Your browser doesn't support javascript.

Portal Regional da BVS

Informação e Conhecimento para a Saúde

Home > Pesquisa > (mh:dengue or ti:dengue or tw:"Febre Hemorragica da Dengue" or tw:"Dengue Hemorrhagic Feve... (19.071)
Detalhe da pesquisa
Imprimir Exportar

Formato de exportação:



Adicionar mais destinatários

Enviar resultado
Resultados 1 - 20 de 19.071

Análisis de materiales didácticos e informativos sobre dengue en Argentina / Analysis of didactic and informative materials about dengue in Argentina / Análise de materiais didáticos e informativos sobre dengue na Argentina

Interface comun. saúde educ; 21(60): 35-49, Jan.-Mar. 2017. tab, graf
Artigo em Espanhol | LILACS-Express | ID: BIBLIO-829011


Presentamos un análisis de materiales didácticos e informativos sobre dengue, elaborados por Ministerios de Salud y Educación de diferentes jurisdicciones de Argentina. Realizamos un análisis de contenido indagando dimensiones de la salud, modelos didácticos, modelos epidemiológicos y concepciones acerca de participación. Inferimos que la perspectiva dominante tuvo una fuerte impronta biomédica, desde un modelo epidemiológico lineal multicausal. El eje principal fue el “manejo de criaderos”, acciones para reducir los recipientes domésticos con agua en los que se cría el mosquito Aedes aegypti. Si bien la participación de la comunidad apareció como central, la concepción subyacente fue de pseudoparticipación (la comunidad como ejecutora de recomendaciones, sin injerencia en las decisiones). Finalmente, si bien en las fundamentaciones de las propuestas didácticas inferimos una intencionalidad constructivista, en la mayoría de las actividades identificamos un modelo de transmisión-recepción.
We present an analysis of didactic and informative materials about dengue elaborated by Health and Education Ministries of Argentina. We performed Content Analysis inquiring aspects regarding health dimensions, didactic models, epidemiological models and participation concepts. We inferred that the dominant perspective had a strong biomedical imprint within a linear multicausal model. The main focus was “breeding site reduction”, actions to diminish domestic water-holding containers where Aedes aegypti breeds. Regardless of the importance given to participation, the underlying concept was pseudo participation (the community as mere target for recommendations, without influence in decisions). Finally, despite finding constructivist intentions in the introductions of didactical materials, we identified a transmission-reception model in most activities.
Apresentamos uma análise de materiais didáticos e informativos sobre dengue produzidos pelos Ministérios da Saúde e da Educação da Argentina. Realizamos uma Análise de Conteúdo indagando sobre dimensões da saúde, modelos didáticos, modelos epidemiológicos e conceitos de participação. Nós inferimos que a perspectiva dominante foi biomédica a partir de um modelo linear multi-causal. O foco principal foi ações de “redução de criadouros” para diminuir recipientes com água para uso doméstico, onde o Aedes aegypti cria-se. Não obstante a centralidade da participação, o conceito subjacente foi pseudoparticipação (a comunidade como destinatária de recomendações, sem influência nas decisões). Finalmente, apesar de identificar intenções construtivistas nas introduções dos materiais didáticos, caracterizamos um modelo de transmissão–recepção nas atividades.
Biblioteca responsável: BR1.1

DDX50 inhibits the replication of dengue virus 2 by upregulating IFN-ß production.

Arch Virol; 2017 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-28181036


Dengue virus (DENV) infects approximately 390 million people per year, and each of the four DENV serotypes (DENV-1, DENV-2, DENV-3, and DENV-4) is capable of causing infection. At present, there is no antiviral drug available for the treatment of DENV. Several DExD/H-box helicases have been shown to be involved in the antiviral immune response or viral replication. In the present study, we investigated the role of DDX50 in DENV-2 RNA replication. Our data showed that the level of DENV-2 RNA increased in DDX50 knockdown cells during an early stage of viral infection and decreased in DDX50-overexpressing cells. DDX50, in conjunction with RIG-I and MDA5, upregulated the production of IFN-ß in infected cells through an additive effect on the IFN-ß promoter. Furthermore, transcription of several IFN-stimulated genes was increased in DDX50-overexpressing cells infected with DENV-2. These results provide evidence that DDX50 negatively regulates DENV-2 replication during the early stages of infection by inducing IFN-ß production.

