Kids head for the observation area after receiving COVID-19 vaccine at a vaccination site in Pingxiang City, south China's Guangxi Zhuang Autonomous Region, Nov. 16, 2021. (Xinhua/Cao Yiming)

BEIJING, Feb. 18 (Xinhua) -- The number of COVID-19 vaccine doses administered on the Chinese mainland grew by around 6.23 million on Thursday, with the total number now exceeding 3.06 billion, data from the National Health Commission showed Friday.