Developing new COVID-19 vaccine against the variants is urgently needed rather than boosters: A longitudinal cohort study. Issue 2 (February 2023) - Xu, Qiu-Yan; Zheng, Xin-Qi; Jia, Zhi-Juan; Wu, Meng-Juan; Liu, Yan-Yun; Liu, Li-Li; Lin, Li-Rong; Yang, Tian-Ci