China News Service, Guangzhou, August 13 (Cai Minjie and Wang Shuhui) Starting on the 13th, Guangzhou citizens can make appointments for inoculation of recombinant new coronavirus vaccine (CHO cells) at vaccination points in various districts, which is commonly referred to as the "three injections" vaccine.

Liu Yunting, deputy chief physician of the Department of Infection Management of the Second People's Hospital of Guangdong Province, said that at present, people who are vaccinated with the recombinant protein vaccine of the new crown virus are still people aged 18 and over, including the elderly.

Vaccination is not recommended for people under 18 years of age.

  The large-scale vaccination of the new coronavirus vaccine is to build an immune barrier for the population and an important means to prevent and control the pneumonia epidemic caused by the new coronavirus.

On the same day, at the Guangzhou epidemic prevention and control press conference, Chen Bin, deputy director of the Guangzhou Municipal Health Commission, said that as of August 12, the city had received 30.01 million doses of new crown vaccine and 17.03 million people; 13.2 million people had completed it. The whole course of vaccination has a coverage rate of 70.7%.

  According to Liu Yunting, the composition of the vaccine is similar to that of the natural virus and has good safety.

A phase II clinical trial of recombinant protein subunit neocoronavirus vaccine in 18-59-year-old adults showed that after 2 doses of vaccine, the positive conversion rate of the true virus neutralizing antibody reached 83%, and after 3 doses, the true virus was neutralized The positive conversion rate of antibodies reached 97%, which was twice as much as the serum neutralizing antibody level of patients with COVID-19, and the positive conversion rate of RBD protein-binding antibodies reached 99%.

  Liu Yunting said that the principle of the recombinant new coronavirus vaccine (CHO cell) technology is similar to that of the mature hepatitis B CHO cell vaccine: it is to recombine the new coronavirus S protein receptor binding region (RBD) gene into the Chinese hamster ovary (CHO) cell gene. It is expressed in vitro to form RBD dimer, and aluminum hydroxide adjuvant is added to improve immunogenicity. It is injected into the human body to induce the human body to produce neutralizing antibodies to achieve the purpose of preventing infection.

  How many doses of recombinant new coronavirus vaccine need to be vaccinated, and how long are the intervals?

Liu Yunting stated that the recommended interval between two adjacent doses should be ≥4 weeks (28 days); the second dose should be completed within 8 weeks after the first dose; the third dose should be completed 6 times after the first dose as much as possible Complete within a month.

  Regarding the contraindications for people vaccinating the recombinant new coronavirus, Liu Yunting said that the contraindications include those who are known to be allergic to the vaccine, including those who are allergic to excipients; those who suffer from acute diseases, severe chronic diseases, acute episodes of chronic diseases, and fever; during pregnancy. Women; those suffering from uncontrolled epilepsy and other progressive neurological diseases.

  If I have received 1 dose of inactivated vaccine, can I change to the second dose of recombinant subunit vaccine? Liu Yunting said that it’s not possible at this time. “At this stage, it is recommended to use the same vaccine product to complete vaccination. In special circumstances such as the unavailability of vaccine supply or the recipient’s remote vaccination, the same vaccine product can be used to complete vaccination. The vaccine products of other manufacturers of different types have been vaccinated. The premise is that the two doses of vaccines must be of the same type (such as Beijing Biotech and Kexing Zhongwei), that is, inactivated vaccines can only be'mixed' with inactivated vaccines. Different types of vaccines Vaccines, such as inactivated vaccines, adenovirus vector vaccines, and recombinant subunit vaccines cannot be replaced." (End)