Zika Virus, Chikungunya Virus, and Dengue Virus in Cerebrospinal Fluid from Adults with Neurological Manifestations, Guayaquil, Ecuador.

Front Microbiol; 8: 42, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28174559


Zika virus (ZIKV), chikungunya virus (CHIKV), and dengue virus (DENV) have been associated with clinical presentations that involve acute neurological complaints. In the current study, we identified ZIKV, CHIKV, and DENV in cerebrospinal fluid (CSF) samples from patients admitted to the Hospital Luis Vernaza (Guayaquil, Ecuador) to the Emergency Room or the Intensive Care Unit, with neurological symptoms and/or concern for acute arboviral infections. Viral RNA from one or more virus was detected in 12/16 patients. Six patients were diagnosed with meningitis or encephalitis, three with Guillain-Barré Syndrome, and one with CNS vasculitis. Two additional patients had a systemic febrile illness including headache that prompted testing of CSF. Two patients, who were diagnosed with encephalitis and meningoencephalitis, died during their hospitalizations. These cases demonstrate the breadth and significance of neurological manifestations associated with ZIKV, CHIKV, and DENV infections.

The citrus flavanone naringenin impairs dengue virus replication in human cells.

Sci Rep; 7: 41864, 2017 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-28157234


Dengue is one of the most significant health problems in tropical and sub-tropical regions throughout the world. Nearly 390 million cases are reported each year. Although a vaccine was recently approved in certain countries, an anti-dengue virus drug is still needed. Fruits and vegetables may be sources of compounds with medicinal properties, such as flavonoids. This study demonstrates the anti-dengue virus activity of the citrus flavanone naringenin, a class of flavonoid. Naringenin prevented infection with four dengue virus serotypes in Huh7.5 cells. Additionally, experiments employing subgenomic RepDV-1 and RepDV-3 replicon systems confirmed the ability of naringenin to inhibit dengue virus replication. Antiviral activity was observed even when naringenin was used to treat Huh7.5 cells 24 h after dengue virus exposure. Finally, naringenin anti-dengue virus activity was demonstrated in primary human monocytes infected with dengue virus sertoype-4, supporting the potential use of naringenin to control dengue virus replication. In conclusion, naringenin is a suitable candidate molecule for the development of specific dengue virus treatments.

Identification of microRNAs expressed in the midgut of Aedes albopictus during dengue infection.

Parasit Vectors; 10(1): 63, 2017 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-28159012


BACKGROUND: The midgut is the first barrier to dengue virus (DENV) infections of mosquitoes and therefore is a major bottleneck for the subsequent development of vector competence. However, the molecular mechanisms responsible for this barrier are unknown. RESULTS: We constructed three small RNA libraries from the midguts of adult Aedes albopictus females that had been fed on either sugar solution, an uninfected blood meal, or a blood meal infected with DENV-2, and112 conserved microRNAs represented by 173 miRNA sequences were identified, with 34 novel microRNAs predicted by Mireap, RNAfold and Sfold software. In addition, the expression of aal-miR-1174, aal-miR-2951 and aal-miR-956 was confirmed via stem-loop quantitative real-time PCR (qRT-PCR). Compared with microRNA expression profiles of mosquitoes that had ingested a regular blood meal, 43 microRNAs were upregulated and 4were downregulated in mosquitoes that had ingested a DENV-2-infected blood meal. Among the differentially expressed microRNAs, miR-1767, miR-276-3p, miR-4448 and miR-4728-5p were verified via stem-loop qRT-PCR. CONCLUSIONS: Analyses indicated that the changing patterns in miRNA expression during DENV-2 infection were significant and varied at different time points post infection. Most miRNA were upregulated at 24 h but were downregulated at 48 h post DENV-2 intake. The aal-miR-4728-5p was chosen for an in vitro transient transfection assay, and the results show that this miRNA enhances DENV replication in C6/36 cells. This study provides the first information on microRNAs expressed in the midgut of Ae. albopictus and describes species-specific changes in their expression levels following infection by DENV-2.

