil Nadu. Respondent age, measures of luxury amenities and water source were statistically significant predictors of knowledge in this model. The CHIK knowledge score increased from 9.0 to 9.4 in the intervention group (p=0.6457) and from 8.5 to 9.2 in the control group (p=0.393), showing that the educational intervention did not increase CHIK knowledge in the intervention group. Although this low-cost intervention, utilized in a resource poor area of Tamil Nadu, India did not result in an increase of CHIK knowledge, the process of developing the educational intervention may provide a template for future interventions. Future studies should investigate methods of sustainability in the use of educational messages.
Reynolds, Erin Michelle. "Can a low-cost educational intervention result in a change in Chikungunya knowledge and prevention practices? Developing and testing an intervention to prevent Chikungunya in rural Tamil Nadu, India". Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/1496.
Pełny tekst źródłaTantaléan, Yépez Derek, José Sánchez-Carbonel, Urizar Gabriela Ulloa, Luis Miguel Angel Aguilar, Morales Diego Espinoza, Wilmer Silva-Caso, Maria J. Pons i Valle Mendoza Juana Del. "Arboviruses emerging in Peru: need for early detection of febrile syndrome during El Niño episodes". Elsevier B.V, 2016. http://hdl.handle.net/10757/615645.
Pełny tekst źródłaRevisión por pares
Guerrero, Israel. "A Comparison of Chikungunya Virus Infection, Dissemination, and Cytokine Induction in Human and Murine Macrophages and Characterization of RAG2-/-γc-/- Mice as an Animal Model to Study Neurotropic Chikungunya Disease". BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8430.
Pełny tekst źródłaMoulay, Djamila. "Modélisation et analyse mathématique de systèmes dynamiques en épidémiologie.Application au cas du Chikungunya". Phd thesis, Université du Havre, 2011. http://tel.archives-ouvertes.fr/tel-00633827.
Pełny tekst źródłaFumagalli, Marcílio Jorge. "Desenvolvimento de métodos sorológicos para diagnóstico de infecções pelos vírus Chikungunya e Mayaro". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/17/17147/tde-15102018-115825/.
Pełny tekst źródłaDue the existence of 2 arthritogenic alphaviruses in Brasil, the viruses Mayaro (MAYV) and Chikungunya (CHIKV), it became important the development of efficient diagnose tests to discriminate their infections. In the present work, we developed indirect ELISAs for CHIKV and MAYV diagnosis using viral recombinant envelope proteins E2, produced in Escherichia coli, the rE2-CHIKV and rE2-MAYV. The recombinant E2 proteins had their antigenicity confirmed in the assay by using polyclonal antibodies produced in hyperimmunized mice with CHIKV, MAYV and other alphaviruses. The rE2-CHIKV ELISA detected homotypic murine antibodies and did not produced detectable cross-reactivity signal when using murine antibodies from other alphaviruses. The rE2-MAYV ELISA detected homotypic antibodies and also cross-reacted with murine anti-CHIKV antibodies, but not to other alphaviruses. These ELISAs were also tested for the detection of human antibodies, using patient sera suspected of arboviral infection. For rE2- CHIKV ELISA, it were tested 59 sera, resulting in 26 positive IgG samples. These ELISA results, when compared to those of a neutralizing assay, demonstrated a sensibility of 89.66% and specificity of 100%. The IgG positive human sera were detected in high dilutions by rE2-CHIKV ELISA. Regarding the detection of IgM, the rE2-CHIKV ELISA showed a moderate samples detection agreement when compared to other serologic assays. For rE2-MAYV ELISA, it were tested 68 sera, resulting in 23 positive IgG samples, of which 11 demonstrated to be positive by the neutralization assay, demonstrating a sensibility of 100% and specificity of 78.95%. Therefore, the rE2-CHIKV and rE2-MAYV ELISAs, especially for IgG detection, demonstrated to be properly sensitive and specific to be validated in studies using a greater number of samples, and also to be applied in the diagnosis of infected CHIKV and MAYV patients.
Moizeis, Raíza Nara Cunha. "Avaliação do perfil da resposta imune inata em pacientes infectados pelo vírus Chikungunya". PROGRAMA DE PÓS-GRADUAÇÃO EM CIÊNCIAS BIOLÓGICAS, 2018. https://repositorio.ufrn.br/jspui/handle/123456789/25525.
