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1.
Braz. j. infect. dis ; 25(2): 101542, 2021. tab
Article in English | LILACS | ID: biblio-1278571

ABSTRACT

ABSTRACT In response to the Zika epidemics in Brazil, the ZDC molecular assay (Bio-Manguinhos) was developed and registered at the Brazilian Regulatory Agency of Health Surveillance - ANVISA. The circulation of Zika (ZIKV) Dengue (DENV) and Chikungunya (CHIKV) viruses and their clinical similarities are challenges to correctly diagnose these viruses. The simultaneous detection of ZIKV, DENV and CHIKV is an important tool for diagnosis and surveillance. Here, we present the analytical and clinical performance evaluation of ZDC molecular assay (Bio-Manguinhos) at the public health laboratories three years after its registration at ANVISA. The clinical performance demonstrates the ZDC molecular assay (Bio-Manguinhos) has 100% sensitivity and 100% specificity to detect and discriminate ZIKV, CHIKV, and DENV from clinical plasma samples. The ZDC molecular assay (Bio-Manguinhos) results were highly reproducible and no cross-reactivity was seen during testing with a panel of other infectious agents. In conclusion, the ZDC molecular assay (Bio-Manguinhos) is an accurate and reliable tool to monitor Zika, dengue and chikungunya infections in countries like Brazil with simultaneous circulation of the three viruses.


Subject(s)
Humans , Zika Virus/genetics , Zika Virus Infection/diagnosis , Brazil , Chikungunya virus/genetics , Dengue/diagnosis , Dengue Virus/genetics , Chikungunya Fever/diagnosis , Laboratories
2.
Rev. bras. epidemiol ; 24: e210020, 2021. tab, graf
Article in English | LILACS | ID: biblio-1156025

ABSTRACT

Objective: To describe the entry of Dengue virus (DENV) serotypes in Brazil and its federative units. Methods: A systematic review of studies published between 1980 and 2018 in databases and in the gray literature was performed using descriptors related to the years of entry of the DENV serotypes. Additionally, experts and official sources of information (Brazilian Ministry of Health) were consulted. Results: From 100 publications selected for the systematic review, 26 addressed the entry of DENV serotypes in the North region of the country, 33 in the Northeast, 24 in the Southeast, 14 in the Central-West, and five in the South. DENV-1 and DENV-4 were introduced in the North region in 1981. DENV-2 was introduced in the Southeast in 1990. DENV-3 was introduced in the North in 1999. Conclusion: The rapid expansion of dengue throughout the Brazilian territory was verified from the second half of the 1980s, with the gradual entry of the four serotypes, which resulted in the emergence of epidemics of arbovirus, which are currently verified in the country. Considering the epidemiology of the disease, more information should be disseminated and published in the wide-ranging scientific literature for a better understanding of the spread and circulation of DENV serotypes.


RESUMO: Objetivo: Descreveu-se a entrada de sorotipos do vírus da Dengue (DENV) no Brasil e em suas unidades federativas. Métodos: Realizou-se uma revisão sistemática de estudos publicados entre 1980 e 2018 em bancos de dados e na literatura cinzenta, utilizando-se descritores relacionados aos anos de entrada dos sorotipos do DENV. Além disso, consultou-se especialistas e fontes oficiais de informação (Ministério da Saúde do Brasil). Resultados: Das 100 publicações selecionadas para a revisão sistemática, 26 abordaram a entrada de sorotipos de DENV na região Norte do país, 33 no Nordeste, 24 no Sudeste, 14 no Centro-Oeste e cinco no Sul. O DENV-1 e o DENV-4 foram introduzidos na região Norte em 1981. O DENV-2 foi introduzido no Sudeste em 1990. O DENV-3 foi introduzido no Norte em 1999. Conclusão: A rápida expansão da dengue por todo o território brasileiro foi verificada a partir da segunda metade dos anos de 1980, com a entrada gradativa dos quatro sorotipos, o que resultou no surgimento de epidemias da arbovirose, que são atualmente verificadas no país. Considerando a epidemiologia da doença, mais informações devem ser divulgadas e publicadas na literatura científica de amplo alcance, para melhor entendimento da propagação e circulação dos sorotipos de DENV.


