3rd Sinovac Jab Reaps 'Remarkable' Antibody Results, Study Shows

By Alistair Baker-Brian, July 29, 2021

If you’ve already taken two doses of China’s Sinovac COVID-19 vaccine, you may be due a booster jab sometime in the future.

The results of a study published on medRxiv showed that a third dose of CoronaVac, administered six months or more after a second dose, resulted in a “remarkable increase in antibody levels.” The study has not been peer-reviewed as of press time.

The study also noted that optimizing the timing of a booster dose should take into account a variety of factors. These include immunogenicity, vaccine efficacy and effectiveness, local epidemic situation, infection risk and vaccine supply.

According to the World Health Organization (WHO), a large phase-three clinical trial in Brazil showed that, for those who took two doses, the Sinovac COVID-19 vaccine was 51% effective against symptomatic infection, 100% effective against severe COVID-19 and 100% effective against hospitalization.

An observational study on health workers in Manaus, Brazil suggested that, regarding protection against symptomatic infection, the vaccine had similar results against new variants of COVID-19. However, this information is being constantly updated given the constant emergence of new variants.

According to Our World in Data, China has administered 1.58 billion vaccine doses as of July 27, 2021. This includes both Sinovac and Sinopharm vaccines.

However, data is not available on how many of said doses constitute first and second doses, respectively. Therefore, it is not possible to know how many people in China are fully vaccinated.

Despite China’s large-scale vaccination program, an article in Wall Street Journal, published on June 22, suggested that China’s borders would not open for at least another year.

According to the article, the country remains wary of new variants and the subsequent potential disruption to key events, such as the Beijing 2022 Winter and Paralympic Olympics due to be held in February and March of next year.

[Cover image via Pixabay]