Transcriptome analysis of Aedes aegypti in response to mono-infections and co-infections of dengue virus-2 and chikungunya virus.

Artigo em Inglês | MEDLINE | ID: mdl-28161634


Chikungunya virus (CHIKV) and Dengue virus (DENV) spread via the bite of infected Aedes mosquitoes. Both these viruses exist as co-infections in the host as well as the vector and are known to exploit their cellular machinery for their replication. While there are studies reporting the changes in Aedes transcriptome when infected with DENV and CHIKV individually, the effect both these viruses have on the mosquitoes when present as co-infections is not clearly understood. In the present study, we infected Aedes aegypti mosquitoes with DENV and CHIKV individually and as co-infection through nanoinjections. We performed high throughput RNA sequencing of the infected Aedes aegypti to understand the changes in the Aedes transcriptome during the early stages of infection, i.e., 24 h post infection and compared the transcriptome profiles during DENV and CHIKV mono-infections with that of co-infections. We identified 190 significantly regulated genes identified in CHIKV infected library, 37 genes from DENV library and 100 genes from co-infected library and they were classified into different pathways. Our study reveal that distinct pathways and transcripts are being regulated during the three types of infection states in Aedes aegypti mosquitoes.

A case report of intravenous posaconazole in hepatic and renal impairment patient with invasive Aspergillus terreus infection: safety and role of therapeutic drug monitoring.

BMC Pharmacol Toxicol; 18(1): 8, 2017 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-28143591


BACKGROUND: Invasive aspergillosis (IA) is a fatal infectious complication among immunocompromised patients. Aspergillus terreus, the fourth common species can be difficult to treat due to a unique resistance pattern. To date, there has been no report on safety and dose adjustment when intravenous posaconazole is selected in hepatic and renal impairment patient. We present a rare case of intravenous posaconazole use in a hepatic and renal impairment patient with invasive A. terreus pulmonary infection. To our knowledge, this is the first report of intravenous posaconazole use in IA due to A. terreus with hepatic and renal impairment focusing on drug safety and role of therapeutic drug monitoring (TDM). CASE PRESENTATION: A 37-year-old previously healthy man with diagnosis of dengue hemorrhagic fever and shock complicated with hepatic and renal impairment proposed to have proven invasive A. terreus pulmonary infection is described. Due to lack of good clinical response and concern of potential adverse effects whilst on intravenous voriconazole, intravenous posaconazole 300 mg every 48 h was chosen with confirmed therapeutic plasma concentrations. Despite the death of the patient and IA deemed uncontrollable, there were no significant side effects attributable to intravenous posaconazole use demonstrated over a period of 34 days. CONCLUSIONS: Intravenous posaconazole use with TDM implementation maybe a safe alternative option to standard therapy. Therapeutic plasma posaconazole level may be reached at lower dosing regimen in renal and hepatic impairment patient. However, explanations of clinical failure on this patient with immunodeficiency state were multifactorial.

Patterns of cellular immunity associated with experimental infection with rDEN2Δ30 (Tonga/74) supports its suitability as a human DENV challenge strain.