Subject(s)
Humans , Dengue/epidemiology , Dengue Virus/genetics , Brazil/epidemiology , Serogroup , Geography
3.
Braz. j. infect. dis ; 24(1): 13-24, Feb. 2020. tab, graf
Article in English | LILACS | ID: biblio-1089334

ABSTRACT

ABSTRACT Dengue has been a significant public health problem in Colombia since the simultaneous circulation of the four dengue virus serotypes. The replicative fitness of dengue is a biological feature important for virus evolution and contributes to elucidating the behavior of virus populations and viral pathogenesis. However, it has not yet been studied in Colombian isolates. This study aimed to compare the replicative fitness of the four dengue virus serotypes and understand the association between the serotypes, their in vitro infection ability, and their replication in target cells. We used three isolates of each DENV serotype to infect Huh-7 cells at an MOI of 0.5. The percentage of infected cells was evaluated by flow cytometry, cell viability was evaluated by MTT assay, and the pathogenicity index was calculated as a ratio of both parameters. The replicative fitness was measured by the number of viral genome copies produced using quantitative PCR and the production of infectious viral progeny was measured by plaque assay. We showed that Huh-7 cells were susceptible to infection with all the different strain isolates. Nevertheless, the biological characteristics, such as infectious ability and cell viability, were strain-dependent. We also found different degrees of pathogenicity between strains of the four serotypes, representative of the heterogeneity displayed in the circulating population. When we analyzed the replicative fitness using the mean values obtained from RT-qPCR and plaque assay for the different strains, we found serotype-dependent behavior. The highest mean values of replicative fitness were obtained for DENV-1 (log 4.9 PFU/ml) and DENV-4 (log 5.28 PFU/ml), followed by DENV-2 (log 3.9 PFU/ml) and DENV-3 (log 4.31 PFU/ml). The internal heterogeneity of the replicative fitness within each serotype could explain the simultaneous circulation of the four DENV serotypes in Colombia.


Subject(s)
Humans , Virus Replication/genetics , Dengue Virus/genetics , Dengue Virus/pathogenicity , Serogroup , Viral Plaque Assay , Reference Values , Tetrazolium Salts , Time Factors , RNA, Viral/genetics , Cell Line , Cell Survival , Cells, Cultured , Colombia , Reverse Transcriptase Polymerase Chain Reaction , Flow Cytometry , Formazans , Liver/cytology
4.
Mem. Inst. Oswaldo Cruz ; 115: e190423, 2020. graf
Article in English | LILACS, SES-SP | ID: biblio-1135264

ABSTRACT

BACKGROUND Despite efforts to mitigate the impact of dengue virus (DENV) epidemics, the virus remains a public health problem in tropical and subtropical regions around the world. Most DENV cases in the Americas between January and July 2019 were reported in Brazil. São Paulo State in the southeast of Brazil has reported nearly half of all DENV infections in the country. OBJECTIVES To understand the origin and dynamics of the 2019 DENV outbreak. METHODS Here using portable nanopore sequencing we generated20 new DENV genome sequences from viremic patients with suspected dengue infection residing in two of the most-affected municipalities of São Paulo State, Araraquara and São José do Rio Preto. We conducted a comprehensive phylogenetic analysis with 1,630 global DENV strains to better understand the evolutionary history of the DENV lineages that currently circulate in the region. FINDINGS The new outbreak strains were classified as DENV2 genotype III (American/Asian genotype). Our analysis shows that the 2019 outbreak is the result of a novel DENV lineage that was recently introduced to Brazil from the Caribbean region. Dating phylogeographic analysis suggests that DENV2-III BR-4 was introduced to Brazil in or around early 2014, possibly from the Caribbean region. MAIN CONCLUSIONS Our study describes the early detection of a newly introduced and rapidly-expanding DENV2 virus lineage in Brazil.


Subject(s)
Humans , Genetic Variation , Genomics , Dengue/virology , Dengue Virus/genetics , Phylogeny , Brazil , RNA, Viral/genetics , Genotype
5.
Rev. Soc. Bras. Med. Trop ; 53: e20190439, 2020. tab, graf
Article in English | LILACS | ID: biblio-1101443

ABSTRACT

Abstract INTRODUCTION: DENV-2 is the cause of most dengue epidemics worldwide and is associated with severe cases. METHODS: We investigated arboviruses in 164 serum samples collected from patients presenting with clinical symptoms of dengue fever and 152 mosquito pools. RESULTS: We detected the Asian II genotype of DENV-2 in humans and mosquitoes. Our results confirmed the circulation of the Asian II genotype in Brazil, in addition to the prevalent Asian/American genotype. CONCLUSIONS: The detection of Asian II genotype of DENV-2 in mosquito pools collected in a forest park may be related to a spillback event of human dengue virus.


