On March 15, the joint prevention and control mechanism of the State Council held a press conference, inviting Li Bin, vice director of the National Health Commission, and relevant officials of the Ministry of Industry and Information Technology and the Food and Drug Administration to introduce the relevant situation of the promotion of COVID-19 vaccination, and answering questions from reporters.

At the meeting, Li Bin, deputy director of the National Health Commission, said that as of March 14, 64.98 million people had been vaccinated with COVID-19 vaccine.

As of March 10, China's State Food and Drug Administration (SFDA) has conditionally approved four nCOVID-19 vaccines in China, respectively:

COVID-19 Inactivated Vaccine (Vero Cells) from SINOPHARM Beijing Institute of Biological Products Co., Ltd.

COVID-19 Inactivated Vaccine "CoronaVac" from Sinovac Research & Development Co., Ltd.

COVID-19 Inactivated Vaccine (Vero Cell) from SINOPHARM Wuhan Institute of Biological Products Co., Ltd.

Recombinant COVID-19 Vaccine (Adenovirus Type 5 Vector) from CanSino Biologics Inc.

Four vaccines are on the market with conditions and are being vaccinated among key groups nationwide.

The two vaccines made by SINOPHARM Beijing Institute of Biological Products Co., Ltd. and SINOPHARM Wuhan Institute of Biological Products Co., Ltd. as well as the vaccine made by Sinovac Research & Development Co., Ltd. are all inactivated vaccines with two doses of immunization.

Sinovac Research & Development Co., Ltd. said the research and development process of the inactivated vaccine is mainly through the culture of the virus on the cell matrix, and then use physical or chemical methods to make the virus lose its ability to replicate and infect, but at the same time to maintain the integrity of its antigen, inoculation of the human body so that the recipient of immune response. In short, it kills the virus, but allows it to retain some of its characteristics, allowing it to trigger an immune response when it enters the body.

CanSino 's adenovirus vector vaccine requires a single dose. Data from clinical trials show that cellular immunity peaks 14 days after vaccination, and humoral immunity peaks 28 days after vaccination, suggesting that cellular immunity plays a significant role.