J Virol; 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28148797


A deletion variant of the DENV2 Tonga/74 strain lacking 30 nucleotides from its 3' untranslated region (rDEN2Δ30) has previously been established for use in a controlled DENV human challenge model. To evaluate if this model is appropriate to derive correlates of protection for DENV vaccines based on cellular immunity, we wanted to compare how the cellular immune response to this challenge strain compares to the response induced by natural infection. To achieve this, we predicted HLA class I and class II restricted peptides from rDEN2Δ30 and used them, in an IFN-gamma ELISPOT assay, to interrogate CD8 and CD4 T cell responses in healthy volunteers infected with rDEN2Δ30. At the level of CD8 responses, vigorous ex vivo responses were detected in approximately 80% of donors. These responses were similar in terms of magnitude and numbers of epitopes recognized to previously reported responses observed in PBMC from donors from DENV hyper-endemic regions. The similarity extended to the immunodominance hierarchy of the DENV nonstructural proteins NS3, NS5, and NS1 being dominant in both donor cohorts. At the CD4 level, responses were less vigorous compared to natural DENV infection, and were more focused on nonstructural proteins. The epitopes recognized following rDEN2Δ30 infection and natural infection were largely overlapping for both CD8 (100%) and CD4 (85%) responses. Finally, rDEN2Δ30 induced stronger CD8 responses compared to other more attenuated DENV isolates. IMPORTANCE: The lack of a known correlate of protection and the failure of a neutralizing antibody to correlate with protection against dengue have highlighted the need for human DENV challenge model to better evaluate the candidate live attenuated dengue vaccines. In this study we sought to characterize the immune profiling of rDEN2Δ30 infected subjects comparing them with subjects from areas where DENV is hyperendemic. Our data demonstrate that T cell responses to rDENV2Δ30 are largely similar to natural infection in terms of specificity, highlighting this virus as an appropriate human model for the T cell response to primary DENV2 infection.

Superinfection Interference between Dengue-2 and Dengue-4 Viruses in Aedes aegypti Mosquitoes.

Trop Med Int Health; 2017 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-28150899


OBJECTIVE: Dengue virus consists of four antigenically distinct serotypes (DENV 1-4) that are transmitted to humans by Aedes aegypti and Ae. albopictus mosquitoes. In many dengue-endemic regions, co-circulation of two or more DENV serotypes is fairly common increasing the likelihood for exposure of the two vectors to multiple serotypes. We used a model system of DENV-2 and DENV-4 to investigate how prior exposure of Aedes aegypti to one DENV serotype affects its susceptibility to another serotype. METHODS: Ae. aegypti mosquitoes were sequentially infected with DENV-2 and DENV-4 and the infection and dissemination rates for each virus determined. RESULTS: We found that prior infection of Ae. aegypti mosquitoes with DENV-4 rendered them significantly less susceptible to secondary infection with DENV-2. Although the results were not statistically significant, mosquitoes infected with DENV-2 were also less susceptible to secondary infection with DENV-4. The midgut dissemination and population dissemination rates for DENV-2 were significantly higher than those of DENV-4 when either virus was administered 7 days after administration of either a non-infectious blood meal or a blood meal containing a heterologous dengue serotype. CONCLUSION: These results demonstrate that superinfection interference between DENV serotypes is possible within Ae. aegypti mosquitoes but its effect on DENV epidemiology may be dependent on the fitness of interacting serotypes. This article is protected by copyright. All rights reserved.

Dengue virus serotype 2 infection alters midgut and carcass gene expression in the Asian tiger mosquito, Aedes albopictus.

PLoS One; 12(2): e0171345, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28152011


