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1.
Viruses ; 15(4)2023 04 13.
Article in English | MEDLINE | ID: mdl-37112933

ABSTRACT

The family Tymoviridae comprises positive-sense RNA viruses, which mainly infect plants. Recently, a few Tymoviridae-like viruses have been found in mosquitoes, which feed on vertebrate sources. We describe a novel Tymoviridae-like virus, putatively named, Guachaca virus (GUAV), isolated from Culex pipiens and Culex quinquefasciatus species of mosquitoes and collected in the rural area of Santa Marta, Colombia. After a cytopathic effect was observed in C6/36 cells, RNA was extracted and processed through the NetoVIR next-generation sequencing protocol, and data were analyzed through the VirMAP pipeline. Molecular and phenotypic characterization of the GUAV was achieved using a 5'/3' RACE, transmission electron microscopy, amplification in vertebrate cells, and phylogenetic analysis. A cytopathic effect was observed in C6/36 cells three days post-infection. The GUAV genome was successfully assembled, and its polyadenylated 3' end was corroborated. GUAV shared only 54.9% amino acid identity with its closest relative, Ek Balam virus, and was grouped with the latter and other unclassified insect-associated tymoviruses in a phylogenetic analysis. GUAV is a new member of a family previously described as comprising plant-infecting viruses, which seem to infect and replicate in mosquitoes. The sugar- and blood-feeding behavior of the Culex spp., implies a sustained contact with plants and vertebrates and justifies further studies to unravel the ecological scenario for transmission.


Subject(s)
Culex , Culicidae , Tymoviridae , Animals , Phylogeny , Colombia
2.
Infect Dis Now ; 53(3): 104654, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36709865

ABSTRACT

INTRODUCTION: Unvaccinated individuals in endemic areas with proven enzootic transmission of Yellow fever virus are at risk of infection due to a dramatic shift in the epidemiology of the disease over recent years. For this reason, epidemiological surveillance and laboratory confirmation of cases have become mandatory. OBJECTIVE: To develop and test a control RNA for YFV detection through real-time RT-PCR. METHODS: A 437-bp insert containing the T7 promoter and the target sequences for two different in-house protocols was designed in the context of the pUC57 vector and obtained through gene synthesis. After T7-driven in vitro transcription, standard curves were developed for Log10 serial dilutions of the YFV control RNA with 8 replicates. RESULTS: A dynamic range of quantification of 10 orders of magnitude was observed with a limit of detection of 6.3 GCE/µL (95% CI, 2.6 to 139.4 GCE/µL). CONCLUSION: The plasmid construct is available for YFV molecular test validation on clinical, entomological, and epizootic samples.


Subject(s)
Yellow Fever , Yellow fever virus , Humans , Yellow fever virus/genetics , Yellow Fever/diagnosis , Yellow Fever/epidemiology , Reverse Transcription , Reverse Transcriptase Polymerase Chain Reaction , RNA
3.
Infect Genet Evol ; 95: 105038, 2021 11.
Article in English | MEDLINE | ID: mdl-34403832

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genetic diversity has the potential to impact the virus transmissibility and the escape from natural infection- or vaccine-elicited neutralizing antibodies. Here, representative samples from circulating SARS-CoV-2 in Colombia between January and April 2021, were processed for genome sequencing and lineage determination following the nanopore amplicon ARTIC network protocol and PANGOLIN pipeline. This strategy allowed us to identify the emergence of the B.1.621 lineage, considered a variant of interest (VOI) with the accumulation of several substitutions affecting the Spike protein, including the amino acid changes I95I, Y144T, Y145S and the insertion 146 N in the N-terminal domain, R346K, E484K and N501Y in the Receptor binding Domain (RBD) and P681H in the S1/S2 cleavage site of the Spike protein. The rapid increase in frequency and fixation in a relatively short time in Magdalena, Atlantico, Bolivar, Bogotá D.C, and Santander that were near the theoretical herd immunity suggests an epidemiologic impact. Further studies will be required to assess the biological and epidemiologic roles of the substitution pattern found in the B.1.621 lineage.