Subject(s)
Humans , Animals , Dengue/virology , Dengue Virus/genetics , Culicidae/virology , Phylogeny , Seasons , Brazil , RNA, Viral/genetics , Polymerase Chain Reaction , Genotype , Culicidae/classification
6.
Mem. Inst. Oswaldo Cruz ; 115: e200287, 2020. tab, graf
Article in English | LILACS | ID: biblio-1154869

ABSTRACT

BACKGROUND The heat-labile nature of Dengue virus (DENV) in serum samples must be considered when applying routine diagnostic tests to avoid issues that could impact the accuracy of test results with direct implications for case management and disease reporting. OBJECTIVES To check if pre-analytical variables, such as storage time and temperature, have an impact on the accuracy of the main routine diagnostic tests for dengue. METHODS Virus isolation, reverse transcription real-time polymerase chain reaction (RT-PCR) and NS1 enzyme-linked immunosorbent assay (ELISA) were evaluated using 84 samples submitted to different pre-analytical conditions. FINDINGS Sensitivity and negative predictive value were directly affected by sample storage conditions. RT-PCR and virus isolation showed greater dependence on well-conserved samples for an accurate diagnosis. Interestingly, even storage at -30ºC for a relatively short time (15 days) was not adequate for accurate results using virus isolation and RT-PCR tests. On the other hand, NS1 ELISA showed no significant reduction in positivity for aliquots tested under the same conditions as in the previous tests. MAIN CONCLUSIONS Our results support the stability of the NS1 marker in ELISA diagnosis and indicate that the accuracy of routine tests such as virus isolation and RT-PCR is significantly affected by inadequate transport and storage conditions of serum samples.


Subject(s)
Humans , Immunologic Tests/methods , Enzyme-Linked Immunosorbent Assay/methods , Viral Nonstructural Proteins/immunology , Reverse Transcriptase Polymerase Chain Reaction/methods , Dengue/diagnosis , Dengue Virus/isolation & purification , Antigens, Viral/blood , Predictive Value of Tests , Sensitivity and Specificity , Viral Nonstructural Proteins/genetics , Dengue/blood , Dengue/virology , Dengue Virus/genetics , Dengue Virus/immunology , Antibodies, Viral/blood , Antigens, Viral/immunology
7.
Rev. Soc. Bras. Med. Trop ; 52: e20190060, 2019. graf
Article in English | LILACS | ID: biblio-1041555

ABSTRACT

Abstract INTRODUCTION: In this study, we aimed to identify DENV-2 subtypes in Aedes aegypti pools collected between 2011 and 2017 in a rural area of Northern Cordoba, Colombia ("La Balsa"). METHODS: RT-PCR was performed to analyze the capsid/pre-membrane region (C-PrM). Sequencing and phylogenetic bayesian inference using reference DENV-2 sequences were performed. RESULTS: Twelve pools that tested positive for DENV-2 were characterized based on the C-PrM region and grouped under the Asian/American clade. CONCLUSIONS: This study is the first to report the DENV-2 Asian-American subtype in a rural area of Cordoba region, which is associated with severe dengue and local epidemics.


Subject(s)
Animals , Phylogeny , Aedes/virology , Dengue/virology , Dengue Virus/classification , Dengue Virus/genetics , Mosquito Vectors/virology , Serotyping , Bayes Theorem , Colombia/epidemiology , Severe Dengue , Reverse Transcriptase Polymerase Chain Reaction , Dengue/epidemiology , Dengue Virus/isolation & purification , Serogroup
8.
Braz. j. infect. dis ; 22(4): 257-272, July-Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-974229

ABSTRACT

ABSTRACT Dengue, the most prevalent arboviral disease worldwide, is caused by any of the four dengue virus (DENV) serotypes that co-circulate constantly in hyperendemic areas such as Medellin (Colombia), and these serotypes are transmitted by mosquitoes of the genus Aedes. In this study, we evaluated the replicative capacity of strains isolated in Medellin between 2003 and 2007 in C6/36 cells and in colonies of Aedes aegypti collected during 2010-2011 from high or low-incidence areas within the same city. The phylogenetic analysis grouped isolates according to the predominant genotypes found in the Americas, and the in vitro characterization showed differences in the morphological changes induced by the isolates of each of the isolated serotypes compared to the reference serotypes. In vitro replicative capacity studies demonstrated that genomic copy number increased at four days post-infection and that cell viability decreased significantly compared to the control for all serotypes. The largest number of genomic copies in C6/36 was produced by DENV-2, followed by DENV-1 and DENV-4; DENV-3 produced the smallest number of genomic copies and had the smallest negative effect on cell viability. Finally, differences in the in vivo replication of intercolonial serotypes between the Rockefeller colony and the field colonies and among the intracolonial serotypes were found. The replication of DENV-2 at 7 and 14 days in both high- and low-incidence colonies was higher than that of the other serotypes, and replication of DENV-3 in the mosquito colonies was the most stable on the days evaluated. Our results support the notion that replication and, possibly, DENV transmission and severity depend on many factors, including serotype and vector characteristics.


