(Photo : Getty Images: Mark Makela / Stringer)

President Biden's vaccine effort is one of his first orders as the U.S. rejoined the World Health Organization. 

President Joe Biden revised a crucial foreign policy decision made last year by his predecessor, Donald Trump, after accusing the U.N. health agency of corruption and bowing to Chinese pressure over the coronavirus pandemic.

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Trump decided to stop the funding to the WHO in April last year, as the coronavirus pandemic spread worldwide, claiming it was " virtually controlled by China" He then went on, triggering the mechanism to pull the U.S. out of the company entirely.

The withdrawal was due to go into effect in July of this year, but the Biden order will cancel it.

As the U.S. death toll from COVID approached 400,000, more significant than any other country, Biden reversed Trump's decision to leave the WHO on his first day in office.

U.S. has been the largest donor to WHO, making obligatory and voluntary donations of $400 million to $500 million. Trump's decision last year attracted sharp criticism in Congress and allies in Europe. In the fight against coronavirus, the WHO has been heavily involved, especially in developing countries.

The incoming administration is preparing to attend this week's WHO Executive Board meeting, with Fauci, the top U.S. expert on infectious diseases, leading the delegation and speaking. Once the U.S. resumes its interaction with the WHO, according to a fact sheet released by the Biden transition team, the new administration will work with the body to improve and reform the group.

In the meantime, the president said that to help curb the spread of the surging coronavirus. Biden would sign executive orders requiring masks and physical distance in all federal buildings - including government office buildings and federal lands and by federal workers and contractors. He said that this would be part of a "100-day masking challenge" to get Americans to wear masks openly.

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Earlier this week, Antony Blinken, Biden's preference for Secretary of State, said that a U.S. split with WHO could be healing and that the U.S. was planning to join Covax, the WHO-led initiative, the Vaccine Alliance's Coalition for Disease Preparedness Technologies, and Gavi.

At Thursday's session, Fauci, director of the National Institute of Allergy and Infectious Diseases, spoke of a series of executive board meetings that started Monday. On Twitter late Wednesday, WHO Director-General Tedros Adhanom Ghebreyesus congratulated Biden and Vice President Kamala Harris.

COVAX has announced that it has obtained access to nearly 2 billion doses, with deliveries due to start in the first quarter, and has set a target of vaccinating up to one-fifth of the country's population by the end of the year as a vaccine effort. Fauci said the U.S. looks forward to reform and enhance the organization with other WHO member countries.

As U.S. deaths topped 400,000 in the world's worst Covid-19 death toll on Tuesday. The 92-nation alliance aiming to deploy the Covid-19 vaccine effort to nations across the globe will be more effective. While the Trump administration, through Operation Warp Pace, has given some $18 billion to vaccine effort and drug production, it declined to participate in COVAX.

U.S. involvement would help shore up the vaccine-equity program. China is one of the partner nations. While its vaccine effort is not among those procured by Covax, Sinovac Biotech Ltd., a Chinese drugmaker, said it had submitted pre-qualification data on its shot. The E.U is also funding the proposal.

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