Biden's former COVID-19 advisor says the variant found in the UK could become the dominant US strain and prompt a surge in cases and fresh lockdowns

• Michael Osterholm, an advisor to the Biden transition team, has a warning about a virus variant.
• On Sunday he said the variant could trigger a massive surge in US cases in within six to 14 weeks.
• If that happens, he said, "we are going to see something that we have not seen yet in this country."

Michael Osterholm, the infectious-disease expert who advised Joe Biden's presidential transition team on COVID-19, warned Sunday that the coronavirus variant first found in the UK could become the dominant strain in the US, causing an unprecedented wave of new cases.

"The surge that is likely to occur with this new variant from England is going to happen in the next six to 14 weeks," Osterholm said on NBC News on Sunday. He went on to say that if that happened, "we are going to see something that we have not seen yet in this country."

The variant is more contagious than the original strain of the novel virus. Recent studies, including from Pfizer and BioNTech, suggest existing vaccines should still work against it, though the companies have studied the variant only in laboratory conditions.

The Centers for Disease Control and Prevention on Monday said 467 cases of the variant had been identified in the US. Cases have been found in many US states, including New York, Florida, and California. Experts believe it was spreading in the US for several weeks before it was first identified.

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Osterholm, the director of the Center for Infectious Disease Research and Policy at the University of Minnesota, described the variant's immediate danger as an "ability to cause many more infections and much more serious illness."

UK Prime Minister Boris Johnson on January 22 announced preliminary evidence suggesting the variant could be deadlier than the original because infected people have higher viral loads. The UK government's chief scientific advisor, Patrick Vallance, estimated it could be as much as 30% more deadly, though he said more evidence was needed.

Some parts of the US have started relaxing COVID-19 restrictions as case counts fall: Illinois is allowing groups of 10 people to sit inside restaurants and bars, for example.

"We all want to end our pandemic fatigue and our pandemic anger - we got to turn that ship around too," Osterholm said.

He said Americans had to "understand that we're going to have to change quickly," adding, "As fast as we're opening restaurants, we're likely to be closing them in the near term."

Osterholm said "right now we're flying blind" in terms of identifying new coronavirus variants and urged people to "expect the unexpected in the days ahead."

On Sunday, Maryland officials confirmed the US's third case of the more-contagious coronavirus variant first found in South Africa. Maryland's governor said the man had not traveled abroad and most likely caught the variant in the community.

The US has reported more than 26.2 million coronavirus cases, and more than 441,000 Americans with COVID-19 have died, according The New York Times' coronavirus tracker.