Subject(s)
Humans , Animals , Virus Replication , Aedes/virology , Dengue/transmission , Dengue Virus/physiology , Insect Vectors/virology , Phylogeny , Urban Population , Colombia , Dengue/virology , Dengue Virus/isolation & purification , Dengue Virus/genetics , Serogroup
9.
Rev. Soc. Bras. Med. Trop ; 51(2): 168-173, Mar.-Apr. 2018. graf
Article in English | LILACS | ID: biblio-897058

ABSTRACT

Abstract INTRODUCTION: Dengue virus (DENV) is the most important arthropod-borne viral disease worldwide with an estimated 50 million infections occurring each year. METHODS: In this study, we present a flow cytometry assay (FACS) for diagnosing DENV, and compare its results with those of the non-structural protein 1 (NS1) immunochromatographic assay and reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: All three assays identified 29.1% (39/134) of the patients as dengue-positive. The FACS approach and real-time RT-PCR detected the DENV in 39 and 44 samples, respectively. On the other hand, the immunochromatographic assay detected the NS1 protein in 40.1% (56/134) of the patients. The Cohen's kappa coefficient analysis revealed a substantial agreement among the three methods. CONCLUSIONS: The FACS approach may be a useful alternative for dengue diagnosis and can be implemented in public and private laboratories.


Subject(s)
Humans , Leukocytes, Mononuclear/virology , Dengue/diagnosis , Dengue Virus/genetics , Dengue Virus/immunology , Antibodies, Viral/blood , Cell Separation , Chromatography, Affinity , Sensitivity and Specificity , Viral Nonstructural Proteins/genetics , Reverse Transcriptase Polymerase Chain Reaction , Flow Cytometry , Fluorescence
10.
Rev. chil. infectol ; 35(2): 176-183, abr. 2018. tab, graf
Article in Spanish | LILACS | ID: biblio-959427

ABSTRACT

Resumen Introducción: La viremia plasmática es un factor cuyo rol en la gravedad de la infección por el virus del dengue se ha discutido ampliamente en los últimos años, siendo hallados resultados divergentes en los múltiples contextos evaluados. Métodos: Se realizó una revisión sistemática de la literatura utilizando las bases de datos Scopus, EBSCOhost, SpringerLink, Lilacs y Scielo. Se consideraron para su inclusión en la revisión estudios que evaluaran la relación entre la carga viral en plasma y las manifestaciones clínicas o la gravedad de la enfermedad. Resultados: Se obtuvieron 80 referencias en la búsqueda inicial, posterior a la aplicación de los criterios de inclusión/exclusión fueron seleccionados 20 artículos. En el estudio de este fenómeno son múltiples los parámetros desde los cuales debe ser evaluada la viremia, no sólo desde su magnitud, sino también desde su duración post-defervescencia y el día en el que se reporta el valor máximo, entre otros. Discusión: Los resultados de los estudios indican que las características de la viremia pueden jugar un rol de importancia que, junto con otros factores del contexto viral (serotipo del virus, tipo de infección) y del paciente (edad, genotipo, comorbilidades, etc), pueden determinar el desenlace clínico de la infección.


Background: Plasma viremia is a factor whose role in the severity of dengue virus infection has been widely discussed in recent years, with divergent results found in the multiple contexts evaluated. Methods: A systematic review of the literature using the Scopus, EBSCOhost, SpringerLink, Lilacs and Scielo databases was conducted. For inclusion in the review there were considered studies that evaluated the relationship between plasma viral load and clinical manifestations or severity of the disease. Results: We obtained 80 references in the initial search, after the application of the inclusion / exclusion criteria 20 articles were selected. In the study of this phenomenon there are multiple parameters from which viremia should be evaluated, not only from its magnitude, but also from the post-defervescence duration and the day in which the maximum value is reported, among others. Discussion: The results of the studies indicate that the characteristics of viremia may play an important role that, along with other factors of the viral (virus serotype, type of infection) and patient context (age, genotype, comorbidities, etc.), determine the clinical outcome of the infection.


