Does COVID-19 vaccine need three shots now? What is the interval between COVID-19 vaccine and other vaccines

At present, China's COVID-19 vaccination work is ongoing, and some people have been vaccinated with COVID-19 vaccine. Generally, vaccinators need two injections, that is, the first injection and the second injection. But some people have heard that COVID-19 vaccine needs three injections. There must be a difference between two injections and three injections. So does COVID-19 vaccine need three injections? Let's learn about related issues together.

At present, COVID-19 inactivated vaccine is being inoculated, with a total of two doses, and the interval between the two doses is 14-28 days. The recommended immunization procedure of COVID-19 vaccine is 2 shots, with an interval of at least 14 days. The vaccination site is the deltoid muscle of the upper arm. In addition, because COVID-19 vaccine is a new vaccine, there is no safety and immunogenicity data for simultaneous vaccination with other vaccines, so it is not recommended to vaccinate with other vaccines at the same time. However, if there is a suspected rabies exposure who needs to be vaccinated with rabies vaccine and other trauma who need to be vaccinated with tetanus vaccine, priority should be given to vaccinate with rabies vaccine and tetanus vaccine. The interval between COVID-19 vaccine and other vaccines should not be less than 2 weeks.

Two doses: inactivated vaccine. Inactivated vaccines are vaccines prepared using a series of purification techniques after killing live viruses through physical and chemical methods. The main characteristics of this vaccine are that the vaccine ingredients are similar to natural viruses, the immune response is strong, and the safety is good. The vaccine is relatively stable and can be stored at 2-8 ℃ for 2-3 years. It is easy to transport. Two injections for immunization.

Three doses: recombinant protein vaccine. Recombinant protein vaccines are the most effective antigen components expressed in vitro cells through genetic engineering. Extracorporeal cells are engineered cell lines commonly used in biological products, similar to industrial fermentation, and ultimately produced into vaccines. The entire production process involves protein expression and purification, without the involvement of live viruses, making it safe and easy to produce on a large scale. From the past use process and experimental results of recombinant protein vaccines, the safety of recombinant protein vaccines can be guaranteed, and the adverse reaction rate is relatively low. Vaccines should be refrigerated at 2-8 ℃, with lower requirements for transportation and storage; 2-3 injections should be administered during vaccination.

At present, there is no evidence that different manufacturers or different types of new coronavirus vaccines can substitute for vaccination. At present, it is recommended to use the same vaccine from the same manufacturer for vaccination. It is not recommended to mix these two vaccines. People should use the same vaccine after the first and second injections. Vaccines from different manufacturers cannot be mixed, as even inactivated vaccines have different antigen content and adjuvant components. Mixing not only affects the efficacy, but may also increase the occurrence of adverse reactions and affect safety. Currently, various regions in China have begun to vaccinate key populations against COVID-19. If COVID-19 vaccine should not be mixed, can we get other types of vaccines (such as rabies vaccine) in the process of two doses of COVID-19 vaccine? Due to the lack of relevant research data on simultaneous vaccination of COVID-19 vaccine and other vaccines, COVID-19 vaccine and other vaccines should be vaccinated separately at an interval not less than two weeks before the national guidelines and programs are published.