Subject(s)
Amino Acid Substitution , COVID-19/epidemiology , Genome, Viral , Mutation , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , COVID-19/transmission , COVID-19/virology , Colombia/epidemiology , Epidemiological Monitoring , Evolution, Molecular , High-Throughput Nucleotide Sequencing , Humans , Phylogeny , Phylogeography , Protein Domains , SARS-CoV-2/classification , SARS-CoV-2/pathogenicity , Severity of Illness Index
4.
Front Med (Lausanne) ; 8: 697605, 2021.
Article in English | MEDLINE | ID: mdl-34262921

ABSTRACT

COVID-19 pandemics has led to genetic diversification of SARS-CoV-2 and the appearance of variants with potential impact in transmissibility and viral escape from acquired immunity. We report a new and highly divergent lineage containing 21 distinctive mutations (10 non-synonymous, eight synonymous, and three substitutions in non-coding regions). The amino acid changes L249S and E484K located at the CTD and RBD of the Spike protein could be of special interest due to their potential biological role in the virus-host relationship. Further studies are required for monitoring the epidemiologic impact of this new lineage.

5.
Article in English | MEDLINE | ID: mdl-33787744

ABSTRACT

A few studies have carried out the taxonomic and molecular characterization of sylvatic mosquito species in Latin America, where some species have been incriminated as vectors for arboviruses and parasites transmission. The present study reports the molecular characterization of mosquito species in the Sierra Nevada de Santa Marta, a natural ecosystem in the Northern coast of Colombia. Manual capture methods were used to collect mosquitoes, and the specimens were identified via classical taxonomy. The COI marker was used for species confirmation, and phylogenetic analysis was performed using the neighbor-joining method, with the Kimura-2-Parameters model. Aedes serratus , Psorophora ferox , Johnbelkinia ulopus , Sabethes chloropterus , Sabethes cyaneus , Wyeomyia aporonoma , Wyeomyia pseudopecten , Wyeomyia ulocoma and Wyeomyia luteoventralis were identified. We assessed the genetic variability of mosquitoes in this area and phylogenetic reconstructions allowed the identification at the species level. Classical and molecular taxonomy demonstrated to be useful and complementary when morphological characteristics are not well preserved, or the taxonomic group is not represented in public molecular databases.


Subject(s)
Culicidae/genetics , Phylogeny , Rainforest , Animals , Colombia , DNA Barcoding, Taxonomic , Ecosystem , Mosquito Vectors
6.
Emerg Infect Dis ; 26(12): 2854-2862, 2020 12.
Article in English | MEDLINE | ID: mdl-33219646

ABSTRACT

Coronavirus disease (COVID-19) in Colombia was first diagnosed in a traveler arriving from Italy on February 26, 2020. However, limited data are available on the origins and number of introductions of COVID-19 into the country. We sequenced the causative agent of COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), from 43 clinical samples we collected, along with another 79 genome sequences available from Colombia. We investigated the emergence and importation routes for SARS-CoV-2 into Colombia by using epidemiologic, historical air travel, and phylogenetic observations. Our study provides evidence of multiple introductions, mostly from Europe, and documents >12 lineages. Phylogenetic findings validate the lineage diversity, support multiple importation events, and demonstrate the evolutionary relationship of epidemiologically linked transmission chains. Our results reconstruct the early evolutionary history of SARS-CoV-2 in Colombia and highlight the advantages of genome sequencing to complement COVID-19 outbreak investigations.


