BEIJING (NYTIMES) - China wants to beat the world in the race to find a coronavirus vaccine - and, by some measures, it is doing just that.

Desperate to protect its people and to deflect growing international criticism of how it handled the outbreak, it has slashed red tape and offered resources to drug companies. Four Chinese companies have started testing their vaccine candidates on humans, more than the United States and Britain combined.

But China's leaders have empowered a vaccine industry that has long been mired in quality problems and scandals. Just two years ago, Chinese parents erupted in fury after they discovered ineffective vaccines had been given mostly to babies.

Finding a vaccine isn't enough. China's companies must also win over the trust of the public, who might be more inclined to choose a foreign-made vaccine over a Chinese one.

"The Chinese now do not have confidence in the vaccines produced in China," said Ray Yip, former head of the Gates Foundation in China.

"That's probably going to be the biggest headache. If they didn't have all those incidents, people will probably line up by the miles to get it."

The need is urgent. More than 247,000 people have died globally, by official figures as of Monday, and the true count is probably much higher. The coronavirus remains stubbornly difficult to stamp out. Even China, which officially appears to have tamed the spread, has suffered from sporadic outbreaks.

China also wants to deflect accusations that its silencing of early warnings contributed to the global pandemic. Developing a vaccine for the world would, in addition, burnish its standing as a global scientific and medical power.

So China has made its vaccine a national priority, although it has not disclosed spending details. One senior official said a vaccine for emergency use could be ready by September. State media has made a celebrity out of Chen Wei, the Chinese military's top virologist, who is leading one of the vaccine efforts. The public is responding.

Huang Shiyue, an 18-year-old first-year medical student in Wuhan, left her apartment on a recent early Sunday for the first time in three months to take a taxi to a wellness centre an hour away. There, she offered up her arm in the name of science.

But in an illustration of how difficult it will be to find a safe and effective treatment, Huang grew dizzy and sick.

"If I can help and benefit people with one little move," she said, "then I think this is a very worthwhile thing."

The vaccine that Huang received is being developed by CanSino Biologics, a Tianjin-based pharmaceutical firm, and the medical science arm of the People's Liberation Army.

The CanSino vaccine was the first to enter phase two trials, which in the hierarchy of drug testing means it is further along than the world's other candidates, although there is no guarantee that it will be proven effective. (It has been tested so far on 508 people; a candidate from Oxford University in phase one trials, or earlier-stage testing, has been administered to twice as many people.)

One other Chinese institution also has a candidate in phase two testing - the Wuhan Institute of Biological Products, an arm of state-run Sinopharm Group. Sinovac Biotech, a private company, and the Beijing Institute of Biological Products, which also belongs to Sinopharm, have potential vaccines in phase one trials.

The Wuhan institute was involved in a 2018 scandal in which defective vaccines for diphtheria, tetanus, whooping cough and other conditions were injected into hundreds of thousands of babies. China imposed a US$1.3 billion (S$1.84 billion) fine on another virus-maker involved, Changchun Changsheng. The scandal led to the firing of dozens of officials and pledges of a swift industry cleanup.

The government confiscated the Wuhan institute's "illegal income," fined the company and punished nine executives.

The Wuhan institute has been sued at least twice in China by plaintiffs who have alleged that the institute's vaccines have caused "abnormal reactions," according to court documents. In both cases, the court ruled that the Wuhan institute had to partially compensate the victims a total of roughly US$71,500. Its executives have been accused at least three times of bribing officials at local centre for disease control in various provinces to thank them for purchasing their vaccines. The executives were convicted, but no criminal charges were pursued against the company.

Sinovac Biotech had also been involved in a bribery scandal, according to court documents. From 2002 to 2014, a court in Beijing said, the general manager of Sinovac Biotech gave China's deputy director in charge of drug evaluations nearly US$50,000 to help the firm with drug approvals. Sinovac was not charged. The general manager was a man surnamed Yin, the documents showed. Chinese media reports have said that person is the current chief executive, Yin Weidong, who held the title of general manager from 2001 to 2017.

Sinovac, the Wuhan institute, and its parent, China National Biotec Group, did not respond to requests for comment.

Despite the companies' earlier stumbles, the Chinese government has given them permission to accelerate trials. Regulators in the United States and other places have done the same for other companies.

The Wuhan institute, Sinovac and the Beijing institute got combined approvals to run the first two phases, a decision questioned by several Chinese scientists, who felt that safety results from the first phase should be evaluated before the second phase was begun.