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A infecção pelo vírus Chikungunya causa alta morbidade devido principalmente a artralgia e artrite geradas. A inflamação induzida nas articulações pela infecção viral envolve a imunidade inata e adaptativa. Entretanto, os mecanismos imunológicos envolvidos na proteção ou patogênese não estão ainda, totalmente, elucidados. Dessa forma o objetivo do presente estudo foi avaliar as expressões de receptores da imunidade inata e citocinas induzidas por sua ativação em pacientes infectados pelo vírus Chikungunya. Neste estudo, foi avaliado a expressão de RNAm por PCR em tempo real dos receptores tipo Toll (TLR3, TLR7, TLR8, TLR9), RLR (MDA5 e RIG-1), Moléculas adaptadoras (TRIF e MyD88) e citocinas (IFNα, IFNβ, IFNγ, IL-6, IL-12 e TNFα) em sangue total de pacientes na fase aguda da infecção por Chikungunya (N=28) e em indivíduos saudáveis, não infectados (N=9) utilizados como grupo controle. Os pacientes infectados pelo CHIKV apresentaram aumento da expressão de RNAm de TLR3, em relação aos indivíduos saudáveis. Não foi observada diferença significativa da expressão de TLR7, TLR9, MDA5 e RIG-1 nos pacientes infectados pelo CHIKV, sendo observada, no entanto, uma redução da expressão de RNAm de TLR8, quando comparado aos indivíduos saudáveis. Nossos resultados indicam que a infecção pelo CHIKV em pacientes na fase aguda induz elevada produção de IFN-α, IFN-γ e IL-6, moléculas da imunidade inata, com ação antiviral provavelmente, devido ao reconhecimento do vírus por TLR3 e em menor proporção por MDA5 e RIG-1, além de mecanismos que, possivelmente, envolvam a colaboração de TLR9. Ainda, foram constatadas correlações positivas entre as expressões de RNAm de TLR3, TLR7, TLR9, MDA5 e RIG-1 com expressão IFN-α. De maneira interessante, também foram observadas correlações positivas entre as expressões de RNAm de TLR3 com IFN-α, IFN-γ e IL-12, e entre a expressão de RNAm de MDA5 com IFN-α, IFN-β, IFN-γ e IL-6, IL-12 e TNF-α.
Chikungunya virus infection cause high morbidity mainly due to arthalgia and arthritis generated. An inflammation induced in the joints by viral infection involve innate and adaptive immunity. However, the immunological mechanisms involved in protection or pathogenesis have not yet been completely elucidated. Thus the aim of the present study was to evaluate the expression of innate immunity receptors and cytokines induced by their activation in patients infected with the Chikungunya virus. In this study the expression of mRNA by real-time PCR of Toll receptors (TLR3, TLR7, TLR8, TLR9), RLR (MDA5 and RIG-1), adaptive molecules (TRIF and MyD88) and cytokines (IFN-α, IFN-β, IFN-γ, IL-6, IL-12 and TNF-α) in whole blood of patients in the acute phase of the Chikungunya infection (N=28). Uninfected cases (N=9) were used as negative controls. Pacients infected with CHIKV are older than TLR3 mRNA expression in relation to healthy languages. Influences of the expression of TLR7, TLR9, MDA5 and RIG-1 in CHIKV infected patients in the past have not been confirmed but have been shown to decrease TLR8 mRNA expression when they were found in the healthy populations. Factors related to CHIKV infection in pacients in the suck phase, infection with IFN-α, IFN-γ and IL-6, infections of innate immunity with antiviral action, recognition of the virus by TLR3 and to a lesser extent by MDA5 and RIG-1, in addition to mechanisms that possibly involve TLR9 collaboration. Furthermore, positive correlations were found between the mRNA expression of TLR3, TLR7, TLR9, MDA5 and RIG-1 with IFN-α expression. Interestingly, positive correlations between TLR3 mRNA expression with IFN-α, IFN-γ and IL-12 were also observed, and between MDA5 mRNA expression with IFN-α, IFN-γ and IL-12 were also observed, and between MDA5 mRNA expression with IFN-α, IFN-β, IFN-γ and IL-6, IL-12 and TNF-α.