Subject(s)
COVID-19/epidemiology , COVID-19/virology , Genome, Viral , Genomics/methods , Phylogeny , SARS-CoV-2/genetics , Colombia/epidemiology , Humans , Reproducibility of Results
7.
Infect Genet Evol ; 85: 104557, 2020 11.
Article in English | MEDLINE | ID: mdl-32950697

ABSTRACT

SARS-CoV-2 is a new member of the genus Betacoronavirus, responsible for the COVID-19 pandemic. The virus crossed the species barrier and established in the human population taking advantage of the spike protein high affinity for the ACE receptor to infect the lower respiratory tract. The Nucleocapsid (N) and Spike (S) are highly immunogenic structural proteins and most commercial COVID-19 diagnostic assays target these proteins. In an unpredictable epidemic, it is essential to know about their genetic variability. The objective of this study was to describe the substitution frequency of the S and N proteins of SARS-CoV-2 in South America. A total of 504 amino acid and nucleotide sequences of the S and N proteins of SARS-CoV-2 from seven South American countries (Argentina, Brazil, Chile, Ecuador, Peru, Uruguay, and Colombia), reported as of June 3, and corresponding to samples collected between March and April 2020, were compared through substitution matrices using the Muscle algorithm. Forty-three sequences from 13 Colombian departments were obtained in this study using the Oxford Nanopore and Illumina MiSeq technologies, following the amplicon-based ARTIC network protocol. The substitutions D614G in S and R203K/G204R in N were the most frequent in South America, observed in 83% and 34% of the sequences respectively. Strikingly, genomes with the conserved position D614 were almost completely replaced by genomes with the G614 substitution between March to April 2020. A similar replacement pattern was observed with R203K/G204R although more marked in Chile, Argentina and Brazil, suggesting similar introduction history and/or control strategies of SARS-CoV-2 in these countries. It is necessary to continue with the genomic surveillance of S and N proteins during the SARS-CoV-2 pandemic as this information can be useful for developing vaccines, therapeutics and diagnostic tests.


Subject(s)
Amino Acid Substitution , COVID-19/diagnosis , SARS-CoV-2/classification , Viral Proteins/genetics , Coronavirus Nucleocapsid Proteins/genetics , High-Throughput Nucleotide Sequencing , Humans , Phylogeny , SARS-CoV-2/genetics , Sequence Analysis, RNA , South America , Spike Glycoprotein, Coronavirus/genetics
8.
Infect Genet Evol ; 84: 104390, 2020 10.
Article in English | MEDLINE | ID: mdl-32505692

ABSTRACT

The COVID-19 pandemic caused by SARS-CoV-2 is a public health problem unprecedented in the recent history of humanity. Different in-house real-time RT-PCR (rRT-PCR) methods for SARS-CoV-2 diagnosis and the appearance of genomes with mutations in primer regions have been reported. Hence, whole-genome data from locally-circulating SARS-CoV-2 strains contribute to the knowledge of its global variability and the development and fine tuning of diagnostic protocols. To describe the genetic variability of Colombian SARS-CoV-2 genomes in hybridization regions of oligonucleotides of the main in-house methods for SARS-CoV-2 detection, RNA samples with confirmed SARS-CoV-2 molecular diagnosis were processed through next-generation sequencing. Primers/probes sequences from 13 target regions for SARS-CoV-2 detection suggested by 7 institutions and consolidated by WHO during the early stage of the pandemic were aligned with Muscle tool to assess the genetic variability potentially affecting their performance. Finally, the corresponding codon positions at the 3' end of each primer, the open reading frame inspection was identified for each gene/protein product. Complete SARS-CoV-2 genomes were obtained from 30 COVID-19 cases, representative of the current epidemiology in the country. Mismatches between at least one Colombian sequence and five oligonucleotides targeting the RdRP and N genes were observed. The 3' end of 4 primers aligned to the third codon position, showed high risk of nucleotide substitution and potential mismatches at this critical position. Genetic variability was detected in Colombian SARS-CoV-2 sequences in some of the primer/probe regions for in-house rRT-PCR diagnostic tests available at WHO COVID-19 technical guidelines; its impact on the performance and rates of false-negative results should be experimentally evaluated. The genomic surveillance of SARS-CoV-2 is highly recommended for the early identification of mutations in critical regions and to issue recommendations on specific diagnostic tests to ensure the coverage of locally-circulating genetic variants.


