US President-elect Joe Biden to announce vaccines plan

US President-elect Joe Biden was set to announce his Covid-19 vaccine rollout plan Friday as he bids to wrest the focus from the impeachment of Donald Trump to the agenda for his first days in office.

Biden has said he wants 100 million Americans to receive shots during his first 100 days in office, an ambitious goal that would require a big step up in the current pace of distribution.

"The vaccines offer so much hope," the 78-year-old Democrat said Thursday night as he unveiled a $1.9 trillion stimulus package for the battered economy.

"But the vaccine rollout in the United States has been a dismal failure thus far," he added.

As of Thursday morning, some 30 million doses had been sent to states and 11.1 million had been injected into arms, according to official data, well behind the Trump administration's target of 20 million in December.

Biden's afternoon address from his home in Wilmington comes amid the impending Senate trial of Trump for inciting insurrection during the violent riot at the US Capitol on January 6.

That introduces political drama and scheduling complications as the incoming leader gets to work.

More than 388,000 people have lost their lives to the virus, a figure that is likely to have crossed 400,000 by the time Biden is sworn into office on January 20.

The proposed stimulus package sets aside $20 billion for vaccine distribution and $50 billion for testing.

"We understand the gravity of the situation," Dr Celine Gounder, an infectious disease expert and member of Biden's coronavirus task force said Thursday during a livestream hosted by Johns Hopkins University.

"We are dealing with about 4,000 Americans dying from coronavirus every day. That is more than (the number who) died on 9/11, every day."

Experts credit the Trump administration's Operation Warp Speed (OWS) with helping to develop Covid-19 vaccines in record-breaking time, but say there was not enough planning for the "last mile," and distribution has been off to a rocky start.

Major differences have arisen in the rate at which states are administering their doses, and some states were criticized for being overly-prescriptive in their initial rollout, which slowed things down and even led to some shots expiring.

Gounder hinted at possible changes to come.

"The vaccine recommendations have just been very hard to operationalize on the ground," she said.

"And so we essentially need to make things simpler, whether that is simplifying the supply chain as I noted or simplifying the tiers of who is eligible for vaccination."

Biden is also making personnel changes, bringing in former Food and Drug Administration chief Dr David Kessler to lead OWS and replace scientist and former pharmaceutical executive Dr Moncef Slaoui.

The Trump administration has already moved to release second doses of the Pfizer and Moderna vaccines that were being held back in reserve, and is recommending to states to begin vaccinating everyone over the age of 65.

While distribution by states was the main bottleneck in the first few weeks of rollout, the supply of doses itself is becoming an issue.

New York Mayor Bill de Blasio on Wednesday said the city would miss its inoculation goals if it didn't receive more vaccines soon.