The United Kingdom announced Thursday new travel restrictions for six countries over concerns about a new variant of the novel coronavirus that emerged in South Africa.

The variant, known as B.1.1.529, has also been found in Botswana and Hong Kong in travelers from southern Africa. It has not yet been detected in the U.K., officials said.

"The early indications we have of this variant is that it may be more transmissible than the delta variant, and the vaccines that we currently have may be less effective against it," U.K. Health Secretary Sajid Javid said during a briefing Thursday.

Starting midday on Friday, all flights from six southern African countries -- South Africa, Namibia, Lesotho, Eswatini, Zimbabwe and Botswana -- will be temporarily suspended, and travelers entering the U.K. from those countries after 4 a.m. on Sunday must quarantine in a government-approved hotel for 10 days.

Currently, B.1.1.529 is not designated by the World Health Organization as a variant "of concern" or "of interest." So far, 22 cases have been confirmed in South Africa, according to the country's National Institute for Communicable Diseases.

The WHO's technical working group is scheduled to meet Friday to assess the new variant and may decide whether to give it a name from the Greek alphabet, based on its naming system for variants of concern and variants of interest.

The virus evolves as it spreads and many new variants, including those with worrying mutations, often just die out. Scientists monitor for possible changes that could be more transmissible or deadly, but sorting out whether new variants will have a public health impact can take time.

-ABC News' Rashid Haddou-Riffi

Czech President Miloš Zeman was taken to the hospital after testing positive for COVID-19 Thursday, his office said.

The 77-year-old leader had recently left the hospital for an unrelated chronic condition, Reuters reported.

The update came hours after the Czech government issued a 10 p.m. curfew for bars and clubs and banned Christmas markets amid one of the highest rates COVID-19 transmission globally, according to Reuters.

The new restrictions fall short of lockdowns issued in neighboring Slovakia and Austria, which have even higher rates of infection.

The Copper Queen Community Hospital in Bisbee, Arizona, is "operating in crisis care" due to the latest surge of COVID-19 cases in the state, local ABC affiliate KNXV reported.

The hospital only had 13 beds available and was "really struggling," according to the Arizona Department of Health Services.

The state reported its 84,813th COVID-19 hospitalization on Tuesday, according to health department data. Arizona reported more than 4,000 new COVID-19 cases on Wednesday.

Germany has become the latest country to surpass 100,000 deaths from COVID-19 since the pandemic began, according to official figures released Thursday.

The Western European country recorded 351 fatalities from the disease in the past 24 hours, bringing the death toll to 100,119, according to data from the Robert Koch Institute, Germany's public health agency.

In Europe, Germany is the fifth country to reach that grim milestone, after Russia, the United Kingdom, Italy and France.

Germany, the largest economy in Europe, is among several countries on the continent that are grappling with a recent resurgence in COVID-19 cases. Last week, the German government imposed tougher restrictions to curb the new wave of infections, as hospital beds quickly fill up.

German Health Minister Jens Spahn warned citizens that their survival could hinge on their vaccination status.

"Some would say this is cynical but probably by the end of this winter, pretty much everyone in Germany will be vaccinated, recovered or dead," Spahn told reporters in Berlin on Monday. "That’s the reality."