Subject(s)
Betacoronavirus/genetics , Coronavirus Infections/epidemiology , Genome, Viral , Pandemics , Pneumonia, Viral/epidemiology , RNA, Viral/genetics , Viral Proteins/genetics , Base Sequence , Betacoronavirus/pathogenicity , COVID-19 , COVID-19 Testing , COVID-19 Vaccines , Clinical Laboratory Techniques , Colombia/epidemiology , Coronavirus Infections/diagnosis , Coronavirus Infections/pathology , Coronavirus Infections/virology , Genetic Variation , High-Throughput Nucleotide Sequencing , Humans , Molecular Epidemiology , Open Reading Frames , Pneumonia, Viral/diagnosis , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Real-Time Polymerase Chain Reaction/methods , SARS-CoV-2 , Sequence Alignment
9.
Viruses ; 12(5)2020 04 29.
Article in English | MEDLINE | ID: mdl-32365696

ABSTRACT

Dengue is a mosquito-borne disease that is of major importance in public health. Although it has been extensively studied at the molecular level, sequencing of the 5' and 3' ends of the untranslated regions (UTR) commonly requires specific approaches for completion and corroboration. The present study aimed to characterize the 5' and 3' ends of dengue virus types 1 to 4. The 5' and 3' ends of twenty-nine dengue virus isolates from acute infections were amplified through a modified protocol of the rapid amplification cDNA ends approach. For the 5' end cDNA synthesis, specific anti-sense primers for each serotype were used, followed by polyadenylation of the cDNA using a terminal transferase and subsequent PCR amplification with oligo(dT) and internal specific reverse primer. At the 3' end of the positive-sense viral RNA, an adenine tail was directly synthetized using an Escherichia coli poly(A) polymerase, allowing subsequent hybridization of the oligo(dT) during cDNA synthesis. The incorporation of the poly(A) tail at the 5' and 3' ends of the dengue virus cDNA and RNA, respectively, allowed for successful primer hybridization, PCR amplification and direct sequencing. This approach can be used for completing dengue virus genomes obtained through direct and next-generation sequencing methods.


Subject(s)
Dengue Virus/genetics , Dengue/virology , RNA, Viral/genetics , 3' Untranslated Regions , 5' Untranslated Regions , Dengue Virus/metabolism , Genome, Viral , Humans , Polyadenylation , RNA, Viral/metabolism
10.
Emerg Infect Dis ; 26(3): 601-605, 2020 03.
Article in English | MEDLINE | ID: mdl-32091366

ABSTRACT

In March 2015, a patient in Colombia with HIV/AIDS was hospitalized for disseminated ulcers after milking cows that had vesicular lesions on their udders. Vaccinia virus was detected, and the case met criteria for progressive vaccinia acquired by zoonotic transmission. Adherence to an optimized antiretroviral regimen resulted in recovery.


Subject(s)
HIV Infections , Vaccinia virus/isolation & purification , Vaccinia/diagnosis , Acquired Immunodeficiency Syndrome , Adult , Animals , Antiretroviral Therapy, Highly Active , Antiviral Agents/therapeutic use , Colombia , Humans , Male , Vaccinia/drug therapy , Vaccinia/transmission , Zoonoses/virology
11.
Microbiol Resour Announc ; 8(46)2019 Nov 14.
Article in English | MEDLINE | ID: mdl-31727724

ABSTRACT

A Zika virus (ZIKV) strain was isolated from an acute febrile patient during the Zika epidemics in Colombia. The strain was intraperitoneally inoculated into BALB/c mice, and 7 days postinoculation, neurological manifestations and ZIKV infection in the brain were demonstrated. The reported genome sequence is highly related to strains circulating in the Americas.

12.
J Virol Methods ; 271: 113677, 2019 09.
Article in English | MEDLINE | ID: mdl-31195032

ABSTRACT

Dengue virus (DENV) is the causative agent of one of the most important febrile illnesses worldwide. Four DENV serotypes are responsible for a broad clinical spectrum of the disease. Positive controls are costly and required for the validation of molecular test results of DENV serotyping. In this study, we describe the in silico design of the qDENV-Control plasmid with the target sequences to oligonucleotides and probes widely used for DENV serotyping, and the subsequent production of qDENV Control RNA by T7-driven run-off in vitro transcription. The qDENV Control RNA was successfully used to validate the positive and negative DENV serotyping results, allowing its incorporation in routine in-house protocols for virologic surveillance. This Control RNA allowed the absolute quantification of viral RNA copies from unknown samples as required in several fundamental studies.


