Simultaneous circulation of genotypes I and III of dengue virus 3 in Colombia

<p>Abstract</p> <p>Background</p> <p>Dengue is a major health problem in tropical and subtropical regions. In Colombia, dengue viruses (DENV) cause about 50,000 cases annually, 10% of which involve Dengue Haemorrhagic Fever/Dengue Shock Syndrome. The picture is similar in other surrounding countries in the Americas, with recent outbreaks of severe disease, mostly associated with DENV serotype 3, strains of the Indian genotype, introduced into the Americas in 1994.</p> <p>Results</p> <p>The analysis of the 3'end (224 bp) of the envelope gene from 32 DENV-3 strains recently recovered in Colombia confirms the circulation of the Indian genotype, and surprisingly the co-circulation of an Asian-Pacific genotype only recently described in the Americas.</p> <p>Conclusion</p> <p>These results have important implications for epidemiology and surveillance of DENV infection in Central and South America. Molecular surveillance of the DENV genotypes infecting humans could be a very valuable tool for controlling/mitigating the impact of the DENV infection.</p

Seroprevalence and Risk Factors Possibly Associated with Emerging Zoonotic Vaccinia Virus in a Farming Community, Colombia

In 2014, vaccinia virus (VACV) infections were identified among farmworkers in Caquetá Department, Colombia; additional cases were identified in Cundinamarca Department in 2015. VACV, an orthopoxvirus (OPXV) used in the smallpox vaccine, has caused sporadic bovine and human outbreaks in countries such as Brazil and India. In response to the emergence of this disease in Colombia, we surveyed and collected blood from 134 farmworkers and household members from 56 farms in Cundinamarca Department. We tested serum samples for OPXV antibodies and correlated risk factors with seropositivity by using multivariate analyses. Fifty-two percent of farmworkers had OPXV antibodies; this percentage decreased to 31% when we excluded persons who would have been eligible for smallpox vaccination. The major risk factors for seropositivity were municipality, age, smallpox vaccination scar, duration of time working on a farm, and animals having vaccinia-like lesions. This investigation provides evidence for possible emergence of VACV as a zoonosis in South America.https://scienti.minciencias.gov.co/cvlac/visualizador/generarCurriculoCv.do?cod_rh=0000318507https://scholar.google.com.co/citations?user=cU2KyT4AAAAJ&hl=enhttps://scienti.minciencias.gov.co/gruplac/jsp/visualiza/visualizagr.jsp?nro=00000000008981https://orcid.org/0000-0002-8093-054

Phylogenetic history demonstrates two different lineages of dengue type 1 virus in Colombia

Background: Dengue Fever is one of the most important viral re-emergent diseases affecting about 50 million people around the world especially in tropical and sub-tropical countries. In Colombia, the virus was first detected in the earliest 70′s when the disease became a major public health concern. Since then, all four serotypes of the virus have been reported. Although most of the huge outbreaks reported in this country have involved dengue virus serotype 1 (DENV-1), there are not studies about its origin, genetic diversity and distribution. Results: We used 224 bp corresponding to the carboxyl terminus of envelope (E) gene from 74 Colombian isolates in order to reconstruct phylogenetic relationships and to estimate time divergences. Analyzed DENV-1 Colombian isolates belonged to the formerly defined genotype V. Only one virus isolate was clasified in the genotype I, likely representing a sole introduction that did not spread. The oldest strains were closely related to those detected for the first time in America in 1977 from the Caribbean and were detected for two years until their disappearance about six years later. Around 1987, a split up generated 2 lineages that have been evolving separately, although not major aminoacid changes in the analyzed region were found. Conclusion: DENV-1 has been circulating since 1978 in Colombia. Yet, the phylogenetic relationships between strains isolated along the covered period of time suggests that viral strains detected in some years, although belonging to the same genotype V, have different recent origins corresponding to multiple re-introduction events of viral strains that were circulating in neighbor countries. Viral strains used in the present study did not form a monophyletic group, which is evidence of a polyphyletic origin. We report the rapid spread patterns and high evolution rate of the different DENV-1 lineages

Evolution in spatially mixed host environments increases divergence for evolved fitness and intrapopulation genetic diversity in RNA viruses

Virus populationsmay be challenged to evolve in spatially heterogeneous environments, such asmixtures of host cells that pose differing selection pressures. Spatial heterogeneitymay select for evolved polymorphisms, wheremultiple virus subpopulations coexist by specializing on a narrow subset of the available hosts. Alternatively, spatial heterogeneitymay 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 cellmixtures. 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. Despitemeasurable 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 ofminority variants was significant only when we considered variants with a frequency of at least 10 per cent in the population. The number of lower-frequencyminority variants per population did not significantly correlate with divergence

Efficient Method for Molecular Characterization of the 5′ and 3′ Ends of the Dengue Virus Genome

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&prime; and 3&prime; ends of the untranslated regions (UTR) commonly requires specific approaches for completion and corroboration. The present study aimed to characterize the 5&prime; and 3&prime; ends of dengue virus types 1 to 4. The 5&prime; and 3&prime; 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&prime; 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&prime; 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&prime; and 3&prime; 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

