China's COVID-19 vaccine output could exceed 3 billion by year-end - official

China's output of COVID-19 vaccines could reach more than 3 billion doses by the end of 2021, a National Health Commission official said on Saturday.

Zheng Zhongwei, who also heads a team coordinating the country's COVID-19 vaccine development projects, made the comment during an industry event in the city of Chengdu in southwestern China's Sichuan province.