Subject(s)
Humans , Male , Viremia/virology , Viral Load , Dengue/diagnosis , Dengue/virology , Dengue Virus/isolation & purification , Viremia/genetics , Severity of Illness Index , Dengue Virus/genetics , Serogroup , Genotype , Antibodies, Viral
11.
Mem. Inst. Oswaldo Cruz ; 113(5): e170393, 2018. tab, graf
Article in English | LILACS | ID: biblio-894924

ABSTRACT

BACKGROUND The genus Flavivirus includes a variety of medically important viruses, including dengue virus (DENV) and Zika virus (ZIKV), which are most prevalent in Brazil. Because the clinical profile of patients affected by different DENV serotypes or ZIKV may be similar, the development of new methods that facilitate a rapid and accurate diagnosis is crucial. OBJECTIVES The current study aimed to develop an improved reverse transcription-polymerase chain reaction (RT-PCR) protocol for universal detection of flaviviruses by using semi-nested primers that discriminate between DENV serotypes and ZIKV. METHODS The bioinformatics workflow adopted for primer design included: (1) alignment of 1,442 flavivirus genome sequences, (2) characterisation of 27 conserved regions, (3) generation of a primer set comprising 77 universal primers, and (4) selection of primer pairs with greatest coverage and specificity. Following primer design, the reaction was validated in vitro. The same approach was applied to the design of primers specific for DENV and ZIKV, using a species-specific sequence database. FINDINGS The new assay amplified an 800-806 nt variable region of the NS5 gene and allowed discrimination of virtually all flavivirus species using reference-sequence comparison. The 800-806 nt fragment was validated as a template for a semi-nested multiplex PCR using five additional primers for the detection of DENV and ZIKV. These primers were designed to generate amplicons of different sizes, allowing differentiation of the four serotypes of DENV, and ZIKV using agarose gel electrophoresis. MAIN CONCLUSIONS The bioinformatics pipeline allowed efficient primer design, making it possible to identify the best targets within the coding region of the NS5 protein. The multiplex system proved effective in differentiation of DENV1-4 and ZIKV on a 2% agarose gel. The possibility of discriminating DENV serotypes and ZIKV in the same reaction provided a faster result consuming less sample. In addition, this simplified approach ensured the reduction of the cost per analysis.


Subject(s)
Viral Nonstructural Proteins , Dengue Virus/genetics , Zika Virus , DNA Primers/genetics , Computational Biology/methods , Reverse Transcriptase Polymerase Chain Reaction
12.
Mem. Inst. Oswaldo Cruz ; 113(8): e180036, 2018. graf
Article in English | LILACS | ID: biblio-1040599

ABSTRACT

The dengue virus (DENV), of the genus Flavivirus (Flaviviridae), has four antigenically distinct serotypes, of which DENV-3 is classified into five genotypes. Here, we describe the detection of DENV-3 genotype I in sera of a Brazilian patient travelling from Singapore to Rio de Janeiro, Brazil, by using multiplex real-time RT-PCR, DNA sequencing of the whole envelope protein gene, and phylogenetic analysis. The virus shares ancestry with those identified in Bali, Indonesia, in 2015. It is possible that arboviruses such as Chikungunya ECSA genotype, DENV-4 genotype I, and Zika were introduced in Brazil from other continents during the multiple international events hosted by the country over the last four years, including World Youth Day, the Soccer World Cup, and the Summer Olympics.


Subject(s)
Humans , Dengue/virology , Dengue Virus/genetics , Zika Virus/genetics , Zika Virus Infection/virology , Communicable Diseases, Imported/virology , Genotype , Phylogeny , Genetic Variation , Brazil , Polymerase Chain Reaction , Sequence Analysis, DNA , Dengue Virus/isolation & purification , Serogroup
13.
Mem. Inst. Oswaldo Cruz ; 113(4): e170208, 2018. tab, graf
Article in English | LILACS | ID: biblio-1040593

ABSTRACT

The lack of an experimental animal model for the study of dengue pathogenesis is a limiting factor for the development of vaccines and drugs. In previous studies, our group demonstrated the susceptibility of BALB/c mice to infection by dengue virus (DENV) 1 and 2, and the virus was successfully isolated in several organs. In this study, BALB/c mice were experimentally infected intravenously with DENV-4, and samples of their saliva were collected. Viral RNA extracted from the saliva samples was subjected to qRT-PCR, with a detection limit of 0.002 PFU/mL. The presence of DENV-4 viral RNA was detected in the saliva of two mice, presenting viral titers of 109 RNA/mL. The detection of DENV RNA via saliva sampling is not a common practice in dengue diagnosis, due to the lower detection rates in human patients. However, the results observed in this study seem to indicate that, as in humans, detection rates of DENV RNA in mouse saliva are also low, correlating the infection in both cases. This study reports the first DENV detection in the saliva of BALB/c immunocompetent mice experimentally infected with non-neuroadapted DENV-4.


