# Unraveling the Genomic Evolution of Dengue Virus Serotype 1: A Case Study from Yantai, China

## TL;DR

This study traces the genomic evolution of Dengue Virus Serotype 1 in China, revealing its spread and stability despite the SARS-CoV-2 pandemic.

## Contribution

The study provides new insights into the genomic evolution and population dynamics of DENV1 in China using metatranscriptomic sequencing.

## Key findings

- The identified DENV1 sequence is closely related to a 2023 Guangzhou sequence, with divergence estimated around 2019.
- The DENV1 strain belongs to genotype I and has been spreading in Southeast Asia and China since 2007.
- The DENV1 population has remained stable and unaffected by the SARS-CoV-2 pandemic.

## Abstract

In August 2023, we identified a case of dengue fever in Yantai City, which was imported from Xishuangbanna, China. To investigate its evolutionary history and population dynamics, we utilized the metatranscriptomic method to obtain the virus’ whole genome sequence. Together with 367 selected dengue virus whole genome sequences from the NCBI database, we constructed a time-scaled Maximum Clade Credibility (MCC) tree. We found that our sequence exhibited a high homology with a sequence of DENV1 (OR418422.1) uploaded by the Guangzhou Center for Disease Control and Prevention in 2023, with an estimated divergence time around 2019 (95% HPD: 2017–2023), coinciding with the emergence of SARS-CoV-2. The DENV strain obtained in this study belongs to genotype I of DENV1. Its ancestors experienced a global epidemic around 2005 (95% HPD: 2002–2010), and its progeny strains have spread extensively in Southeast Asia and China since around 2007 (95% HPD: 2006–2011). The Bayesian skyline plot indicates that the current population of DENV1 has not been affected by SARS-CoV-2 and is expected to maintain stable transmission. Hence, it is imperative to track and monitor its epidemiological trends and genomic variations to prevent potential large-scale outbreaks in the post-SARS-CoV-2 era.