The U.K. reported 53,495 new cases on Thursday – the highest single-day rise since July 17, British health officials said.

Hospitalizations in the U.K. are down 6.5% over the last week while deaths are down 3% over the last week, officials said.

Over 80% of the 12-and-over population is fully vaccinated.

Thirty-two cases of the omicron variant have been detected in the U.K.

-ABC News' Christine Theodorou

As omicron appears to be rapidly overtaking delta as the dominant variant of the novel coronavirus in South Africa, a scientist warned Thursday that the new variant appears to be able to dodge some of the immunity from vaccines and previous infections.

Professor Anne von Gottberg, a clinical microbiologist at South Africa's National Institute for Communicable Diseases, told reporters during an online press briefing that omicron may not be more contagious or virulent than delta, but early data indicates previous infection does not provide protection against omicron as it seems to do with delta.

"We believe that omicron is widespread in the country," von Gottberg said.

South Africa and Botswana were the first countries to identify the omicron variant last month. Since then, South Africa has reported a total of 172 confirmed cases and Botswana has reported 19.

Over the past week, Southern Africa has recorded a spike in COVID-19 infections, hospitalizations and deaths, mostly driven by South Africa, where scientists believe omicron is rapidly becoming the dominant variant.

"It does look like there is a predominance of omicron throughout the country," von Gottberg said. "Almost 80% of specimens being sequenced in November are omicron. So we believe, truly, there is a link in the increase in cases with omicron variant."

The Minnesota Department of Health said a Minnesota resident with recent travel history to New York City has become the state's first confirmed case of the omicron variant.

The adult male lives in Hennepin County and has been vaccinated.

After experiencing mild symptoms on Nov. 22, he was tested on Nov. 24. He no longer has symptoms.

He attended an anime convention at the Javits Center in Manhattan from Nov. 19 to Nov. 21. Anime NYC said it welcomed 53,000 fans. New York Gov. Kathy Hochul said the state is in touch with health officials in Minnesota and she encouraged any of the 53,000 attendees to get tested.

New York City Mayor Bill de Blasio said, "we should assume there is community spread of the variant in our city."

“Since the beginning of this pandemic, Minnesota’s nation-leading genome sequencing infrastructure and strong testing network have allowed the state to quickly track the COVID-19 virus and better understand its spread. Today, those tools detected a case of the Omicron variant in Minnesota," Gov. Tim Walz said in a statement. "This news is concerning, but it is not a surprise. We know that this virus is highly infectious and moves quickly throughout the world."

Unvaccinated people in Germany will be barred from most businesses, except for grocery stores and pharmacies, officials announced Thursday.

In Germany, shops and restaurants check vaccination status at entrances.

Nearly 69% of Germans are fully vaccinated. The country has reported several cases of the omicron variant.

-ABC News'  Joe Simonetti

At least 10 people have tested positive for COVID-19 on a Cruise Norwegian ship disembarking in New Orleans this weekend, according to the Louisiana Department of Health.

Those infected include both passengers and crew members, officials said.

The Norwegian Breakaway departed from New Orleans on Nov. 28 and stopped in Belize, Honduras and Mexico on its voyage. There are more than 3,200 individuals on board, the health department said.

The company required on-site testing in addition to proof of vaccination before boarding the vessel, according to the Port of New Orleans.

The health department said the cruise line has been adhering to appropriate quarantine and isolation protocols. In addition, everyone aboard the ship will be tested for COVID prior to disembarking.

Those who test positive for COVID-19 on the ship will either travel by personal vehicle directly to their private residence or self-isolate according to current Centers fo Disease Control and Prevention guidelines in accommodations provided by Norwegian Cruise Lines.

"The health and safety of our guests, crew and the communities we visit is our highest priority, and we will continue to take all appropriate actions to ensure their wellbeing and protect public health," a Norwegian Cruise Lines spokesperson told ABC News.

"We have identified a handful of COVID-19 cases among guests and crew onboard Norwegian Breakaway, which is scheduled to disembark in New Orleans, LA on December 5. All of the identified cases onboard are asymptomatic. In addition to requiring that 100% of guests and crew are fully vaccinated, per the Company's comprehensive health and safety protocols, we have implemented quarantine, isolation and contact tracing procedures for identified cases."

The spokesperson said the company is testing all individuals prior to disembarkation, and providing post-exposure and quarantine public health guidance by the CDC.

"Any guests who have tested positive for COVID-19 will travel by personal vehicle to their personal residence or self-isolate in accommodations provided by the Company according to CDC guidelines," the spokesperson said. "We take this matter extremely seriously and will continue to work closely with the CDC, the office of Governor John Bel Edwards, the Louisiana Department of Health as well as the city and port of New Orleans. At this time, there have been no changes to scheduled future sailings on Norwegian Breakaway. We will provide additional updates to impacted guests as appropriate."