Subject(s)
Dengue Virus/classification , RNA, Viral/analysis , RNA, Viral/genetics , Computer Simulation , DNA Primers/genetics , DNA Probes/genetics , Dengue/virology , Humans , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Sensitivity and Specificity , Serogroup , Serotyping , Transcription, Genetic
13.
Virol J ; 16(1): 62, 2019 05 08.
Article in English | MEDLINE | ID: mdl-31068191

ABSTRACT

Dengue is hyperendemic in Colombia, where a cyclic behavior of serotype replacement leading to periodic epidemics has been observed for decades. This level of endemicity favors accumulation of dengue virus genetic diversity and could be linked to disease outcome. To assess the genetic diversity of dengue virus type 2 in Colombia, we sequenced the envelope gene of 24 virus isolates from acute cases of dengue or severe dengue fever during the period 2013-2016. The phylogenetic analysis revealed the circulation of the Asian-American genotype of dengue virus type 2 in Colombia during that period, the intra-genotype variability leading to divergence in two recently circulating lineages with differential geographic distribution, as well as the presence of nonsynonymous substitutions accompanying their emergence and diversification.


Subject(s)
Dengue Virus/genetics , Dengue/virology , Genetic Variation , Genotype , RNA, Viral/blood , Adolescent , Adult , Biological Specimen Banks , Child , Child, Preschool , Colombia/epidemiology , Dengue/epidemiology , Female , High-Throughput Nucleotide Sequencing , Humans , Male , Middle Aged , Phylogeny , RNA, Viral/genetics , Retrospective Studies , Serogroup , Viral Envelope Proteins/genetics , Young Adult
14.
Rev. salud pública ; 20(6): 785-790, nov.-dic. 2018. graf
Article in Spanish | LILACS | ID: biblio-1020860

ABSTRACT

RESUMEN La reciente ocurrencia de infecciones por el virus vaccinia en animales y humanos en distintos lugares de la geografía colombiana, sumadas a otras por éste y por otros virus pertenecientes al género Orthopoxvirus (familia Poxviridae), ocurridas en algunos países de Suramérica, África, Asia y Europa se convierten en evidencia de la inminente emergencia y re-emergencia de este género, con características biológicas y epidemiológicas que le confieren gran interés para la salud pública del mundo, como lo fue en el pasado una de sus especies representativas: el virus de la viruela. Esta emergencia y re-emergencia parecen estar relacionadas con la suspensión en las décadas de los 70s y 80s de las campañas de vacunación contra la viruela, las cuales; insospechadamente estuvieron protegiendo a la población, no únicamente contra este virus, sino contra otros del mismo género. En el presente artículo se hace una revisión de la biología y epidemiología de los principales miembros del género Orthopoxvirus, su presentación clínica, antecedentes históricos, contexto social, e impacto en la salud pública mundial en el pasado, presente y a futuro.(AU)


ABSTRACT The recent occurrence of vaccinia virus infections in humans and animals in Colombia, together with that reported for this and other species of the genus Orthopoxvirus in some South American, African, Asian and European countries, is supporting evidence of the emergence and re-emergence of the genus. This fact has become of great interest for public health around the world due to its biological and an epidemiological features, as was in the past the variola virus, one of its representatives. The emergence and re-emergence of the genus Orthopoxvirus may be a consequence of stopping vaccination against the variola virus in the 1970s and 1980s. This vaccination unsuspectedly induced cross-protective immunity to other species of that genus. This is a review of the history, biology and epidemiology of the main species of the genus Orthopoxvirus, together with its clinical presentation, social context and public health impact in the past, present and future.(AU)


Subject(s)
Humans , Poxviridae , Variola virus , Communicable Diseases, Emerging/epidemiology , Colombia/epidemiology
15.
Rev Salud Publica (Bogota) ; 20(6): 778-783, 2018 11 01.
Article in Spanish | MEDLINE | ID: mdl-33206905

