China has made a renewed push to promote the safety and effectiveness of its Covid-19 vaccines by pointing out that they were good enough for the country's entire leadership, including President Xi Jinping, to fully rely on them.

“All China’s incumbent party and state leaders have completed vaccination against the coronavirus with domestically developed vaccines,” Zeng Yixin, deputy director of the National Health Commission (NHC), told reporters on Saturday. He added that Chinese leaders have demonstrated a high level of trust in the Covid-19 inoculations developed by their own country.

The statement comes as China tries to crack down on flareups of the virus by imposing lockdowns or mass testing programs in such cities as Shanghai. More than 92% of China’s population has received at least one Covid-19 shot, while nearly 90% is considered fully vaccinated. Just under 71.7% have had a booster shot.

Like vaccines developed in other countries, the Chinese jabs haven’t fully halted the spread of the virus. However, the homegrown vaccines protect well against severe illness and death caused by Covid-19’s Omicron variants, said Feng Zijian, secretary general of the Chinese Preventive Medicine Association.

Research and development work is proceeding on new vaccines to deal with Omicron sub-variants, and some of those jabs are already undergoing clinical trials, Chinese officials added.

With China achieving high inoculation rates in its own population, the world’s largest, and providing billions of jabs to low- and middle-income countries, Beijing’s Sinopharm and CoronaVac have been among the most heavily used vaccines globally. China leads the world by far in doses administered domestically, at more than 3.4 billion, nearly six times the US total.