BACKGROUND: The Asian tiger mosquito, Aedes albopictus is currently an important vector for dengue, chikungunya and Zika virus, and its role in transmission of arthropod-borne viruses (arboviruses) may increase in the future due to its ability to colonize temperate regions. In contrast to Aedes aegypti, the dominant vector of dengue, chikungunya and Zika virus, genetic responses of Ae. albopictus upon infection with an arbovirus are not well characterized. Here we present a study of the changes in transcript expression in Ae. albopictus exposed to dengue virus serotype 2 via feeding on an artificial bloodmeal. METHODOLOGY/PRINCIPAL FINDINGS: We isolated midguts and midgut-free carcasses of Ae. albopictus fed on bloodmeals containing dengue virus as well as controls fed on virus-free control meals at day 1 and day 5 post-feeding. We confirmed infection of midguts from mosquitoes sampled on day 5 post-feeding via RT-PCR. RNAseq analysis revealed dynamic modulation of the expression of several putative immunity and dengue virus-responsive genes, some of whose expression was verified by qRT-PCR. For example, a serine protease gene was up-regulated in the midgut at 1 day post infection, which may potentially enhance mosquito susceptibility to dengue infection, while 14 leucine-rich repeat genes, previously shown to be involved in mosquito antiviral defenses, were down-regulated in the carcass at 5 days post infection. The number of significantly modulated genes decreased over time in midguts and increased in carcasses. CONCLUSION/SIGNIFICANCE: Dengue virus exposure results in the modulation of genes in a time- and site-specific manner. Previous literature on the interaction between mosquitoes and mosquito-borne pathogens suggests that most of the changes that occurred in Ae. albopictus exposed to DENV would favor virus infection. Many genes identified in this study warrant further characterization to understand their role in viral manipulation of and antiviral response of Ae. albopictus.

A heparin-functionalized carbon nanotube-based affinity biosensor for dengue virus.

Biosens Bioelectron; 91: 811-816, 2017 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-28152487


Dengue virus is an arthropod-borne virus transmitted primarily by Aedes mosquitos and is major cause of disease in tropical and subtropical regions. Colloquially known as Dengue Fever, infection can cause hemorrhagic disorders and death in humans and non-human primates. We report a novel electronic biosensor based on a single-walled carbon nanotube network chemiresistive transducer that is functionalized with heparin for low-cost, label-free, ultra-sensitive, and rapid detection of whole dengue virus (DENV). Heparin, an analog of the heparan sulfate proteoglycans that are receptors for dengue virus during infection of Vero cells and hepatocytes, was used for the first time in a biosensor as a biorecognition element instead of traditional antibody. Detection of DENV in viral culture supernatant has similar sensitivity as the corresponding viral titer in phosphate buffer despite the presence of growth media and Vero cell lysate. The biosensor demonstrated sensitivity within the clinically relevant range for humans and infected Aedes aegypti. It has potential application in clinical diagnosis and can improve point-of-care diagnostics of dengue infection.

How Did the Dengue Fever Outbreak Progress in Yoyogi Park, Tokyo, in 2014?-Evaluation Based on a Mathematical Model.

Nihon Eiseigaku Zasshi; 72(1): 55-65, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28154363


OBJECTIVES: In the summer of 2014, an outbreak of autochthonous dengue fever occurred in Yoyogi Park and its vicinity, Tokyo, Japan. In this study, we investigated how the dengue fever outbreak progressed in Yoyogi Park using a mathematical model. METHODS: This study was limited to the transmission of the dengue virus in Yoyogi Park and its vicinity. We estimated the distributions of the intrinsic incubation period and infection dates on the basis of epidemiological information on the dengue outbreak in 2014. We searched for an assumption that satisfactorily explains the outbreak in 2014 using rough estimates of secondary and tertiary infection cases. We constructed a mathematical model for the transmission of the dengue virus between humans and Aedes albopictus. RESULTS: We carried out 1,000-trial stochastic simulations for all combinations of three kinds of assumption about Ae. albopictus and asymptomatic infection with each of three levels. Simulation results showed that the scale of the outbreak was markedly affected by the daily survival rate of Ae. albopictus. The outbreak involved a small number of secondary infection cases, reached a peak at tertiary infection, and transformed to termination at the fourth infection. Under some assumptions, the daily progress of onset cases was within a range between the 1st-3rd quartiles of 1,000 trials for 87% of dates and within a range between the minimum and maximum for all dates. CONCLUSIONS: It is important to execute plans to detect asymptomatic cases and reduce the survival rate of Ae. albopictus to prevent the spread of tertiary infections unless an outbreak is suppressed at the secondary infection stage.

Hepatitis and thrombocytopenia: markers of dengue mortality.