Bourjot, Mélanie. "Recherche d'inhibiteurs de la réplication du virus Chikungunya issus de la biodiversité tropicale". Paris, Muséum national d'histoire naturelle, 2012. http://www.theses.fr/2012MNHN0015.
Pełny tekst źródłaIn order to discover inhibitors of viral replication of chikungunya (CHIKV), a screening was performed on 685 malagasy plants. Two species were selected: Flacourtia ramontchi (Salicaceae) and Anacolosa pervilleana (Olacaceae). The bioguided fractionation of the first species led to the isolation of eleven molecules of which ten were phenolic glycosides and six were new, while the study of Anacolosa pervilleana led to the characterization of seven molecules amongst which four polyacetylenic acids, two terpenoids and one cyanogenic glycoside. Unfortunately, these molecules have not shown any activity on CHIKV replication. Since a potent anti-CHIKV activity of a daphnane diterpenoid orthoester (DDO) isolated from a Trigonostemon species was discovered by serendipity, we have engaged chemical investigations of two species of Trigonostemon (Euphorbiaceae) : T. Cherrieri and T. Howii. The study of the EtOAc extract obtained from T. Cherrieri leaves led to the isolation of eight DDOs amongst which two were new. These molecules showed potent and selective antiviral activity on CHIKV replication. The study of the EtOAc bark extract of T. Howii allowed isolating seven compounds amongst which one new tigliane, four coumarins and two phenylpropanoids. The tigliane-type compound showed a moderate activity on CHIKV. This result led us to biologically investigate other tigliane diterpenoids amongst which phorbol 12-myristate 13-acetate had shown the most powerful anti-CHIKV activity ever found to date
Lacroix, Renaud. "Etude de terrain d'Aedes albopictus vecteur du Chikungunya sur l'Ile de la Réunion". Versailles-St Quentin en Yvelines, 2009. http://www.theses.fr/2009VERS0053.
Pełny tekst źródłaThe recent epidemics of Chikungunya confirmed the potential of Ae. Albopictus as a vector. For implementation of Sterile Insect Technique (SIT), Mark-Release-Recapture (MLR) experiments were conducted in La Réunion Island. A mouse baited BG-Sentinel trap shown to be efficient at trapping both males and females. Results indicates that Ae. Albopictus has a limited dispersal range, higher activity during wet season, similar survival for both sexes but higher during wet season, mates before bloodmeal during dry season and preferred heavily shaded vegetated areas. We conclude that SIT should settle close release points, a low frequency of releases, adapt to season number released and places of releases. There is still a lot of work to be done before application of SIT, experiments with sterile males will be necessary for optimisation of vector population control
Arias, Goeta Camilo. "Evolution et adaptation du virus chikungunya vis-à-vis des ses hôtes vecteurs". Paris 6, 2012. http://www.theses.fr/2012PA066691.
Pełny tekst źródłaArboviruses are characterized by high rates of mutation. However, it has been assumed that their evolution is constrained by requirement for alternate replication in vertebrate and invertebrate hosts. Host change would favor the emergence of new viral variants pre-existing in the viral population. Indeed, during the 2004 outbreak of chikungunya virus (CHIKV) in the Indian Ocean, a newly emerged epidemic variant harboring a single amino-acid substitution in the E1 glycoprotein was highly transmitted by an unusual mosquito vector, Aedes albopictus. We showed that when the original and the newly emerged epidemic variants were provided at equal titers in blood-meals, the epidemic variant was preferentially transmitted by Ae. Albopictus. Interestingly, when inoculating both variants into mosquitoes bypassing the midgut barrier, the epidemic variant was no longer selected in Ae. Albopictus. Our findings suggest that the midgut barrier plays a key role in the selection of the epidemic variant. Subsequent adaptive mutations in the CHIKV genome are likely to emerge questioning on the evolution of CHIKV. We evaluated if host alternation can limit CHIKV evolution and results in fitness trade-offs. To test this hypothesis, the newly emerging variant of CHIKV was serially or alternately passaged in mammalian or mosquito cells. After 30 passages, obtained CHIKV strains were genetically and phenotypically characterized. Our results were not in line with the general assumption stating that host alternation constrains CHIKV evolution. However, our experimental approach suggested that new amino-acid substitutions in the E2 glycoprotein could modulate the vector competence in mosquitoes
Schilte, Clémentine. "Rôle de l’interféron de type I dans la physiopathologie du virus du Chikungunya". Paris 6, 2010. http://www.theses.fr/2010PA066090.