ABSTRACT

The recent occurrence of vaccinia virus infections in humans and animals in Colombia, together with that reported for this and other species of the genus Orthopoxvirus in some South American, African, Asian and European countries, is supporting evidence of the emergence and re-emergence of the genus. This fact has become of great interest for public health around the world due to its biological and an epidemiological features, as was in the past the variola virus, one of its representatives. The emergence and re-emergence of the genus Orthopoxvirus may be a consequence of stopping vaccination against the variola virus in the 1970s and 1980s. This vaccination unsuspectedly induced cross-protective immunity to other species of that genus. This is a review of the history, biology and epidemiology of the main species of the genus Orthopoxvirus, together with its clinical presentation, social context and public health impact in the past, present and future.


La reciente ocurrencia de infecciones por el virus vaccinia en animales y humanos en distintos lugares de la geografía colombiana, sumadas a otras por éste y por otros virus pertenecientes al género Orthopoxvirus (familia Poxviridae), ocurridas en algunos países de Suramérica, África, Asia y Europa se convierten en evidencia de la inminente emergencia y re-emergencia de este género, con características biológicas y epidemiológicas que le confieren gran interés para la salud pública del mundo, como lo fue en el pasado una de sus especies representativas: el virus de la viruela. Esta emergencia y re-emergencia parecen estar relacionadas con la suspensión en las décadas de los 70s y 80s de las campañas de vacunación contra la viruela, las cuales; insospechadamente estuvieron protegiendo a la población, no únicamente contra este virus, sino contra otros del mismo género. En el presente artículo se hace una revisión de la biología y epidemiología de los principales miembros del género Orthopoxvirus, su presentación clínica, antecedentes históricos, contexto social, e impacto en la salud pública mundial en el pasado, presente y a futuro.


Subject(s)
Poxviridae Infections/epidemiology , Viral Zoonoses/epidemiology , Animals , Colombia/epidemiology , Communicable Diseases, Emerging/epidemiology , Cross Reactions , Disease Eradication/history , Disease Outbreaks/history , Global Health , History, 18th Century , History, 19th Century , History, 20th Century , History, 21st Century , History, Ancient , Humans , Poxviridae Infections/history , Poxviridae Infections/immunology , Public Health , Smallpox/history , Smallpox/prevention & control , Smallpox Vaccine , Social Determinants of Health , Vaccination , Vaccinia/epidemiology , Viral Zoonoses/history
16.
Emerg Infect Dis ; 23(4): 649-653, 2017 04.
Article in English | MEDLINE | ID: mdl-28322708

ABSTRACT

During 2014, cutaneous lesions were reported in dairy cattle and farmworkers in the Amazon Region of western Colombia. Samples from 6 patients were analyzed by serologic and PCR testing, and results demonstrated the presence of vaccinia virus and pseudocowpox virus. These findings highlight the need for increased poxvirus surveillance in Colombia.


Subject(s)
Poxviridae Infections/virology , Pseudocowpox Virus/isolation & purification , Vaccinia virus/isolation & purification , Vaccinia/virology , Adolescent , Adult , Animals , Cattle , Child , Colombia/epidemiology , Farmers , Female , Humans , Male , Middle Aged , Phylogeny , Poxviridae Infections/epidemiology , Vaccinia/epidemiology , Vaccinia virus/genetics , Young Adult
17.
Virus Evol ; 2(1): vev022, 2016 Jan.
Article in English | MEDLINE | ID: mdl-27774292

