(Bloomberg) -- President Joseph Biden’s team is increasingly worried the coronavirus pandemic is spiraling out of control -- imperiling his promise to contain the outbreak -- as cases and deaths mount, vaccinations lag and a more transmissible strain of the virus emerges in the U.S., according to people familiar with the matter.

As they learned more about the federal response to the pandemic, Biden’s transition team grew alarmed at a lack of coordination with states, the people said. Biden himself has warned of a “dark winter” and has flatly said the pandemic will worsen before it improves.

The stakes are escalating. U.S. hospitalizations are at near-record levels, and daily cases and deaths have doubled since Election Day. While blame has fallen on the Trump administration for its failure to develop a national testing or vaccination strategy or encourage widespread mask-wearing, Biden’s team -- which keeps adding new experts -- now inherits the job of containing the pandemic.

On Thursday, Biden will sign executive actions to “move aggressively to change the course of the COVID-19 crisis and safely re-open schools and businesses, including by taking action to mitigate spread through expanding testing, protecting workers, and establishing clear public health standards,” according to a memo by Ron Klain, the White House chief of staff. After taking office on Wednesday, one of Biden’s first acts was expected to be an order requiring face masks on federal property.

The most alarming developments have come over the past month. Some Biden advisers, who asked not to be identified discussing internal conversations, said it isn’t vaccine logistics that worry them most, but the new strain of the virus, which is more contagious. The U.S. already has a perilously high baseline caseload -- about 230,000 new infections a day, of late -- that could quickly become unmanageable as the mutant strain takes hold.

“This administration is inheriting such a horrible problem, not of their making,” said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota and a member of the coronavirus advisory board for Biden’s transition. “This is a perfect storm.”

Biden has staked much of his early presidency on achievements in his first 100 days, including a pledge to administer 100 million doses of vaccine and a challenge to Americans to routinely wear masks. His team hopes to vastly increase testing and push to reopen schools, trying to both do more to fight the virus and return Americans to a more normal daily life.

But the risk of explosive new strains, including a U.K. variant known as B.1.1.7, threatens to upend it all and leave Biden at the end of his first 100 days with a pandemic that has worsened, instead of improved. There’s concern among his team that the scope of the problem he’s inherited is far worse than anticipated, posing a political risk to Biden’s White House.

If the new president fails to combat the virus effectively in its first few months, efforts to revive the economy or achieve other legislative priorities including an immigration overhaul or infrastructure development could be hamstrung.

Biden’s aides privately allege that Trump’s administration dragged its heels in showing them details of the federal response and its data. Those concerns weren’t made public before the inauguration because Biden’s team believed it had to avoid publicly criticizing Trump’s team during the transition or risk being fully frozen out, people familiar with the matter said.

The first days of the administration will be spent getting up to speed on the state of the response, one person said.

A senior Trump administration official disputed that any information had been withheld from Biden’s transition, saying that since Thanksgiving, there had been more than 300 meetings with Biden officials across the Department of Health and Human Services. The Trump administration also provided Biden’s team what the official said was unprecedented access to several “deliberative meetings,” as well as debriefings for some of them.

The Trump official called it smart politics for Biden’s team to blame the outgoing administration for the issues it confronts and to lower expectations for its own performance, but said their assertions were neither accurate nor fair. The official asked not to be identified discussing a dispute with the incoming administration.

500,000 Cases Daily

On election day, the U.S. had never had a day with more than 100,000 new cases; since Nov. 5, it has never had a day with fewer than that. Osterholm predicted that the U.S. could see 400,000 to 500,000 daily new cases in 12 to 14 weeks, or roughly 100 days -- five times higher than on election day.

“When this B.1.1.7 takes off, it’s going to be hell,” Osterholm said. “That’s what they’re walking into right now. I hope I’m wrong. God, I hope I’m wrong.”

In their planning, Biden advisers are also factoring in an exhausted, demoralized and bare-bones workforce in its departmental agencies, particularly at the Centers for Disease Control and Prevention.

“Biden is coming in with entire offices gutted, or morale is so low,” said Kavita Patel, a nonresident fellow at the Brookings Institution, who served as director of policy for the Office of Intergovernmental Affairs and Public Engagement in Barack Obama’s administration.

A request for comment sent to the CDC before noon Wednesday, when Biden’s administration assumed power, was not immediately returned.

One Biden adviser laid out the uncertainties facing Biden’s coronavirus response. All of them carry only downside risk, the adviser said, in that they can only surprise by being worse, not better.

Vaccine distribution is anemic and faces supply constraints, the person said. The Trump administration official disputed this, saying that internal government projections showed the two manufacturers with currently licensed shots, Pfizer Inc. and Moderna Inc., on track to deliver 100 million doses each by the end of the first quarter.

But vaccinations have fallen far short of targets set by President Donald Trump, who promised in September to have 100 million shots available by the end of the year. Just 16 million doses had been administered as of Wednesday, according to the Bloomberg vaccine tracker.

Changing Cast

The rising urgency is reflected in Biden’s own approach -- during the transition he named a coronavirus advisory board, then a health team, and then a new batch of aides to bolster his response to the pandemic. Key positions remain unfilled, chiefly Food and Drug Administration commissioner.

“It’s going to take some time,” White House Press Secretary Jen Psaki told CNN Wednesday morning. “Our team is eager to get into agencies, into the White House to really gain a better assessment of how bad things are but we’re also going to be honest about what we’re looking at here.”

The team has retooled as the transition continued, shifting from a focus on testing early in the fall to a dual focus on both testing and vaccines as the pandemic shifted, one of the people said.

Another milestone came last week, with the Trump administration’s announcement that it would send out a reserve of doses held back to ensure supply of booster shots. But states later raised alarm, saying they expected a spike in shipments but didn’t receive any. Whatever stockpile was ever there is smaller than expected.

“Their biggest problem is that they do not know what land-mines or black holes they are walking into,” Patel said. “Nobody at HHS or Operation Warp Speed told them that they do not have any reserves of the vaccine.”

Biden’s advisers have debated -- a healthy disagreement, one said -- whether to signal the alarm more publicly, but some have argued that panic won’t help. Biden, for instance, didn’t issue sharp warnings about Thanksgiving and Christmas gatherings, which accelerated the pandemic.

Biden’s goal of 100 million doses looks uncertain. Trump aides have accused Biden of purposely setting a low bar for his vaccination target, to engineer a more easily achieved goal. But Biden’s team has privately wondered if it’s practical given manufacturing constraints at Pfizer and Moderna.

“It’s aspirational but I think it’s doable,” Osterholm said.

Biden’s team takes some solace. The vaccines work, though new strains threaten to degrade their efficacy. And one adviser wondered whether Biden’s public emphasis on mask-wearing and other sound public health practices would help, replacing Trump’s refusal to wear a mask and general scorn for recommended health guidelines.

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