COVID-19 updates: US has 1st day since November with fewer than 100K new cases

Cases of the more contagious U.K. variant of the COVID-19 virus is spreading rapidly through the U.S., as much as doubling every 10 days, a new study suggests.

The study has not peer reviewed, so it has not been scrutinized for inaccuracies or context by specialists.

It is still not known whether the U.K. variant is more virulent or deadly, but it is more transmissible. The Centers for Disease Control and Prevention warned last month that the U.K. variant could become predominant in the U.S. by March if spread the way it did in the U.K.

Vaccines don’t seem to be strongly impacted by the U.K. variant, but scientists are concerned about the efficacy of the vaccines against the South African variant.

-ABC News’ Eric Strauss

A second storm bringing heavy snow to the Northeast has shut down vaccination sites in at least two states.

New York Gov. Andrew Cuomo and New Jersey Gov. Phil Murphy both announced that appointments for Sunday would be rescheduled due to the inclement weather.

Mass vaccination sites located indoors, such as the newly opened Yankee Stadium, will continue as scheduled as they have the infrastructure and equipment in place to ensure people can safely enter and exit the location, according to ABC New York station WABC.

Nine percent of Americans -- 28.9 million people – have received one or more vaccine doses, according to a report from the Department of Health and Human Services.

Two percent of Americans -- 7.5 million people -- have received two doses, the report said.

Deaths are down 4% since the peak on Jan. 13, while hospital admissions have decreased 37% since the Jan. 9 peak, the report said.

ABC News’ Josh Margolin and Brian Hartman contributed to this report.

New York state’s seven-day average positivity rate has fallen to 4.58% -- the lowest since Dec. 2, Gov. Andrew Cuomo announced Saturday.

New York has 7,804 COVID-19 patients in hospitals -- the lowest since Dec. 27, he added.

Cuomo called these numbers "a reflection of the discipline New Yorkers have shown to defeat the virus."

"Super Bowl weekend is here and while the instinct may be to celebrate together, we cannot get cocky -- we must continue doing the things we know are effective at taming the virus: wear a mask, adhere to social distancing, and avoid gatherings," he said.

ABC News’ Josh Hoyos contributed to this report.