At the press conference of joint prevention and control mechanism in the State Council on the 21st, Mi Feng, spokesman of the National Health and Wellness Commission, introduced that recently, China began to carry out COVID-19 vaccination for some key people engaged in imported cold chain, port quarantine, fresh market, transportation, medical disease control and other work.

China has laid out five technical routes to simultaneously promote vaccine research and development. According to the statistics of the World Health Organization as of December 2, at present, 15 vaccines have entered clinical trials in China, of which 5 vaccines have entered phase III clinical trials, and the vaccines that have entered clinical trials have covered all technical routes in China. Zheng Zhongwei, head of the working group of the vaccine research and development special class of the scientific research group of the State Council Joint Prevention and Control Mechanism and director of the National Health Commission Medical and Health Science and Technology Development Research Center, said: "In the world, we have the most vaccines entering the Phase III clinical trial, and the research and development of COVID-19 vaccine in our country is in the first phalanx in the world."

Zheng Zhongwei said that during the emergency use of COVID-19 vaccine, more than 60,000 vaccinators had been to overseas high-risk areas, and no serious infection was reported. The data on the effectiveness of the vaccine need to be analyzed at the end of phase III clinical trials or the results of mid-term blindness. However, the clinical trial data of Phase I and Phase II provide some effective reference indicators, such as neutralizing antibodies, which can show that COVID-19 vaccine in China has good safety and effectiveness.

Wang Huaqing, chief expert of immunization program of China CDC, introduced in detail the immune mechanism that plays a role after vaccination: COVID-19 vaccine can specifically identify the invading pathogen, form immune memory, and quickly produce antibodies when encountering the same pathogen, so as to eliminate the pathogen and achieve the preventive effect. "If there is an opportunity for vaccination, the public should plant all kinds." Wang Huaqing said that the main time for COVID-19 vaccine to take effect is two weeks after the second dose of vaccine, which will produce better immune effect. At the same time, the efficacy of vaccine protection has a great relationship with the vaccination rate. When the vaccination rate in the population reaches a very high level, the immune barrier is established.

Who is not suitable for COVID-19 vaccination? What preparations need to be made before vaccination? What are the precautions during vaccination?

Wang Huaqing said that before vaccination with COVID-19 vaccine, the public should first understand the matters in the vaccine instructions, including taboos and other precautions. At the same time, it is necessary to understand the inoculation process, including the appointment method of local inoculation points and inoculation preparation. Wang Huaqing suggested that people with fever, patients with chronic diseases, patients with acute diseases and pregnant women should not be vaccinated with COVID-19 vaccine.

Because the research and development of vaccines in COVID-19 is relatively short, there is no research result on simultaneous vaccination of COVID-19 vaccine and other vaccines, so it is impossible to determine the safety and immune effect of simultaneous vaccination of two different types of vaccines. Therefore, it is not recommended to vaccinate two different types of vaccines at the same time in Wang Huaqing. (Reporter Shen Shaotie)