Recently, some media reported that WHO officials confirmed there emerged variations of the virus over time. What's the global COVID-19 variation situation currently? Will it affect the efficacy of vaccines? Thank you.
Thank you for your question. Virus variation may be an issue of great concern for the R&D of vaccines and disease prevention and control. In fact, virus is a simple agent, and virus mutation is a normal phenomenon. Generally speaking, the variation will not affect the severity or infectiousness of the disease, nor will it affect the immune response of the vaccine against the virus.
As a new coronavirus and an RNA virus, COVID-19 may mutate slightly faster than DNA viruses. Whether it's the WHO or the relevant institutions of countries, including vaccine R&D companies, they have been paying attention to the virus' variations and are conducting relevant studies. Existing studies have shown that the variation of the virus is within the normal range and it hasn't affected the effects of vaccines. I can introduce two relevant studies. We know that after the virus was isolated, several research institutions and disease prevention and control organizations sequenced its genome. At present, there are hundreds of thousands of shared viral genomes around the world. We have compared the COVID-19 genome with over a hundred thousand high-quality viral genomes and have yet to find a severe variation, and the existing variation is within the normal range. In addition, the relevant institutions in China have used the antibodies produced in the earlier stages of the vaccine R&D to neutralize strains from different sources, including those from overseas. According to those tests, the efficacy of the vaccine is still relatively good and has not changed.
All parties, including the WHO, the relevant institutions of various countries, and vaccine R&D companies will continue to study variations of the virus. Research data and analysis of variations will provide relevant evidence for future usage strategies of vaccines. In general, the mutation of the virus has yet to threaten the effectiveness of the vaccine.