Battling the Kent variant of coronavirus is the government's biggest concern, a minister has revealed.

Almost 150 people across the country are understood to have contracted the highly infectious South African strain of the illness, sparking fears it may spread faster and be more resistant to vaccines than other mutations.

But Environment Secretary George Eustice has said today that battling the strain of the deadly illness that originated in the South East continues to be Number 10's "primary challenge".

The senior Tory explained: "Our main challenge at the moment is dealing with the so-called Kent variant, which is highly infectious, spreads more quickly than some of the other variants and dominates at the moment.

"It is our primary challenge - and the vaccines are fully efficacious against that particular strain.

"We constantly monitor other variants around the world.

"There is always a risk that there will be a variant that manages to circumvent the vaccines we have, that’s why we have to constantly redouble our efforts to evolve the vaccines so they can deal with any new variants that might arrive.

"It is also why we are constantly toughening our approach to quarantine for those arriving from overseas because until we have an ability to vary the vaccine and update the vaccine to meet those challenges, we have to exercise some caution about international travel."

This comes after the deputy chief medical officer for England, Prof Jonathan Van-Tam, told a news briefing yesterday that the South African mutation is unlikely to become dominant in the UK over the coming months.

Unlike the strain that emerged in Kent, he said, it did not enjoy a “transmissibility advantage” over other variants.

Prof Van-Tam also stressed it was “likely” that the existing vaccines would be effective in preventing serious illness in people who became infected with the new South African strain.

“Early data does not suggest the South African variant has a distinct transmissibility advantage over our current virus,” he added.

“Because of that there is no reason to think that the South African variant will catch up or overtake our current virus in the next few months.

“Our immediate threat is from our current virus and there is now plenty of evidence that the vaccines that we are deploying are effective against our current virus.”

A door-to-door testing campaign was carried out in Maidstone last week after a resident - who had not travelled overseas or been in contact with anyone who had - tested positive for the variant.

More than 9,600 kits were delivered to homes in the ME15 area as part of the operation. It is not yet known if it uncovered any further cases of the mutation.

Mr Eustice continued: “We can’t be complacent, but the evidence so far suggests that the South African variant is less contagious than the Kent one and hasn’t got that highly infectious rate that we see in the Kent variant."

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