Pełny tekst źródłaGodaert-Simon, Lidvine. "Aspects épidémiologiques et cliniques d'une infection par le virus du Chikungunya chez les sujets âgés de 65 ans et plus. : Etude sur les spécificités d'une atteinte par arbovirose dans une population âgée". Thesis, Antilles, 2017. http://www.theses.fr/2017ANTI0253/document.
Pełny tekst źródłaChikungunya virus infection is an emergent arthropod-borne alpha-virus transmitted by mosquito bites, and causes fever with debilitating arthritic illness. Chikungunya virus infection is still considered as an emerging public health problem in both tropical and temperate regions. The presence of favourable conditions in temperate regions has enabled propagation of the vector, leading to the emergence of the first autochthonous cases of CHIKV in Europe and the USA. Older people may be particularly concerned about infection during an outbreak. CVhikungunya virus infection prevalence rates are not fully known, and vary from 18% to 48% The use of predictive scores would thus be very helpful in this situation. We have showed that predictive scores developed in young population have poor diagnostic performances in elderly population. In fact, the populations described in observational studies of chikungunya virus infection were predominantly young subjects. Clinical and epidemiological data in older subjects (aged 65 and over) are sparse. The mortality and morbidity related to infection in elderly people is poorly documented. We showed that the usual clinical expression of CHIKV infection is different in elderly subjects (absence of fever, arthralgia or both). We have developed and validated a new Chikungunya virus infection screening score specifically for use in the aged population.Some questions remain, in particular concerning mid- or long-term consequences of infection in elderly people. In a preliminary study, we have showed that the mid-term mortality rate of aged people infected by Chikungunya was lower than that of uninfected aged people.We need to continue our work on this thematic to explore more precisely the consequences of chikungunya virus infection in elderly people (mid- and long-term mortality, loss of autonomy, chronic form…)
Boussier, Jeremy. "Chikungunya Virus Superinfection Exclusion and Defective Viral Genomes : Insights into Alphavirus Regulation of Genetic Diversity". Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCC181/document.
Pełny tekst źródłaArboviruses such as chikungunya virus (CHIKV) are responsible for millions of yearly infections, with no approved vaccines and limited treatments. Because they circulate between mosquitoes and humans, their fast adaptation potential to different hosts is key to pathogenesis. To achieve genome diversification, they rely on the error-prone nature of their self-encoded RNA-dependent RNA polymerase, which quickly generates a cloud of mutants, termed quasispecies. Quasispecies contain not only mutated genomes, but also shuffled genomes of different parental origin (through a process known as recombination), as well as genomes with large deletions, unable to replicate without the co-infection with a full-length helper genome, and thus termed defective viral genomes (DVGs). A tight regulation of the mutant cloud size is key to pathogenesis: if too small, it will limit the adaptation potential of the virus, whilst too big a quasispecies may lead to the fast accumulation of deleterious mutations. While regulation of the mutational landscape is achieved through the finely tuned error rate of the viral polymerase, recombination and DVG replication are influenced by the co-infection potential of the target cells.In this context, superinfection exclusion (SIE), a process by which infection by a first virus prevents infection by a second, closely related virus, can regulate quasispecies dynamics. While described in most viral families, mechanisms underlying SIE remain poorly characterised. Here, I show that CHIKV infection excludes subsequent infection by CHIKV, Sindbis virus and influenza A virus, but not West Nile virus. I demonstrate that CHIKV exclusion occurs at two steps, impacting independently viral penetration and replication, but does not directly influence binding, nor viral protein translation. I further show that SIE is interferon independent, and does not rely on host cell transcription nor on soluble cellular factors. Moreover, exclusion is not mediated by the action of a single CHIKV protein, suggesting that a cellular response may be at play. Assessing how different immunological pressures can shape quasispecies landscape may prove useful to a more thorough understanding of the interplay between viral evolution and the immune response. Although the unbiased study of point mutations has received much attention, less is known about the characteristics of DVGs, especially in alphaviruses. In the second part of this work, I develop bioinformatics tools to quickly isolate DVGs from next-generation sequencing data, and assess the advantages and drawbacks of pre-amplification steps to detect and quantify DVGs. Using these tools, I provide the first unbiased description of the DVG landscape generated through serial passaging of CHIKV in cell culture. In particular, I show that the DVG landscape is highly dependent on the cell type, with sequence patterns and open reading frames differing between DVGs generated in mammalian and insect cells. These results highlight the role of the cellular environment in shaping quasispecies, and DVGs in particular. Future work will help uncover the mechanisms underlying this crosstalk and may prove useful for the design of treatments targeting quasispecies dynamics
Raquin, Vincent. "Immunité innée et multi-infections chez le moustique (Diptera, Culicidae) : étude fonctionnelle des interactions Wolbachia-arbovirus-Aedes albopictus". Thesis, Lyon 1, 2012. http://www.theses.fr/2012LYO10341.
