A new variant of the novel coronavirus that was first identified in the United Kingdom has been detected in New York state, Gov. Andrew Cuomo announced Monday.

The patient is a man in Saratoga Country in his 60s, who had not traveled recently, suggesting community spread of variant. The patient was affiliated with a jewelry store, N. Fox Jewelers, where three other people have also tested positive for COVID-19, although it is not yet known if they have the same virus variant. Anyone who visited the store between Dec. 18 and 24 is being asked to contact the state and get a test immediately.

"From a public health point of view, it’s about contact tracing," Cuomo said. “We have to make sure we are doing everything we can do to effective contact tracing of this case."

Cases of the new variant have also been detected in Colorado, California and Florida.

-ABC News' Aaron Katersky contributed to this report.

British Prime Minister Boris Johnson announced Monday a strict nationwide lockdown for England, as a new variant of the novel coronavirus that was first identified in the United Kingdom continues to spread rapidly and rising COVID-19 infections strain the country's health care system.

Under the new restrictions, nonessential workers are only allowed to leave home for essential food and medicine or to exercise. Meanwhile, all schools and universities must shift to remote learning.

"We must go into a national lockdown that is tough enough to contain this variant," Johnson said Monday.

While nonessential shops and hair salons are ordered to close, supermarkets, garden centers and churches can stay open. Restaurants can continue offering takeout and delivery services, but customers aren't allowed to add alcohol to their orders.

The lockdown, which goes into effect immediately and is to be in place until mid-February, will be enforced by police.

The announcement comes as the U.K. saw a record 58,784 newly confirmed cases of COVID-19 on Sunday, along with an additional 407 deaths from the disease.

Prior to the nationwide lockdown being announced, England was under a set of tiered COVID-19 restrictions, with London in the highest level 4.

Although Johnson is the U.K. prime minister, his government is only responsible for lockdown restrictions in England because public health legislation is devolved to national governments within the U.K., meaning that Scotland, Wales and Northern Ireland are responsible for their own coronavirus-related policies.

ABC News' Ian Pannell and Sohel Uddin contributed to this report.

Scottish authorities arrested and charged Parliament Member Margaret Ferrier following an investigation that found she broke COVID-19 rules in September, according to the Police Service of Scotland.

Ferrier traveled between Glasgow and London twice while she had COVID-19 symptoms, and in the second instance was aware she had tested positive for the virus.

"We can confirm that officers today arrested and charged a 60-year-old woman in connection with alleged culpable and reckless conduct," a Police Scotland spokesperson said in a statement Monday. "This follows a thorough investigation by Police Scotland into an alleged breach of coronavirus regulations between 26 and 29 September 2020."

Ferrier, a member of the Scottish National Party, posted an apology on Twitter in October:

"On Monday evening I received a positive test results for COVID-19," she tweeted. "I travelled home by train on Tuesday morning without seeking advice. This was also wrong and I am sorry. I have been self-isolating at home ever since."

Ferrier was suspended by the Scottish National Party after information about her infraction came to light, but has so far resisted calls for her resignation.

-ABC News' Sohel Uddin contributed to this report.

Sandra Lindsay, director of critical care nursing at Long Island Jewish Medical Center in New York City, became the first person in the United States to complete a two-dose COVID-19 vaccine course outside of a clinical trial on Monday, 21 days after she was given her initial Pfizer/BioNTech vaccination on Dec. 14.

"I feel good," Lindsay told reporters Monday. "I don't feel any way different before I got it. I hope the vaccine is available to everyone as it was for me," she added.

The Pfizer vaccine has been shown to be 95% effective after two doses.

The United Kingdom saw another day of rising coronavirus cases, deaths and hospitalizations, according to the British government.

The nation recorded 54,940 new cases Sunday, bringing the total number of cases to 3,072,349, the health data showed. The seven-day average for new cases rose from 21,698 on Dec. 10 to 61,106 on Jan. 1, the British government said.

The U.K. saw 563 new COVID-19-related fatalities Sunday, according to the health data. The country has 81,431 total deaths since the start of the pandemic, the government said.

There are currently 32,294 people hospitalized in Britain. The seven-day average for new hospital admissions rose from 1,728 on Dec. 10 to 3,345 on Jan. 1, officials said.