Subject(s)
Humans , Animals , Male , Mice , Saliva/virology , Dengue Virus/isolation & purification , RNA, Viral/isolation & purification , RNA, Viral/genetics , Immunocompromised Host , Viral Load/genetics , Reverse Transcriptase Polymerase Chain Reaction , Dengue Virus/genetics , Disease Models, Animal , Mice, Inbred BALB C
14.
Mem. Inst. Oswaldo Cruz ; 113(11): e170538, 2018. tab
Article in English | LILACS | ID: biblio-1040584

ABSTRACT

This study showed that laboratory markers of recent infection by dengue, Zika or chikungunya arboviruses were detected in the biological samples of approximately one-third of patients with encephalitis, myelitis, encephalomyelitis or Guillain-Barré syndrome, in a surveillance programme in Piauí state, Brazil, between 2015-2016. Fever and myalgia had been associated with these cases. Since in non-tropical countries most infections or parainfectious diseases associated with the nervous system are attributed to herpesviruses, enteroviruses, and Campylobacter jejuni, the present findings indicate that in tropical countries, arboviruses may now play a more important role and reinforce the need for their surveillance and systematic investigation in the tropics.


Subject(s)
Humans , Chikungunya virus/genetics , Chikungunya virus/immunology , Dengue Virus/genetics , Dengue Virus/immunology , Zika Virus/genetics , Zika Virus/immunology , Acute Disease , Reverse Transcriptase Polymerase Chain Reaction , Guillain-Barre Syndrome/diagnosis , Guillain-Barre Syndrome/virology , Encephalitis/diagnosis , Encephalitis/virology , Encephalomyelitis, Acute Disseminated/diagnosis , Encephalomyelitis, Acute Disseminated/virology , Enzyme-Linked Immunospot Assay , Myelitis, Transverse/diagnosis , Myelitis, Transverse/virology , Nervous System Diseases/diagnosis , Nervous System Diseases/virology
15.
Rev. chil. infectol ; 35(6): 658-668, 2018. tab, graf
Article in Spanish | LILACS | ID: biblio-990849

ABSTRACT

Resumen Introducción: Los virus del dengue y chikungunya son transmitidos por la hembra de los mosquitos Aedes aegypti y Aedes albopictus, ampliamente distribuidos en zonas tropicales y subtropicales, lo que facilita la co-infección. Objetivo: Determinar la magnitud, la distribución geográfica y el cuadro clínico de la co-infección por dengue y chikungunya. Material y Métodos: Revisión narrativa. Búsqueda en las bases de datos PubMed y Lilacs, utilizando los términos MeSH "Chikungunya", "CHIKV", "DENV", "Dengue" y "coinfection. Se incluyeron los artículos de los últimos 20 años. Resultados: Se incluyeron 45 artículos. El mayor reporte de co-infección fue en Asia seguido de África. En las Américas la información es limitada por la reciente circulación del chikungunya. La magnitud de la co-infección varió entre 0 y 31,9%. No se encontraron diferencias en la distribución de la co-infección por sexo y edad. El cuadro clínico de la mono-infección y la co-infección fue similar. Algunos reportes de caso exponen cuadros graves con afección del sistema nervioso central, manifestaciones hemorrágicas y enfermedad de Still. Conclusión: Las manifestaciones clínicas de la co-infección por dengue y chikungunya son similares a la mono-infección, situación que dificulta el diagnóstico y la medición de su magnitud.


Background: Dengue and chikungunya viruses are transmitted by the female Aedes aegypti and Aedes albopictus, which are widely distributed in tropical and subtropical areas, facilitating coinfection. Aim: To determine the magnitude, geographical distribution and clinical picture of dengue and chikungunya coinfection. Material and Methods: Narrative review. A search in the PubMed and Lilacs databases was made, using the MeSH terms "Chikungunya", "CHIKV", "DENV", "Dengue" and "coinfection. The articles of the last 20 years were included. Results: A total of 45 articles were included. The largest coinfection report was in Asia followed by Africa. In the Americas, the information is limited because of the recent circulation of chikungunya. The magnitude of coinfection varies between 0% and 31.9%. No differences were found in the distribution of coinfection by sex and age. The clinical picture of monoinfection and coinfection was similar. Some case reports show severe cases with central nervous system involvement, hemorrhagic manifestations and Still's disease. Conclusion: The clinical manifestations of coinfection by dengue and chikungunya viruses are similar to those due to monoinfection, which difficult the diagnosis and measurement of its magnitude.