ABSTRACT

Virus populations may be challenged to evolve in spatially heterogeneous environments, such as mixtures of host cells that pose differing selection pressures. Spatial heterogeneity may select for evolved polymorphisms, where multiple virus subpopulations coexist by specializing on a narrow subset of the available hosts. Alternatively, spatial heterogeneity may select for evolved generalism, where a single genotype dominates the virus population by occupying a relatively broader host niche. In addition, the extent of spatial heterogeneity should influence the degree of divergence among virus populations encountering identical environmental challenges. Spatial heterogeneity creates environmental complexity that should increase the probability of differing adaptive phenotypic solutions, thus producing greater divergence among replicate virus populations, relative to counterparts evolving in strictly homogeneous host environments. Here, we tested these ideas using experimental evolution of RNA virus populations grown in laboratory tissue culture. We allowed vesicular stomatitis virus (VSV) lineages to evolve in replicated environments containing BHK-21 (baby hamster kidney) cells, HeLa (human epithelial) cells, or spatially heterogeneous host cell mixtures. Results showed that generalist phenotypes dominated in evolved virus populations across all treatments. Also, we observed greater variance in host-use performance (fitness) among VSV lineages evolved under spatial heterogeneity, relative to lineages evolved in homogeneous environments. Despite measurable differences in fitness, consensus Sanger sequencing revealed no fixed genetic differences separating the evolved lineages from their common ancestor. In contrast, deep sequencing of evolved VSV populations confirmed that the degree of divergence among replicate lineages was correlated with a larger number of minority variants. This correlation between divergence and the number of minority variants was significant only when we considered variants with a frequency of at least 10 per cent in the population. The number of lower-frequency minority variants per population did not significantly correlate with divergence.

18.
Biomédica (Bogotá) ; 36(supl.2): 25-34, ago. 2016. ilus, graf, mapas, tab
Article in Spanish | LILACS | ID: lil-794014

ABSTRACT

Introducción. El virus del chikungunya, perteneciente al género Alphavirus de la familia Togaviridae, es un virus ARN de 11,8 kb, de cadena sencilla y polaridad positiva, transmitido por Aedes spp . Se han identificado tres genotipos a nivel mundial: el de Asia, el del este-centro-sur de África ( East/Central/South African, ECSA) y el de África occidental ( West African, WA). La fiebre del chikungunya es una enfermedad febril aguda, acompañada principalmente de inflamación en las articulaciones y erupción cutánea. Después de su aparición en las Américas en el 2013, los primeros casos en Colombia ocurrieron en septiembre de 2014 y hasta junio del 2015 se habían notificado 399.932 casos. Objetivo. Identificar el genotipo o los genotipos responsables de la primera epidemia por el virus del chikungunya en Colombia y la variabilidad genética asociada a su dispersión en el territorio nacional. Materiales y métodos. Se seleccionaron muestras de suero de pacientes con síntomas indicativos de fiebre del chikungunya durante 2014 y 2015. Se hizo una transcripción inversa seguida de reacción en cadena de la polimerasa del gen E1, así como su secuenciación, análisis filogenético y análisis de evolución adaptativa. Resultados. Se demostró la presencia exclusiva del genotipo de Asia en Colombia. Se registró un promedio de 0,001 sustituciones de bases por sitio, una identidad de 99,7 a 99,9 % en los nucleótidos y de 99,9 % en los aminoácidos entre las secuencias colombianas y las secuencias de las Américas. Los análisis de evolución adaptativa indicaron una fuerte selección purificadora en el gen E1 . Conclusiones. Se determinó la circulación del genotipo de Asia del virus del chikungunya como la causa de la primera epidemia en Colombia. Es necesario continuar con la vigilancia de genotipos, con el fin de detectar posibles cambios en la epidemiología, la eficacia ( fitness ) viral y la patogenia del virus.