Pełny tekst źródłaArthropod-borne virus (arbovirus) are important cause of human diseases worldwide, leading to nearly 30.000 deaths every year. Many arboviruses like dengue virus (DENV), chikungunya virus (CHIKV) or Rift valley Fever virus (RVFV) are transmitted by mosquitoes, and global changes like climate warming or international trade increase vectors geographic range, thus facilitating the emergence of arbovirosis. Very few vaccines are currently available, and the use of insecticides remains the only way to prevent arbovirosis but cause adverse effects on ecosystems, and lead to resistance phenotypes in vector populations. Recent work showed that mosquito bacterial flora, especially bacteria from the genus Wolbachia, can modulate viral infection, a phenotype called microbial interference. These results provide a promising tool to limit transmission of arboviruses, but little is known about mosquito-Wolbachia-arbovirus interaction especially at the cellular level. We characterized for the first time this multipartite interaction in Aedes albopictus, an important mosquito vector of DENV and CHIKV, which is naturally infected by Wolbachia. Results showed an antiviral phenotype in Wolbachia-infected mosquitoes, compared to aposymbiotic insects. We used RNAseq to decipher the major mosquito pathways implemented during mono-infection by virus, bacteria or during bi-infection. Moreover, we developed an Ae. albopictus cell line stably infected by Wolbachia to go further in mechanical aspects, and showed that autophagy is a major pathway involved in Wolbachia-arbovirus interaction in Ae. albopictus
Sánchez-Carbonel, José, Derek Tantaléan-Yépez, Miguel Angel Aguilar-Luis, Wilmer Silva-Caso, Pablo Weilg, Fernando Vásquez-Achaya, Luis Costa, Johanna Martins-Luna, Isabel Sandoval i Valle-Mendoza Juana del. "Identification of infection by Chikungunya, Zika, and Dengue in an area of the Peruvian coast. Molecular diagnosis and clinical characteristics". BioMed Central Ltd, 2018. http://hdl.handle.net/10757/623066.
Pełny tekst źródłaPinto, Jose Reginaldo. "Investigação epidemiológica da infecção pelo vírus chikungunya e sua relção com a doença renal crônica e outras cormobidades". Universidade de Fortaleza, 2018. http://dspace.unifor.br/handle/tede/108414.
