Medical staff and border inspection officials are among the key workers to have received the vaccine candidate, said the director of China’s National Health Commission Zheng Zhongwei.
He told state broadcaster CCTV it had been “in line with the law” to give high-risk workers jabs ever since the government approved the roll-out of “experimental use” vaccines on 22 July.
“Most cases in China now are imported, so border officials are a high-risk group,” said Mr Zheng – adding that those working in transport and at “wet markets” could be next in line for the vaccination programme.
The authorities could consider expanding the programme to try to prevent outbreaks during the autumn and winter, the official said.
Mr Zheng did not say which experimental vaccine had been used, or how many workers had been given jabs so far, according to a report in the South China Morning Post.
Four of the world’s seven vaccines that are in the third phase of trials are from China. Two of the candidates are from China National Biotec Group (CNBG), a unit of state-owned pharmaceutical giant China National Pharmaceutical Group.
Sinovac Biotech is developing the third candidate called CoronaVac, while CanSino Biologics is working with state military research unit Academy of Military Medical Sciences on Ad5-nCoV.
Before the official launch of the “emergency use” programme in July, China’s military approved the use of CanSino’s vaccine in June.
State media also reported in June that employees at state-owned firms travelling overseas were allowed to take one of two candidate vaccines.
Argentina, Peru, Morocco, Bahrain and the United Arab Emirates have allowed CNBG to run Phase 3 trials.
Indonesia and Brazil are helping with Phase 3 trials of Sinovac’s CoronaVac, while Bangladesh aims to run a late stage clinical trial for the experimental vaccine.
Pakistan, Saudi Arabia and Russia, meanwhile, have agreed to conduct Phase 3 trials of CanSino’s candidate, while Mexico has signed an early agreement with the Chinese firm for a late-stage trial.
Not all countries are comfortable with China’s vaccine experiments, however.
Papua New Guinea officials recently sent back a flight carrying 180 Chinese workers after a Chinese mining company in the country claimed to have given some employees an experimental Covid-19 vaccine.