Subject(s)
Humans , Animals , Dengue/virology , Coinfection/virology , Chikungunya Fever/virology , Severity of Illness Index , Chikungunya virus/genetics , Dengue/diagnosis , Dengue/mortality , Dengue/transmission , Dengue Virus/genetics , Coinfection/diagnosis , Coinfection/mortality , Coinfection/transmission , Chikungunya Fever/diagnosis , Chikungunya Fever/mortality , Chikungunya Fever/transmission , Mosquito Vectors , Genotype , Geography
16.
Mem. Inst. Oswaldo Cruz ; 112(12): 829-837, Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-894854

ABSTRACT

BACKGROUND Dengue viruses (DENV) are considered one of the most important emerging pathogens and dengue disease is a global health threat. The geographic expansion of dengue viruses has led to co-circulation of all four dengue serotypes making it imperative that new DENV control strategies be devised. OBJECTIVES Here we characterize dengue serotype-specific innate immune responses in Aedes aegypti and Aedes albopictus using DENV from Puerto Rico (PR). METHODS Ae. aegypti and Ae. albopictus were infected with dengue serotype 1 and 2 isolated from Puerto Rico. DENV infected mosquito samples were collected and temporal change in expression of selected innate immune response pathway genes analyzed by quantitative real time PCR. FINDINGS The Toll pathway is involved in anti-dengue response in Ae. aegypti, and Ae. albopictus. Infections with PR DENV- 1 elicited a stronger response from genes of the Toll immune pathway than PR DENV-2 in Ae. aegypti but in infected Ae. albopictus expression of Toll pathway genes tended to be similar between the serotypes. Two genes (a ribosomal S5 protein gene and a nimrod-like gene) from Ae. albopictus were expressed in response to DENV. MAIN CONCLUSIONS These studies revealed a role for antiviral genes in DENV serotype-specific interactions with DENV vectors, demonstrated that infections with DENV-2 can modulate the Toll immune response pathway in Ae. aegypti and elucidated candidate molecules that might be used to interfere with serotype specific vector-virus interactions.


Subject(s)
Animals , Aedes/classification , Aedes/virology , Dengue Virus/isolation & purification , Dengue Virus/genetics , Dengue Virus/immunology , Insect Vectors/classification , Insect Vectors/virology , Real-Time Polymerase Chain Reaction
17.
Mem. Inst. Oswaldo Cruz ; 112(7): 520-522, July 2017. tab, graf
Article in English | LILACS | ID: biblio-841817

ABSTRACT

This study aimed to detect dengue virus (DENV) serotypes in serum samples obtained in Matamoros Tamaulipas, Mexico, and to determine the concordance of conventional nested reverse transcriptase polymerase chain reaction (RT-PCR) and a serological test [enzyme-linked immunosorbent assay (ELISA NS1)]. Here, we detected mixed infections consisting of four serotypes of DENV. The most prevalent serotype was DENV-1, followed by DENV-4. This is the first report of DENV-4 in our region. Mixed infections were also detected in 21.5% of samples, and the predominant coinfection consisted of DENV-1 and DENV-2. Therefore, continuous epidemiological surveillance of DENV in this area is required to predict future forms of dengue heterologous infections and the effect of this on health care.


Subject(s)
Humans , Male , Enzyme-Linked Immunosorbent Assay , Polymerase Chain Reaction , RNA-Directed DNA Polymerase , Dengue/diagnosis , Dengue/virology , Dengue Virus/genetics , Serogroup , Antibodies, Viral/blood , Mexico
18.
Rev. Soc. Bras. Med. Trop ; 50(3): 379-382, May-June 2017. tab
Article in English | LILACS | ID: biblio-1041413

ABSTRACT

Abstract INTRODUCTION: The incidence of dengue has increased throughout the 2000s with a consequent global increase in atypical clinical forms. METHODS: This study reports a series of cases of neurological dengue out of 498 confirmed cases of laboratory dengue in Goiânia, Brazil. Cases were confirmed based on viral RNA detection via polymerase chain reaction or IgM antibody capture. RESULTS: Neurological symptoms occurred in 5.6% of cases, including paresthesia (3.8%), encephalitis (2%), encephalopathy (1%), seizure (0.8%), meningoencephalitis (0.4%), and paresis (0.4%). DENV-3 was the predominant circulating serotype (93%). CONCLUSIONS: We reported dengue cases with neurological manifestations in endemic area.