Pełny tekst źródłaThe northeastern region of Brazil has faced the largest outbreak of the Chikungunya virus (CHIKV) in its history in the last two years. There are still few studies on kidney involvement in CHIKV infection. The present study analyzes the clinical and epidemiological characteristics of CHIKV in the State of Ceará, Brazil, outlining the profile of the reported cases, investigating the risk factors for death. This is a cross-sectional study including all registered cases of CHIKV in the State of Ceará in 2016-2017, based on the official data of the Health Secretariat of the State of Ceará (SESA-CE). There were 182,731 cases in 2016 and 2017, with a mean age of 32.4 ± 14.6 years and a predominance of females (62%). The clinical picture was characterized by fever (88.6%), headache (72.9%), severe arthralgia (69.5%) and myalgia (65.6%). Among comorbidities, there was a predominance of systemic arterial hypertension (6.9%) and diabetes mellitus (2.9%). CKD was reported in 691 cases (0.3%). Only 3.3% of patients needed hospitalization and only 0.1% died due to infection. The majority of the patients who died were the elderly, the male and the less educated. Independent risk factors for death were: advanced age (OR 7.35, p<0.0001), male gender (OR 2.05, p<0.0001), leukopenia (OR 3.18, p<0.0001), vomiting (OR 2.19, p<0.0001), and comorbidities like hypertension (OR 3.74, p<0.0001), diabetes (OR 3.29, p<0.0001), and chronic kidney disease (OR 3.14, p<0.0001). They also had a significantly higher frequency of diabetes mellitus, hematological disorders, Liver diseases, hypertension, peptic ulcer diseases and autoimmune diseases. Mortality was significantly higher among CKD patients comparing with patients without CKD (3.0% vs. 0.2%, p<0.0001). CHIKV infection may manifest as a serious disease, especially during epidemic periods. Advanced age and low schooling were associated with a higher mortality risk. Leukopenia and vomiting were signs of severity that should be valued by the health team, as well as the presence of comorbidities, especially hypertension, diabetes and kidney disease.
A região nordeste do Brasil tem enfrentado nos últimos dois anos o maior surto de infecção pelo vírus Chikungunya (CHIKV) em sua história. Ainda existem poucos estudos sobre o envolvimento renal na infecção pelo CHIKV. O presente estudo analisa as características clínicas e epidemiológicas do CHIKV no Estado do Ceará, Brasil, delineando o perfil dos casos notificados, investigando os fatores de risco para óbito. Trata-se de um estudo transversal incluindo todos os casos registrados do CHIKV no Estado do Ceará em 2016-2017, com base nos dados oficiais da Secretaria da Saúde do Estado do Ceará (SESA-CE). Foram registrados 182.731 casos em 2016 e 2017, com média de idade de 32,4 ± 14,6 anos e predomínio do sexo feminino (62%). O quadro clínico foi caracterizado por febre (88,6%), cefaleia (72,9%), artralgia grave (69,5%) e mialgia (65,6%). Entre as comorbidades, houve predomínio de hipertensão arterial sistêmica (6,9%) e diabetes mellitus (2,9%). A DRC foi relatada em 691 casos (0,3%). Apenas 3,3% dos pacientes necessitaram de internação e apenas 0,1% foram a óbito devido à infecção. O grupo de pacientes que foi a óbito era em sua maioria composto por idosos, do sexo masculino e com menor escolaridade. Os fatores de risco independentes para óbito foram: idade avançada (OR: 7,35, p<0,0001), sexo masculino (OR 2,05, p<0,0001), leucopenia (OR: 3,18, p<0,0001), vômitos (OR: 2,19, p<0,0001) e comorbidades como hipertensão (OR: 3,74, p<0,0001), diabetes (OR: 3,29, p<0,0001) e doença renal crônica (OR: 3,14, p<0,0001). Eles também tiveram uma frequência significativamente maior de diabetes, distúrbios hematológicos, hepatopatias, hipertensão, úlcera péptica e doenças auto-imunes. A mortalidade foi significativamente maior entre pacientes com DRC em comparação com pacientes sem DRC (3,0% vs. 0,2%, p <0,0001). A infecção pelo CHIKV pode se manifestar como doença grave, especialmente durante períodos epidêmicos. Idade avançada e baixa escolaridade foram associados a maior risco de mortalidade. Leucopenia e vômitos foram sinais de gravidade que devem ser valorizados pela equipe de saúde, assim como a presença de comorbidades, especialmente hipertensão, diabetes e doença renal.
Del, Valle-Mendoza Juana, Fernando Vasquez-Achaya, Miguel Angel Aguilar-luis, Johanna Martins-Luna, Jorge Bazán-Mayra, Victor Zavaleta-Gavidia, Wilmer Silva-Caso i in. "Unidentified dengue serotypes in DENV positive samples and detection of other pathogens responsible for an acute febrile illness outbreak 2016 in Cajamarca, Peru". BioMed Central Ltd, 2020. http://hdl.handle.net/10757/655508.
Pełny tekst źródłaRevisión por pares