Detección y caracterización del virus de la anemia infecciosa aviar en Colombia

Objetivo. identificar el virus de la anemia infecciosa aviar (chicken anemia virus, CAV) en granjas avícolas y aves de traspatio en Antioquia, Colombia. Materiales y métodos. Se tomaron muestras de sangre y plumas de gallinas ponedoras; en cada granja se eligieron tres aves de seis edades diferentes (1, 15, 30, 60, 90 y 120 días de edad). También se obtuvieron muestras de aves de traspatio ubicadas cerca de las granjas estudiadas. Se realizó ELISA y PCR para el análisis de las muestras. Resultados. Mediante PCR, el 84% de las aves resultaron positivas al CAV en sangre total y el 66% en muestras de plumas. El 60% de las aves de traspatio dieron positivo en sangre y el 40% en folículo de pluma. Mediante ELISA, el 22% de las aves de las granjas avícolas presentó títulos de anticuerpos altos y el 19% moderados. En las aves de traspatio, el 43% presentó títulos de anticuerpos altos y 29% moderados. Además, los resultados de la prueba de RFLP y la secuenciación mostraron que el virus circulante encontrado en este estudio era diferente del de la cepa vacunal Cux-1 utilizada en el país. Conclusiones. El CAV está presente en Colombia en aves comerciales como de traspatio. Según los hallazgos, un alto porcentaje de las aves dieron positivo para la detección viral, aunque el número de aves positivas por anticuerpos fue bajo. Se requiere determinar las características del virus circulante para explicar la respuesta de anticuerpos obtenida.Objective. identify the presence of chicken anemia virus (CAV) in poultry farms and backyard chickens from Antioquia, Colombia. Materials and Methods. Blood and feather samples were taken from laying chickens; in each farm, three birds of six different ages (1, 15, 30, 60, 90, and 120 days old) were chosen randomly. Backyard chicken samples were also obtained near the research farms. We used serology and molecular techniques to analyze the samples. Results. By PCR, the 84% of the birds were positive in whole blood and 66% were positive in feather samples. The 60% 2/12 Rev MVZ Córdoba. 2023. Mayo-Agosto; 28(2):e2835 https://doi.org/10.21897/rmvz.2835 Folleco-Villarreal et al - El virus de la anemia infecciosa aviar en Colombia of backyard chickens tested were positive in blood and 40% in feather follicle. By serology, the 22% of the poultry farm birds presented high antibody titers and 19% moderate antibody titers. In the backyard chickens, 43% of them presented high antibody titers and 29% moderate antibody titers. In addition, results from the RFLP test and sequencing showed that the circulating virus found in this study was different from the Cux-1 vaccine strain used in Colombia. Conclusions. CAV is present in Colombia in both commercial and backyard chickens. According to the findings, a high percentage of the birds tested positive for viral detection, whereas the number of birds that tested positive for antibodies was low. Thus, the characteristics of the circulating virus need to be determined to explain the antibody response observed in this study

Phylogenetic history demonstrates two different lineages of dengue type 1 virus in Colombia

Abstract Background Dengue Fever is one of the most important viral re-emergent diseases affecting about 50 million people around the world especially in tropical and sub-tropical countries. In Colombia, the virus was first detected in the earliest 70's when the disease became a major public health concern. Since then, all four serotypes of the virus have been reported. Although most of the huge outbreaks reported in this country have involved dengue virus serotype 1 (DENV-1), there are not studies about its origin, genetic diversity and distribution. Results We used 224 bp corresponding to the carboxyl terminus of envelope (E) gene from 74 Colombian isolates in order to reconstruct phylogenetic relationships and to estimate time divergences. Analyzed DENV-1 Colombian isolates belonged to the formerly defined genotype V. Only one virus isolate was clasified in the genotype I, likely representing a sole introduction that did not spread. The oldest strains were closely related to those detected for the first time in America in 1977 from the Caribbean and were detected for two years until their disappearance about six years later. Around 1987, a split up generated 2 lineages that have been evolving separately, although not major aminoacid changes in the analyzed region were found. Conclusion DENV-1 has been circulating since 1978 in Colombia. Yet, the phylogenetic relationships between strains isolated along the covered period of time suggests that viral strains detected in some years, although belonging to the same genotype V, have different recent origins corresponding to multiple re-introduction events of viral strains that were circulating in neighbor countries. Viral strains used in the present study did not form a monophyletic group, which is evidence of a polyphyletic origin. We report the rapid spread patterns and high evolution rate of the different DENV-1 lineages.</p

Genotyping of dengue virus from infected tissue samples embedded in paraffin

Dengue has become one of the vector-borne diseases that affect humans worldwide. In Latin American countries, Colombia is historically one of the most affected by epidemics of this flavivirus. The underreporting of signs and symptoms of probable cases of dengue, the lack of characterization of the serotypes of the infection, and the few detailed studies of postmortem necropsies of patients are among other conditions that have delayed progress in the knowledge of the pathogenesis of the disease. This study presents the results of fragment sequencing assays on paraffin-embedded tissue samples from fatal DENV cases during the 2010 epidemic in Colombia. We found that the predominant serotype was DENV-2, with the Asian/American genotype of lineages 1 and 2. This work is one of the few reports of the circulating genotypes of dengue during the 2010 epidemic in Colombia, one of the most lethal dates in the country's history.Instituto Nacional de Salu