First whole-genome chikungunya virus sequence detected in mosquitoes during the 2025 Foshan outbreak: evidence of field vector infection and transmission potential in China

作者：Xinyu Zhou, Xiaoxue Xie, Wenhao Wang, Heting Gao, Kai Wang, Xiaohui Liu, Xiaoli Chen, Yuting Jiang, Haotian Yu, Dan Xing, Teng Zhao, Chunxiao Li · 发表于：Infectious Diseases of Poverty · 年份：2025 · DOI：10.1186/s40249-025-01383-9 · 被引用次数：11 · 研究领域：Mosquito-borne diseases and control、Malaria Research and Control、Invertebrate Immune Response Mechanisms

BACKGROUND: Since July 2025, an outbreak of mosquito-borne chikungunya fever has occurred in Foshan City, Guangdong Province, China. This was the second large-scale local outbreak in China after the one that occurred in Dongguan City, Guangdong Province, in 2010. As of 23 August, more than 10,000 human cases had been reported. This study aims to investigate mosquito infection and viral genomic characteristics during the Foshan outbreak. METHODS: Adult Aedes albopictus were collected using BioGents Sentinel trap in three hotspot towns (Beijiao, Chencun and Lecong). Mosquitoes were morphologically identified and pooled by species, sex and environment type. Each pool was homogenized, and the homogenate was clarified by centrifugation; and the supernatant was used for viral RNA isolation. The isolated RNA was screened using CHIKV RT-qPCR. Positive pools underwent Sanger sequencing and whole-genome sequencing. The CHIKV lineage and mutational profiles were inferred using maximum likelihood phylogenetic analysis and comparison with human- and mosquito-derived genomes. RESULTS: Over 11 days of trapping, 2803 mosquitoes were captured. 1569 (55.97%) female Ae. albopictus were divided into 77 pools and 9.09% (7/77) of these pools were CHIKV-positive. The minimum infection rate (MIR, per 1000 females) for local Ae. albopictus was 4.46, while the MIR for residences in Lecong Town was the highest at 9.17 per 1000 females. The MIR for parklands was slightly higher than for residences (4.60...