Speakers
Description
Dengue virus (DENV) is a significant public health concern in Colombia. Since a large outbreak in 2019, the departments of Risaralda and Valle del Cauca have experienced increased incidence of arboviral disease. Phylogeographic tools are critical to understanding DENV diversity, persistence, and spread across Colombia. Therefore, this study analyzed plasma samples from individuals with acute/severe symptoms consistent with DENV infection to determine the phylogenetic and spatiotemporal dynamics of circulating DENV strains in two nearby Colombian departments. Metagenomic and amplicon-based sequencing of whole viral genomes confirmed the circulation of DENV1 genotype V in Risaralda and Valle del Cauca between 2019 and 2022. Bayesian phylogeographic analysis revealed three distinct clades, confirming the ongoing recirculation of different lineages in each region. The sequences' most recent common ancestor (MRCA) circulated in December 1997, which shows that the identified clades are the product of the circulating diversity due to in-situ evolution. Each clades had common ancestors with sequences isolated from other Colombian departments. Clade A contained one sequence from each department, the MRCA of these sequences circulated in 2018 and the clade share a MRCA in 2013 with a sequence from Cundinamarca. Clade B contained 16 sequences from Valle del Cauca and the TMRCA between the sequences was calculated in 2018. MRCA of this clade and Santander sequences was estimated in 2007. Finally, Clade C contained 6 sequences from Risaralda. The MRCA of these sequences circulated in 2018 and the clade shared a MRCA in 2015 with sequences from Antioquia. Non-synonymous substitutions relative to the TMRCA were identified in structural proteins and non-structural proteins, though they were distributed differently amongst clades. Characterization of DENV1 genotype V
circulation in Colombia highlights the role of genomic surveillance in identifying new lineages of inter-department migration that could impact outbreak management and public health.
