Don't worry too much about the new crown vaccine

Reporter Zhang Lei

What is the status of the new coronavirus mutant strain that appeared in India? Does the flocculent substance found in the vial during vaccination affect the effectiveness of vaccination? Can two doses of inactivated vaccine be given by different manufacturers? The joint prevention and control mechanism of the State Council held a press conference in Beijing on May 20, and relevant experts from the China Center for Disease Control and Prevention and the vaccine R&D task force answered media questions on the above-mentioned hot issues.

China's vaccine can cope with mutated strains

Wu Zunyou, chief epidemiologist of the Chinese CDC, said that the World Health Organization has a global monitoring network for new coronavirus mutations, and each country has to report to this network the newly emerged mutated strains in their countries. On this surveillance network, it can be seen that more than 3,000 mutated strains have been reported in India. The actual number of mutated strains is much higher than that, as the monitored cases represent only a small fraction of the total number of cases.

"It's not the more mutated strains that are scary, it depends on the nature of the virus mutation." Wu Zunyou said that the WHO divided the virus variation into three categories: the first category is particularly "need to be vigilant variant strains", such as the United Kingdom, Brazil appeared variant strains; the second category is "worthy of attention variant strains", India's variant strains belong to this category; the third category is The third category is "mutated strains that do not require attention", where minor mutations do not require attention.

So, can the new domestic vaccine cope with the mutated strains in India? Shao Yiming, a researcher at the CDC, said research is being conducted on the newly emerged mutant strain of Neocrown in India. "At the moment, there are two points that need to be informed to the public." One is that relevant companies and research institutions in China are closely tracking the virus mutations and conducting targeted research work, Shao Yiming said. Preliminary results show that our vaccine is still able to cope with the new coronavirus mutant strain that has emerged in India. Second, if a mutated strain of the virus does appear that the vaccine cannot cope with, our inactivated vaccine does not need to change the production process, but only needs to change the original vaccine strain to the new mutated strain at the feeding end of production, and then a new vaccine can be produced against the mutated strain. Therefore, the public can rest assured that our vaccine is fully capable of meeting the challenge of the new coronavirus variant.

Batch-by-batch inspection before release to market

Recently, some members of the public reflected that they found that a bottle of vaccine was given to two people when they were vaccinated, and they were worried that the insufficient amount would affect the vaccination effect. In this regard, Shao Yiming explained that the domestic two-dose New Crown vaccine and the one-dose New Crown vaccine are the same in terms of raw and auxiliary materials, production formula, packaging materials and process parameters, and the difference lies in whether the dosage is one or two doses. "In order to ensure that each person is injected in sufficient quantity, the amount of each bottle is sufficient, so the public need not worry about the problem of insufficient dosage. Internationally, vaccines from many countries, including those exported from our country, are multi-dose, such as 5 doses and 10 doses are available. The advantage of it is that more vaccines can be transported in the same time, saving the transportation capacity of packages and transportation for mass vaccination." Shao Yiming said.

Other members of the public have expressed concern about the quality of the vaccine after finding flocculent material in the bottles when they were vaccinated with the new crown vaccine. In this regard, Shao Yiming explained that the new crown vaccine produced by each manufacturer in China is subject to self-inspection by the manufacturer in accordance with national standards, and is also submitted to the drug inspection agency for batch-by-batch inspection before being released to the market. Each finished product of the new crown vaccine is subject to a strict permeation inspection process, and products that fail the permeation inspection are directly rejected. Therefore, the vaccine we observe is often not clear and transparent. Since the NIC vaccine contains aluminum adjuvant, it may settle before use, but it should be able to be shaken and dispersed.

In addition, some members of the public found that two doses of the vaccine were produced by different manufacturers, for example, the first dose was produced by Beijing Bio and the second dose was produced by Beijing Kexing, and they were worried that the "mixed" vaccination would affect the effectiveness of the vaccination. In this regard, Wang Huaqing, chief expert of immunization planning of the Chinese CDC, said that there are three technical routes of inactivated vaccine, adenovirus vector vaccine and protein subunit vaccine for domestic conditional listing of neo-coronavirus vaccine, and as long as the vaccine is of the same technical route, the products of different manufacturers will not affect the vaccination effect. "The Technical Guideline for New Coronavirus Vaccination has made it clear that at this stage it is recommended to complete vaccination with the same vaccine product. In the case of special circumstances such as the vaccine cannot continue to be supplied or the vaccine recipient is vaccinated in a different place and cannot complete vaccination with the same vaccine product, vaccination can be completed with vaccine products from other manufacturers of the same type." Wang Huaqing said that for vaccines that require two or more doses to complete the entire immunization process, if the prescribed interval is exceeded, there is generally no need to restart the subsequent vaccination. For example, if a second dose of inactivated vaccine has not been given at an interval of more than eight weeks, there is no need to revaccinate and a second dose can be given as soon as possible.