Boris Johnson, the British Prime Minister, stated that the vast majority of COVID-19 patients who ended up in intensive care had not got their booster vaccine, and advised people to get their vaccinations.

On a visit to a vaccine centre, Johnson said some doctors told him that up to 90% of COVID-19 patients in intensive care had not got their booster doses.

"I'm sorry to say this, but the vast majority of people who are currently ending up in intensive care in our hospitals are not boosted," he said. "I've spoken with doctors who say that the number of persons in intensive care is approaching 90%."

UK Prime Minister Boris Johnson and health minister test positive for coronavirus - ABC News

The highly transmissible Omicron variant of the virus is causing a surge in COVID infections in the UK, with 129,471 infections reported on Tuesday. There have also been anecdotal reports of people having difficulties obtaining tests.

While daily hospitalisation numbers have risen, they are still far below the crisis that hit hospitals earlier this year, with roughly 1,000 people admitted daily now, compared to 4,000 in January.

"The Omicron variant continues to create real problems, and you're seeing more cases in hospitals," Johnson said, "but it's clearly milder than the Delta variant."

He also advised people to be cautious on New Year's Eve after deciding not to impose tougher restrictions in England to combat the virus's spread. "I think everyone should enjoy the new year, but in a cautious and sensible manner. Take a test, consider ventilation, consider others, but most importantly, get a booster" he said.