August 27, Zheng Zhongwei, director of China’s Medical and Health Technology Development Research Center, said in response to reporters at a press conference that expert analysis believes that China’s current epidemic prevention and control situation is very good and designated medical institutions can carry out booster vaccination 6 months after immunization is completed.
He explained that during routine vaccination, it was found that people with relatively low immune function, and those over 60 , have less effects after vaccination than those aged 18-59 . The risk of severe, critical illness, and death after an infection , for this group , is higher than that of other populations. Therefore, experts suggest that for such people, a booster shot can be given 6 months after vaccination.
In addition, experts also advice that due to work, study, and travel needs, some people in China have to go to high-risk areas or abroad. This group can be given the booster shot after 6 months of vaccination .
However, at this stage, experts caution that further research is needed, and a comprehensive study and judgment should be made according to the situation of the epidemic , on whether to carry out booster immunization for the whole population 6 months after vaccination.
According to Zheng Zhongwei, recently China’s vaccine research and development team organized experts to conduct a special study on whether to carry out booster vaccination. The results found that the antibodies of the two vaccines , Sinopharm Zhongsheng and Beijing Kexing , used in the study , declined to varying degrees after 6 months of vaccination. In fact, the antibody declination after vaccination is the same as regular vaccines.
But after the decline, within 6 months, they had a third dose of vaccination. Firstly, they found that the vaccination was very safe, similar to the safety data of the first and second doses.
Secondly, after the third dose of vaccination, the recipient’s antibody level rose rapidly. It began to rise after 3 days, and rose to a higher level after 7 days. By 14 days, it was roughly equivalent to the original level. Range from 15-30 times. However, for those people who were vaccinated in less than 6 months , the antibodies still dropped , but the low point was higher than that of the 2 first doses . From this perspective, it was concluded that the protective effect of enhanced vaccination can be improved from the perspective of immunogenicity.