BEIJING, Jan. 20 (Xinhua) -- More than 15 million doses of COVID-19 vaccine have been administered in China since the country launched its vaccination program in December last year, China's health authorities said Wednesday.

After vaccinating key population groups, including medical personnel, transportation workers and workers at border ports, China will push forward mass vaccination at a steady pace, said Wang Bin, an official with the National Health Commission, at a press conference.

To ensure the vaccination program progresses smoothly, the country's health authorities have sent groups of medical experts to help regional authorities develop practical vaccination plans, said Wang.

In addition, the vaccination procedures have been strictly standardized and full precautions are taken, said Wang, adding that the recipients' health conditions are checked, their identities verified and the validity of the doses confirmed in accordance with procedure.