Introduction: Chikungunya virus (CHIKV) is a single-stranded positive sense RNA virus that belongs to the Alphavirus genus of the family Togaviridae. Its genome is 11.8 kb in length, and three genotypes have been identified worldwide: Asian, East/Central/South African (ECSA) and West African. Chikungunya fever is an acute febrile disease transmitted by Aedes spp . that usually presents with polyarthralgia and cutaneous eruption. Following introduction of the virus to the Americas in 2013, the first cases in Colombia occurred in September of 2014, and they reached a cumulative total of 399,932 cases by June of 2015. Objective: To identify the genotype or genotypes responsible for the current epidemic in Colombia and to describe the genetic variability of the virus in the country. Materials and methods: Serum samples from patients presenting with symptoms compatible with Chikungunya fever during 2014-2015 were selected for the study. RT-PCR products of the E1 gene from these samples were used for sequencing and subsequent phylogenetic and adaptive evolution analyses. Results: The study identified only the presence of the Asian genotype in Colombia. Comparing the Colombian sequences with other sequences from the Americas revealed an average of 0.001 base substitutions per site, with 99.7% and 99.9% nucleotide identity and 99.9% amino acid identity. The adaptive evolution analysis indicated that the E1 gene is under strong purifying selection. Conclusions: The first epidemic of Chikunguya fever in Colombia was caused by the circulation of the virus Asian genotype. Further genotypic surveillance of the virus in Colombia is required to detect possible changes in its epidemiology, fitness and pathogenicity.


Subject(s)
Chikungunya virus , Colombia , Genotype , Phylogeny , Surveillance in Disasters
19.
Intervirology ; 59(5-6): 275-282, 2016.
Article in English | MEDLINE | ID: mdl-28641298

ABSTRACT

Dengue viruses (DENV) have become the most important arthropod-borne viruses, causing dengue and severe dengue fever in at least 50-100 million cases each year, mainly in tropical and subtropical countries. During recent years, important advances in the molecular biology concerning the life cycle of these viruses have allowed the manipulation and generation of recombinant viruses and replicons with multiple applications, mainly in viral biology and the screening of antiviral compounds. In the present study, we describe the construction of an enhanced green fluorescent protein-bearing DENV replicon under the control of the cytomegalovirus immediate early promoter. Following a rational in silico design and cloning by standard molecular biology techniques, a reporter DENV-2 replicon and a replication-deficient mutant were constructed, and characterized by confocal microscopy and real-time RT-PCR. The results showed successful transcription, translation, and autonomous viral RNA replication of the DENV replicon from its DNA clone. This novel DENV replicon will allow the study of viral replication and testing of antiviral candidates without the need for in vitro transcription.

20.
Biomedica ; 36(0): 25-34, 2015 Oct 23.
Article in English | MEDLINE | ID: mdl-27622790

ABSTRACT

INTRODUCTION: Chikungunya virus (CHIKV) is a single-stranded positive sense RNA virus that belongs to the Alphavirus genus of the family Togaviridae. Its genome is 11.8 kb in length, and three genotypes have been identified worldwide: Asian, East/Central/South African (ECSA) and West African. Chikungunya fever is an acute febrile disease transmitted by Aedes spp. that usually presents with polyarthralgia and cutaneous eruption. Following introduction of the virus to the Americas in 2013, the first cases in Colombia occurred in September of 2014, and they reached a cumulative total of 399,932 cases by June of 2015.  OBJECTIVE: To identify the genotype or genotypes responsible for the current epidemic in Colombia and to describe the genetic variability of the virus in the country.  MATERIALS AND METHODS: Serum samples from patients presenting with symptoms compatible with Chikungunya fever during 2014-2015 were selected for the study. RT-PCR products of the E1 gene from these samples were used for sequencing and subsequent phylogenetic and adaptive evolution analyses.  RESULTS: The study identified only the presence of the Asian genotype in Colombia. Comparing the Colombian sequences with other sequences from the Americas revealed an average of 0.001 base substitutions per site, with 99.7% and 99.9% nucleotide identity and 99.9% amino acid identity. The adaptive evolution analysis indicated that the E1 gene is under strong purifying selection.  CONCLUSIONS: The first epidemic of Chikunguya fever in Colombia was caused by the circulation of the virus Asian genotype. Further genotypic surveillance of the virus in Colombia is required to detect possible changes in its epidemiology, fitness and pathogenicity.


Subject(s)
Aedes/virology , Alphavirus Infections/epidemiology , Chikungunya Fever/virology , Chikungunya virus , Alphavirus Infections/pathology , Americas , Animals , Chikungunya Fever/epidemiology , Colombia , Disease Outbreaks , Genotype , Humans
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