Regular and booster vaccination with inactivated vaccines enhance the neutralizing activity against Omicron variant both in the breakthrough infections and vaccinees. Issue 4 (April 2022) - YangYang; Gong, Xiaohua; Yang, Liuqing; Li, Jie; Zhang, Jiaqi; Wei, Lanlan; Ye, Guoguo; Tang, Yimin; Jiang, Yujing; Li, Jianhuan; Lin, Yuanlong; Wang, Fuxiang; et al.