Inactivated Vaccines Breached by Omicron... China's 'Vaccine Diplomacy' Loses Its Main Weapon [Reading Science]

[Image source=Yonhap News]

[Asia Economy Reporter Kim Bong-su] China’s self-developed vaccines, used to prevent the COVID-19 pandemic, have failed to provide protective effects against the Omicron variant. It is pointed out that China has lost its main weapon, which it had used to expand its influence through vaccine diplomacy targeting the Third World, where obtaining Western advanced vaccines was difficult.

According to the international academic journal Nature on the 15th, a study conducted in Hong Kong last December analyzed blood samples from 25 people who had received two doses of the inactivated Chinese COVID vaccine, and found that none of them had detectable antibodies against the Omicron variant. A research institute in Faridabad, India, also concluded that inactivated vaccines are not optimized for the Omicron variant.

Inactivated vaccines work by injecting molecules of the inactivated COVID-19 virus into the human body to induce antibody formation. They are stable and relatively easy to produce, so China’s state-owned vaccine companies produced them in large quantities for domestic epidemic control. Especially, these vaccines were mass-distributed to Third World countries such as South America and Africa, where expensive Western vaccines were hard to obtain, simultaneously strengthening China’s influence through so-called ‘vaccine diplomacy.’

[Image source=Yonhap News]

However, the situation changed with the emergence of the Omicron variant at the end of last year. Multiple studies have shown that inactivated vaccines have significantly lower protection against the Omicron variant compared to vaccines produced using messenger RNA (mRNA) or protein subunit methods. Representative inactivated vaccines include those made by China’s Sinovac and Sinopharm. According to the UK-based data company Airfinity in London, at least 11 billion doses of inactivated vaccines have been produced and administered worldwide. Of these, at least 5 to 11 billion doses of Chinese inactivated vaccines have been produced and administered globally, mainly in the Third World. Additionally, countries such as India, Iran, and Kazakhstan have also produced inactivated vaccines for domestic use.

However, there is research indicating that even inactivated vaccines provide some resistance to the Omicron variant when a third dose (booster shot) is administered. A study conducted by Shanghai Jiao Tong University School of Medicine on 292 people vaccinated with the inactivated vaccine BBIBP-CorV found that only 8 people retained neutralizing antibodies against Omicron 8 to 9 months after a single dose. However, after receiving a third dose, the number of people with Omicron antibodies increased to 228. A preprint paper published in December last year by researchers from Harvard and MIT also confirmed that individuals who received three doses of the COVID vaccine maintained antibodies capable of fighting the Omicron variant.

Experts advise that for people who have received two doses of inactivated vaccines, receiving a third dose of an mRNA or protein-based vaccine may be more effective against the Omicron variant.

Nature reported, “Some experiments have shown that receiving two doses of inactivated vaccine followed by an mRNA third dose maintains the quantity of antibodies and the memory of B cells and T cells in the natural immune system,” adding, “Research from China and the United Arab Emirates also indicates that protein-based booster shots generate more neutralizing antibodies than a third dose of inactivated vaccine.”