The first of many freezer-packed COVID-19 vaccine vials have made their way to distribution sites across the US, as the nation’s pandemic deaths approached the horrifying milestone of 300,000.

The rollout of the Pfizer vaccine, the first to be approved by the Food and Drug Administration, ushers in the biggest vaccination effort in US history – one that health officials hope the American public will embrace, even as some have voiced initial scepticism or worry.

The first of the vaccines are likely to be given this week. Senior US government officials, including some White House staff who work close to President Donald Trump and Vice-President Mike Pence, are reportedly first in line, according to The Associated Press.

The move is reportedly meant to prevent more COVID-19 spread in the White House, which has already suffered from several outbreaks of the virus. Mr Trump, first lady Melania Trump and their son Barron are among those had the virus, as well as a host of top officials.

“Senior officials across all three branches of government will receive vaccinations pursuant to continuity of government protocols established in executive policy,” National Security Council spokesperson John Ulyot told AP.

“The American people should have confidence that they are receiving the same safe and effective vaccine as senior officials of the United States government on the advice of public health professionals and national security leadership.”

Elsewhere, the early public distribution of the life-saving jab will be limited to front-line health workers and people in nursing homes and long-term care facilities.

On Sunday (local time), workers at Pfizer – dressed in fluorescent yellow clothing, hard hats and gloves – wasted no time as they packed vials into boxes.

The vaccines were then taken from Pfizer’s factory in Portage, Michigan, an airport at Grand Rapids. The first cargo plane took off amid what airport officials called a “jubilant” mood.

“This is a historic day,” said Richard Smith, who oversees operations in the Americas for FedEx Express. The company is delivering 630 packages of vaccine to distribution sites across the country.

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The United Parcel Service also is transporting a share of the vaccine.

Tracked with GPS-enabled sensors, the initial shipments were expected to contain about three million doses, with many more to come.

In California, where health care workers will be among the first to be vaccinated, state health officials are prioritising hospitals that have adequate storage capacity, serve high-risk populations and that have the ability to vaccinate people quickly.

The vaccine is being shipped from the Michigan plant to sites across the US Photo: Getty

A survey from The Associated Press-NORC Centre for Public Affairs Research found that about half of Americans want to get the vaccine as soon as possible. Another quarter were unsure, while the remaining quarter said they were not interested.

Some simply oppose vaccines in general. Others are concerned that the vaccines have been rushed and want to see how the rollout goes.

While the vaccine was determined to be safe, British regulators are investigating several severe allergic reactions.

The FDA’s instructions tell providers not to give it to those with known histories of severe allergic reactions to any of its ingredients.

The Moderna vaccine will be reviewed by an expert panel in the US next week. It could be permitted for public use soon afterwards.

-with AAP