Li Man, Zeng Fen, Chang Wei, Zheng Mengyuan, Chen Xiaojuan, Wu Ziying, Liu Li, Xia Xueshan, Feng Yue
Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China.
Yunnan Provincial Key Laboratory of Public Health and Biosafety, Kunming Medical University, Kunming, Yunnan, China.
J Infect Dis. 2025 Aug 11. doi: 10.1093/infdis/jiaf422.
Dengue fever has become a significant epidemic in South and Southeast Asia. Recently, Yunnan Province in southwestern China, which borders these regions, has also experienced a significant outbreak. This study aims to investigate the genetic diversity of the dengue virus (DENV) and identify potential sources of transmission in Xishuangbanna, Yunnan Province in 2024.
In 2024, we investigated 321 suspected cases of dengue fever in Yunnan Province. We screened dengue fever patients using a combination of DENV NS1 antigen and Pan-qPCR methods, and performed serotype typing using specific qPCR. We also performed phylogenetic and molecular clock analyses to understand the genotypes and transmission sources.
DENV infection was detected in 101 of 321 specimens. Serotype and genotype analysis were performed on 88 of the 98 positive samples. The results showed that 81 cases belonged to the cosmopolitan genotype and cosmopolitan_asian-pacific subtype of DENV serotype 2 (DENV-2), while only 1 case was classified as genotype I and subtype 1L of DENV serotype 1 (DENV-1). Notably, samples within the cosmopolitan_asian-pacific subtype were primarily divided into two distinct lineages. Further analysis of whole genome sequences, focusing on phylogenetic history and spatiotemporal dynamics, indicated that lineage-1 likely originated in Thailand, while lineage-2 may have originated in Cambodia. In addition, we analyzed all available DENV-2 sequences from Yunnan in the GenBank database and found that DENV-2 genotypes in the Xishuangbanna region were more diverse and complex.
This study identifies two new lineages of cosmopolitan DENV-2 in Yunnan, originating from Thailand and Cambodia, respectively.
登革热已成为南亚和东南亚的一种重大流行病。最近，与这些地区接壤的中国西南部云南省也经历了一次重大疫情爆发。本研究旨在调查2024年云南省西双版纳地区登革热病毒（DENV）的遗传多样性，并确定潜在的传播来源。
2024年，我们对云南省321例登革热疑似病例进行了调查。我们使用DENV NS1抗原和泛qPCR方法相结合的方式对登革热患者进行筛查，并使用特异性qPCR进行血清型分型。我们还进行了系统发育和分子钟分析，以了解基因型和传播来源。
在321份标本中，检测到101份DENV感染。对98份阳性样本中的88份进行了血清型和基因型分析。结果显示，81例属于DENV血清型2（DENV-2）的世界基因型和世界-亚太亚型，而只有1例被归类为DENV血清型1（DENV-1）的基因型I和1L亚型。值得注意的是，世界-亚太亚型内的样本主要分为两个不同的谱系。对全基因组序列的进一步分析，重点关注系统发育历史和时空动态，表明谱系1可能起源于泰国，而谱系2可能起源于柬埔寨。此外，我们分析了GenBank数据库中来自云南的所有可用DENV-2序列，发现西双版纳地区的DENV-2基因型更加多样和复杂。
本研究在云南鉴定出两种新的世界DENV-2谱系，分别起源于泰国和柬埔寨。
