CDC raises UK travel warning to highest level amid COVID-19 surge

On Monday, the U.S. Centers for Disease Control and Prevention raised its travel warning for the United Kingdom to the highest level just as the British government lifted most COVID-19 restrictions after more than a year of lockdowns. 

Despite the lifting of restrictions, many medical experts are calling the move premature as the country faces a surge in COVID-19 cases. 

"Because of the current situation in the United Kingdom, even fully vaccinated travelers may be at risk for getting and spreading COVID-19 variants," the CDC wrote in a press release. 

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Beginning Monday, face masks were no longer required in England, work-from-home guidance ended and — with social distancing rules shelved — no limits existed on the number of people attending theater performances or big events.

Nightclubs were allowed to open for the first time in almost 18 months, and from London to Liverpool, thousands of people danced the night away at "Freedom Day" parties starting at midnight.

Prime Minister Boris Johnson, who has dialed down talk of freedom in recent weeks, urged the public to "proceed cautiously" and "recognize that this pandemic is far from over."

COVID-19 cases are on a rapid upswing because of the highly infectious delta variant first identified in India. Cases topped 50,000 per day last week for the first time since January. Deaths remain far lower than in the winter thanks to vaccines, but have risen from less than 10 a day in June to about 40 a day in the past week.

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Still, British officials have repeatedly expressed confidence that the U.K.’s vaccine rollout — 68.5% of adults, or more than half the total population, has received two doses — will keep the threat to public health at bay. But 1,200 scientists from around the world backed a letter to the British medical journal The Lancet criticizing the Conservative government’s decision.

"I can’t think of any realistic good scenario to come out of this strategy, I’m afraid," said Julian Tang, a clinical virologist at the University of Leicester. "I think it’s really a degree of how bad it’s going to be."

The end of restrictions in England is a critical moment in Britain’s handling of the pandemic, which has killed more than 128,000 people nationwide, the highest death toll in Europe after Russia. Other parts of the U.K. — Scotland, Wales and Northern Ireland — are taking slightly more cautious steps out of lockdown and keeping mask requirements for now.

In a reminder of how volatile the situation is, the prime minister was spending "Freedom Day" in quarantine. Johnson and Treasury chief Rishi Sunak are both self-isolating for 10 days after contact with Health Secretary Sajid Javid, who has tested positive for COVID-19.

Johnson initially said he would take daily tests instead of self-isolating — an option not offered to most people — but U-turned amid public outrage.

The prime minister is among hundreds of thousands of Britons who have been told to quarantine because they have been near someone who tested positive. The situation is causing staff shortages for businesses including restaurants, car manufacturers and public transport.

Globally, the World Health Organization says cases and deaths are climbing after a period of decline, spurred by the delta variant. Like the U.K., Israel and the Netherlands both opened up widely after vaccinating most of their people, but had to reimpose some restrictions after new infection surges. The Dutch prime minister admitted that lifting restrictions too early "was a mistake."

In the U.S., many areas abandoned face coverings when the Centers for Disease Control and Prevention said fully vaccinated people didn't need to wear them in most settings. Some states and cities are now trying to decide what to do as cases rise again.

This story was reported from Los Angeles. The Associated Press contributed.