WASHINGTON: The United States demanded a "robust and clear" international probe into the origins of the coronavirus pandemic, as a team of World Health Organization experts in China waited on Thursday for approval to begin its long-awaited Covid-19 probe.
The call came as coronavirus infections shot past 100 million and governments scrambled to get their hands on scarce vaccine doses, with a bitter row erupting between the European Union and Britain over the supply of AstraZeneca shots.
Beijing has so far frustrated international efforts to track the origins of the virus, which has killed more than 2.1 million people globally, and only recently allowed the WHO team into China after repeated delays.
"It's imperative that we get to the bottom of the early days of the pandemic in China, and we've been supportive of an international investigation that we feel should be robust and clear," White House spokeswoman Jen Psaki said on Wednesday.
President Joe Biden's predecessor Donald Trump had enraged China by accusing it of a botched response to the initial outbreak in Wuhan, and had led calls for an independent investigation.
China has sought to deflect blame for the massive global human and economic toll by suggesting -- without proof -- that the virus emerged somewhere else.
The highly anticipated WHO mission was expected to begin its work under tight security on Thursday as team members finished their 14-day quarantine after arriving in China.
But relatives of those who died in Wuhan have accused Chinese authorities of deleting their social media group and putting pressure on them to keep quiet, apparently to avoid any embarrassment during the WHO probe.
- EU-Britain vaccine row -
The pandemic has surged despite many nations kicking off mass vaccination programs, and one major issue in recent weeks has been of demand for jabs far outstripping supply.
With cases surging across Europe, the EU has demanded that AstraZeneca make up for delays by supplying doses from its factories in the UK.
But Britain has told the firm to honor its delivery promises too as it tries to accelerate its program, even using historic sites such as the Salisbury Cathedral and Lord's cricket ground as vaccination centers.
AstraZeneca has said there is simply not enough to go around.
At least 90 million doses of that vaccine, which AstraZeneca developed with the University of Oxford, will be produced in Japan, government spokesman Katsunobu Kato said on Thursday, but local media said they may not be distributed until May.
Pfizer, which developed its successful vaccine with BioNTech, has revised higher its production target for this year from 1.3 billion doses to 2 billion.
While part of that is down to increased production, it is also impacted by a change in how the firm counts doses -- after initially saying each vial contained five, the pharma giant now says six shots can be extracted.
- Olympics doubts -
Vaccines are considered critical to eventually defeating Covid-19, which has continued to re-emerge even in nations where it was brought under control.
New Zealand confirmed two new cases of the more virulent South African coronavirus strain on Thursday, days after an initial case that ended a run of more than two months without any community transmission.
The Pacific nation topped a list published Thursday by the Lowy Institute, a top Australian think tank, assessing almost 100 countries on how they managed the pandemic.
Brazil was ranked the worst, at number 98, with Mexico, Colombia, Iran and the United States also near the bottom.
Vietnam, which made the top 10, on Thursday reported its first community transmission in nearly two months.
The lack of success globally in containing the pandemic sparked doubts about whether the delayed Tokyo Olympics can be held at all this year.
But the head of the International Olympic Committee insisted organizers were focused on how -- not if -- the Games will be held.
"Our task is to organize Olympic Games, not to cancel Olympic Games," said Thomas Bach.
"And that is why we will not add fuel to this speculation."