Phylogenetic analysis and transmission networks highlight the role of older adults in the transmission of HIV-1 in northern Zhejiang, China. - Chen, Wanjun; Fan, Qin; Cheng, Wei; Zhang, Jiafeng; He, Lin; Jiang, Jun; Liu, Xiaoqi; Zhu, Xiaojuan; Xing, Hui; Feng, Yi; Zhong, Ping; Pan, Xiaohong; et al. (Virology Journal, 2025)