A medical worker takes a swab sample from a resident for nucleic acid test in Changning District of east China's Shanghai, April 1, 2022. (Photo: Xinhua)

BEIJING, April 4 (Xinhua) -- The number of COVID-19 vaccine doses administered on the Chinese mainland grew by around 2.36 million from the previous day, bringing the total to nearly 3.28 billion on Sunday, data from the National Health Commission showed Monday.