Analysis of the viral molecular characteristics in a dengue fever outbreak in Jiangsu province in 2023
10.3760/cma.j.cn112866-20241128-00167
- VernacularTitle:2023年江苏省一起登革热疫情的病毒分子特征分析
- Author:
Yuanfang QIN
1
;
Nan ZHANG
;
Qian ZHEN
;
Zhifeng LI
;
Hao JU
;
Liguo ZHU
;
Jianguang FU
Author Information
1. 江苏省疾病预防控制中心，南京 210009
- Publication Type:Journal Article
- Keywords:
Dengue virus type 1;
Whole genome sequencing;
Genotyping;
Molecular characteristics
- From:
Chinese Journal of Experimental and Clinical Virology
2025;39(1):81-85
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the molecular characteristics of the virus in a local outbreak of dengue fever in Jiangsu province in 2023, and to provide a basis for the prevention and control of the outbreak.Methods:Serum samples were collected from suspected dengue patients in the acute phase of the outbreak for virus detection and serotyping by real-time fluorescence quantitative RT-PCR (RT-qPCR). Positive specimens were amplified with full-length genomic fragments and subjected to second-generation sequencing and related evolutionary analyses.Results:Four confirmed cases of dengue were found in Changzhou city, Jiangsu province, from October 18 to 21, 2023, with epidemiological association between the cases, which was recognized as a dengue outbreak. The serum RT-qPCR result of the four cases were all dengue type 1, and the whole genome sequences of three of the cases were obtained. The evolutionary tree of the E gene and the whole genome showed that the three sequences were located in the 3rd branch of the 1-I genotype, which is similar to the genotype 1-I. The genome-wide sequences of the E gene and the genome-wide evolution tree showed that the three sequences were located in the 3rd branch of the 1-I genotype, which is similar to the genome-wide genotype 1-Ⅰ. The E gene and the genome-wide evolutionary tree showed that all three sequences were located on branch 3 of genotype 1-Ⅰ, with high sequence similarity to the dengue virus epidemic strains in Guangdong and Yunnan provinces in 2023. Amino acid variant site analysis showed that there were 16 branch-specific amino acid site changes in the sequences of the three cases, among which the structural proteins, C protein and prM protein, had one variant site each, E protein had two, and the non-structural proteins had the largest number of NS5 variant sites (9).Conclusions:The local outbreak in Jiangsu was caused by dengue fever type 1 virus, with high nucleotide sequence similarity to strains from other regions of China, and amino acid site alterations.