Trop Doct; : 49475517691878, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28166687


Dengue fever is of great concern to public health in India as it contributes significantly to the burden of healthcare. The aim of our study was to measure mortality in dengue and its association with hepatitis and thrombocytopenia. Our study was performed in a tertiary care setting in the state of Kerala in southern India. Adult patients admitted in the year 2013 were included. Among 1308 confirmed dengue patients, the mortality rate was 1.76%. Hepatitis and thrombocytopenia were present in over 80% of all patients, but severe hepatitis was seen in 11.4% and severe thrombocytopenia in 9.3%. These were markers of fatal outcome. Other factors significantly associated with mortality were age >60 years, male sex, diabetes and the presence of any co-morbidity.

Imported Dengue Infection in a Spanish Hospital with a High Proportion of Travelers from Africa: A 9-Year Retrospective Study.

Am J Trop Med Hyg; 2017 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-28167601


Epidemiological data on dengue in Africa are still scarce. We investigated imported dengue infection among travelers with a high proportion of subjects from Africa over a 9-year period. From January 2005 to December 2013, blood samples from travelers with clinical suspicion of dengue were analyzed. Dengue was diagnosed using serological, antigen detection, and molecular methods. Subjects were classified according to birthplace (Europeans versus non-Europeans) and last country visited. Overall, 10,307 serum samples corresponding to 8,295 patients were studied; 62% were European travelers, most of them from Spain, and 35.9% were non-Europeans, the majority of whom were born in Africa (mainly Equatorial Guinea) and Latin America (mainly Bolivia, Ecuador, and Colombia). A total of 492 cases of dengue were identified, the highest number of cases corresponding to subjects who had traveled from Africa (N = 189), followed by Latin America (N = 174) and Asia (N = 113). The rate of cases for Africa (4.5%) was inferior to Asia (9%) and Latin America (6.1%). Three peaks of dengue were found (2007, 2010, and 2013) which correlated with African cases. A total of 2,157 of past dengue infections were diagnosed. Non-Europeans who had traveled from Africa had the highest rate of past infection (67.8%), compared with non-Europeans traveling from Latin America (38.7%) or Asia (35%). Dengue infection in certain regions of Africa is underreported and the burden of the disease may have a magnitude similar to endemic countries in Latin America. It is necessary to consider dengue in the differential diagnosis of other febrile diseases in Africa.

Clinical Profile of Dengue Infection in Immune-compromised Children.

Indian Pediatr; 2017 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-28159953


Review of records of children admitted with dengue infection was carried out to compare clinical and laboratory parameters, course of illness, and outcome between immune-compromised and immune competent patients. Statistically significant differences were found in days to platelet recovery (P=0.03), hepatic dysfunction (P= 0.04), and higher requirement of fluid (P= 0.01) in immunecompromised group.

Undifferentiated tropical febrile illness in Cordoba, Colombia: Not everything is dengue.

J Infect Public Health; 2017 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-28162961


In Colombia, undifferentiated tropical febrile illness (UTFI) are frequent and of considerable concern. They also share many clinical features. Between 2012 and 2013 in an endemic tropical area of Cordoba, Colombia, we conducted a prospective study to establish an etiological diagnosis of UTFI. Using diagnostic tests for dengue, leptospirosis, hantavirus, malaria, rickettsia, brucellosis, hepatitis A and B on 100 patients recruited for the study. We identified 69 patients with presumed UTFI: leptospirosis (n=27), dengue (n=26), hantavirus infection (n=4), malaria (n=4), rickettsial infection (n=2), hepatitis A (n=1), and brucellosis (n=1); no hepatitis B cases were detected. Co-infections with malaria and leptospirosis (n=1), hepatitis A and dengue (n=1), hantavirus and dengue (n=1), hantavirus, dengue, and leptospirosis (n=1) were also identified. No etiologic agent was identified for 31 patients. We conclude that other etiologic agents besides dengue virus deserve greater attention by physicians and public health authorities in tropical area of Colombia.
Resultados 1 - 20 de 19.071