Beginning Feb. 15, anyone coming to the United Kingdom from a country on its travel ban list of COVID-19 hotspots must quarantine in a government-approved hotel for 10 nights, the U.K. government announced Thursday.

Most foreign nationals from high-risk nations already face U.K. travel restrictions due to the coronavirus pandemic. But this new rule will apply to U.K. citizens and residents arriving from one of the 33 "red list" countries: Angola, Argentina, Bolivia, Botswana, Brazil, Burundi, Cape Verde, Chile, Colombia, Democratic Republic of the Congo, Ecuador, Eswatini, French Guiana, Guyana, Lesotho, Malawi, Mauritius, Mozambique, Namibia, Panama, Paraguay, Peru, Portugal (including Madeira and the Azores), Rwanda, Seychelles, South Africa, Suriname, Tanzania, United Arab Emirates, Uruguay, Venezuela, Zambia and Zimbabwe.

Security will escort guests to their quarantine rooms when they arrive and must accompany them if they wish to access outside space for fresh air or a smoke. Three meals per day and laundry service will also be provided during their stay.

Those in quarantine will be required to take a COVID-19 test on both Day 2 and Day 8.

ABC News’ Zoe Magee contributed to this report.

Denmark, the Netherlands and Norway have joined the growing list of European countries that have said they won't recommend older age groups receive the COVID-19 vaccine developed by England's University of Oxford and British-Swedish pharmaceutical giant AstraZeneca until more data from clinical trials becomes available.

The Danish Health Authority said Thursday that it will recommend the Oxford/AstraZeneca vaccine to people under the age of 65 who are not at risk of serious illness from COVID-19. The drugs regulator citied a lack of documentation as to the vaccine's efficacy in older age groups.

The Norwegian Institute of Public Health said it will also limit use of the Oxford/AstraZeneca vaccine to those under 65 because there had been few participants older than that in the trial conducted by AstraZeneca.

Meanwhile, the Dutch Health Council said the efficacy of the Oxford/AstraZeneca vaccine in those over 55 "cannot yet be calculated because they participated only to a limited extent in the vaccine studies."

Belgium, France and Germany have made similar moves recently, while Switzerland went a step further and declined to authorize the Oxford/AstraZeneca vaccine for any age group, citing insufficient data.

The number of COVID-19 vaccine doses delivered across the United States over the past week dropped 22.5%, but the amount of doses administered increased 13.5%, according to a report from the U.S. Department of Health and Human Services.

The country has also seen a three-week downward trend in new COVID-19 cases, resulting in a 44% decline in the seven-day daily average since the peak on Jan. 8, the report said.

Still, the current number of daily cases remains over twice as high as the numbers during prior peaks.

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

There are currently 91,000 people hospitalized with COVID-19 in the United States -- the lowest since Nov. 28, which was two days after Thanksgiving, according to an ABC News analysis of data compiled by The COVID Tracking Project, a volunteer-run effort to track the U.S. outbreak.

COVID-19 hospitalizations have declined across the country by nearly 30% over the last three weeks.

In the span of three weeks, the national seven-day average of daily COVID-19 cases has declined by 45.6% -- the steepest and most consistent non-holiday-related drop in cases the U.S. has seen since the summer.

ABC News’ Arielle Mitropoulos contributed to this report.

An accommodation facility for refugees in the German city of Cologne has been hit by new, more contagious variants of the novel coronavirus, city officials said.

At least 41 residents of the Herkulesstrasse facility have tested positive for COVID-19. Variants first identified in South Africa or Brazil have been detected in 31 of them so far, according to a statement from the city government on Sunday.

At least 16 staff members at the facility have also tested positive for COVID-19, with the South Africa variant detected in 11 of them so far. Variant analysis is still pending on the other five, according to the statement.

All residents of the facility have been under quarantine since Friday, while the site has been under surveillance since Sunday. Entry into the refugee accommodation center, which can house up to 600 people, is currently banned, according to the statement.

The first known COVID-19 cases were confirmed among two employees at the facility about 10 days ago, while the first case of a variant was confirmed last week, according to the statement.

Dr. Harald Rau, head of Cologne's public health department, said the detection of variants at the refugee accommodation center "is a clear alarm signal for all of us."

"I ask all people in Cologne to avoid contact even more consistently than before and to follow the distance and hygiene rules of infection protection," Rau said in a statement Sunday.