Risk of 'vaccine-busting' coronavirus variants prompt tougher UK quarantine: Johnson

British Prime Minister Boris Johnson said on Monday he was looking at toughening border quarantine rules because of the risk of "vaccine-busting" new coronavirus variants.

New variants of the virus that causes Covid-19 are opening up the prospect of a much longer battle against the pathogen than previously thought. Scientists fear the new variants may be more deadly, and that vaccines may be less effective against them.

"We have to realise there is at least the theoretical risk of a new variant that is a vaccine-busting variant coming in - we've got to be able to keep that under control," Johnson told reporters at a vaccination centre.

"We want to make sure that we protect our population, protect this country against reinfection from abroad," Johnson said. "We need a solution."

The new variant identified in South Africa can evade the antibodies that attack it in treatments using blood plasma from previously recovered patients, and may reduce the efficacy of the current line of vaccines, scientists said.

Besides the South African variant, others have been identified in Britain and Brazil.

British scientists and politicians have expressed concern that vaccines being deployed or in development could be less effective against the variant.

Johnson said the British government was looking at the option of quarantine hotels - where inbound travellers pay to be isolated at a hotel on arrival. In Australia, arrivals have to quarantine for a minimum of 14 days at a hotel.

"That idea of looking at hotels is certainly one thing that we are actively now working on," he said.

Johnson said the United Kingdom was on target to reach its vaccination targets for vulnerable groups by Feb. 15.

"We are on target to hit our ambition," he said.