Subject(s)
Humans , Male , Female , Aged , Paresthesia/virology , Enzyme-Linked Immunosorbent Assay , Encephalitis, Viral/virology , Dengue/complications , Dengue/epidemiology , Meningoencephalitis/virology , Paresthesia/epidemiology , Brazil/epidemiology , RNA, Viral/genetics , Polymerase Chain Reaction , Encephalitis, Viral/epidemiology , Dengue Virus/genetics , Dengue Virus/immunology , Meningoencephalitis/epidemiology , Middle Aged , Antibodies, Viral/blood
19.
Rev. chil. infectol ; 34(2): 143-148, abr. 2017. ilus
Article in Spanish | LILACS | ID: biblio-844458

ABSTRACT

Dengue is one of the most important mosquito-borne diseases, and its incidence has increased at an alarming rate in recent years, becoming a real public health problem. Currently, there is no vaccine or medication or proper treatment for dengue control. Considering this situation, it is necessary to prioritize the search for new alternatives and strategies for dengue prevention and control, in order to reduce not only the economic burden of endemic countries, but also to improve the quality of life of patients. In this regard, a brief reflection on some aspects related to the search for new alternatives in Colombia is presented. This is focused on the use of microRNAs, which could be a new strategy with great therapeutic potential.


El dengue es una de las enfermedades más importantes transmitidas por mosquitos y su incidencia ha aumentado a un ritmo alarmante en los últimos años, al punto que se ha convertido en un verdadero problema de salud pública. Actualmente no existe ni vacuna, ni un medicamento o tratamiento adecuado para el control del dengue. Con dichos antecedentes, es necesario priorizar en la búsqueda de nuevas alternativas o estrategias de control y prevención del dengue con miras a disminuir no sólo la carga económica de los países endémicos, sino también a mejorar la calidad de vida de los pacientes. En este sentido, se presenta una breve reflexión sobre algunos aspectos relacionados con la búsqueda de nuevas alternativas en Colombia, enfocadas en el uso de los microARNs, que podrían constituir una nueva estrategia con un gran potencial terapéutico, dado que tendrían el potencial de contrarrestar algunas infecciones virales crónicas.


Subject(s)
Humans , Virus Replication/genetics , Dengue Virus/genetics , MicroRNAs/metabolism , Protein Biosynthesis , Colombia , MicroRNAs/genetics , Biomedical Research
20.
Mem. Inst. Oswaldo Cruz ; 112(4): 281-291, Apr. 2017. graf
Article in English | LILACS | ID: biblio-841788

ABSTRACT

BACKGROUND Dengue is considered one of the world’s most important mosquito-borne diseases. MicroRNAs (miRNAs) are small non-coding single-stranded RNAs that play an important role in the regulation of gene expression in eukaryotes. Although miRNAs possess antiviral activity against many mammalian-infecting viruses, their involvement in Dengue virus (DENV) replication remains poorly understood. OBJECTIVE To determine the role of miR-484 and miR-744 in DENV infection and to examine whether DENV infection alters the expression of both miRNAs. METHODS We used bioinformatics tools to explore the relationship between DENV and cellular miRNAs. We then overexpressed miR-484 or miR-744 in Vero cells to examine their role in DENV replication using flow cytometry, reverse transcriptase quantitative polymerase chain reaction (RT-qPCR), and western blotting. FINDINGS We found several cellular miRNAs that target a conserved region within the 3′ untranslated region (3′ UTR) of the genome of the four DENV serotypes and found that overexpression of miR-484 or miR-744 inhibits infection by DENV-1 to DENV-4. Furthermore, we observed that DENV RNA might be involved in the downregulation of endogenous miR-484 and miR-744. CONCLUSION Our study identifies miR-484 and miR-744 as two possible restriction host factors against DENV infection. However, further studies are needed to directly verify whether miR-484 and miR-744 both have an anti-DENV effect in vivo.


Subject(s)
Animals , Virus Replication/physiology , Virus Replication/genetics , Chlorocebus aethiops , Gene Expression Regulation/genetics , Blotting, Western , Polymerase Chain Reaction , Computational Biology , Untranslated Regions , Untranslated Regions/physiology , Dengue Virus/physiology , Dengue Virus/genetics , MicroRNAs/metabolism , Flow Cytometry
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