Hundreds of thousands of people in China have been given a Covid-19 vaccine which has been approved for emergency use.
The Chinese vaccines have been administered before final regulatory approval for general use.
It is an unusual move that raises ethical and safety questions, as companies and governments worldwide race to develop a vaccine that will stop the spread of the coronavirus.
A popular writer and columnist who has been given the vaccine said he had no reaction after the first dose. But after the second dose, Kan Chai felt woozy, saying: “When I was driving on the road, I suddenly felt a bit dizzy, as if I was driving drunk.
“So I specially found a place to stop the car, rest a bit and then I felt better.”
Chinese companies earlier drew attention after giving the vaccine to their top executives and leading researchers before human trials to test their safety and efficacy had even begun.
In recent months, they have injected a far larger number under an emergency use designation approved in June, and that number appears poised to rise.
A health official said that China, which claims to have largely controlled the disease, needs to take steps to prevent it from coming back.
One outside expert has questioned the need for emergency use when the virus is no longer spreading in the country where it was first detected.
It is unclear exactly who and how many people have been injected so far, but Chinese vaccine makers have offered some clues.
The state-owned Sinopharm subsidiary CNBG has given the vaccine to 350,000 people outside its clinical trials, which have about 40,000 people enrolled, a top CNBG executive said recently.
Another company, SinoVac, has injected 90% of its employees and family members, or about 3,000 people, mostly under the emergency-use provision, CEO Yin Weidong said.
It has also provided tens of thousands of rounds of its CoronaVac for the Beijing city government.
Another candidate being jointly developed by the military and CanSino, a biopharmaceutical company, has been approved for emergency use in military personnel.
Now, large Chinese firms including telecom giant Huawei and broadcaster Phoenix TV has announced they are working with Sinopharm to get the vaccine for their employees.
Several people who say they work in “front-line” organizations have said on social media that their workplaces have offered vaccinations for about 1,000 yuan (£117).
In an established but limited practice, experimental medications have been approved historically for use when they are still in the third and last phase of human trials. Chinese companies have four vaccines in phase three – two from Sinopharm and one each from SinoVac and CanSino.
National health commission official Zheng Zhongwei said at a news conference that the Chinese government referenced the World Health Organisation’s emergency-use principles to create its own through a strict process.
Mr Zheng said there have been no serious side effects in the clinical trials.
Under the emergency rule, high-risk personnel such as medical and customs workers and those who have to work overseas are given priority access, he said. He declined to provide exact numbers.
“In China’s case, the pressure in preventing imported infections and domestic resurgence is still huge,” Zheng added.
However, Diego Silva, a lecturer in Bioethics at the University of Sydney, said that giving vaccines to hundreds of thousands outside of clinical trials does not have “scientific merit” in China, where there are currently very few locally transmitted cases, and incoming arrivals are quarantined centrally.
“If it’s in the US where the virus is still raging that’s a bit different, but in a country like China it doesn’t seem to make sense to me,” he said.
“Because there’s not enough of the virus in China locally to deduce anything, you’re introducing a whole host of others factors”, by injecting people outside of trials.
Mr Zheng said that all those injected under emergency use are being closely tracked for any adverse health effects.