The new coronavirus variant identified in South Africa poses even more of a risk than the strain discovered several weeks ago in England, Britain's top health official warned on Monday. His alarm came as scientists warned that the new strain sweeping through South African coastal communities could be resistant to the COVID-19 vaccines approved or awaiting approval in the U.S. and Europe.

"I'm incredibly worried about the South African variant," Health Secretary Matt Hancock told BBC Radio. "This is a very, very significant problem... it's even more of a problem than the U.K. new variant." 

As the first doses of the Oxford University-AstraZeneca vaccine outside of medical trials were administered at an Oxford hospital on Monday, senior Oxford immunologist Professor John Bell — who helped create the prestigious university's vaccine — said there was a "big question mark" over whether the current versions of vaccines would work on the South African variant. 

He said it was "unlikely" the mutation would make the vaccines ineffective, but that they might need tweaks to provide as much protection against the strain as they do against the others already in wide circulation elsewhere.

The lead researcher on the trial of the Oxford vaccine carried out in South Africa, Professor Shabir Madhi, told CBS News on Monday that more than 13 variants of the coronavirus had been identified in the country since the start of the pandemic. He said the new one, 501.V2, which has spread like wildfire in South Africa's coastal cities, is the most worrying mutation of the virus so far. 

"It's not a given that the vaccine will not work on this variant, but it is a consideration that the vaccine might not have the full efficacy," he said. 

Well-timed trials

Both Oxford and U.S. pharmaceutical giant Johnson & Johnson have carried out human trials of their vaccines in South Africa, including doses given since the new variant started spreading discovered. 

"Those on our trial received the second dose during the time of this new variant, which is extremely fortunate," Madhi said, adding that he expected the relevant trial results by the fourth week of January.

Glenda Grey, President of the South African Medical Research Council and lead of the Johnson & Johnson vaccine trial team, confirmed that their trial also included giving participants doses amid the outbreak of the new strain.

"It is fortunate that this timing will allow us to see whether there is any change with this new variant" in the vaccine's efficacy, she said. Her team also expects results "towards the end of this month."

"This new variant should not delay vaccine access, but it also means we need to keep our eye on breakthrough infections," she said, referring to the rate of infections among those who have received the vaccine. 

Johnson and Johnson's vaccine requires only one dose, unlike the Oxford and Pfizer vaccines approved for use in Britain, or the Moderna formula being used in the U.S. along with the Pfizer shots.

The Oxford vaccine was trialed at seven different sites across South Africa in 2,100 volunteers, while some 45,000 people were involved in the Johnson and Johnson trial.

So far immunologists have voiced little concern over the efficacy of the approved or pending vaccines against other mutations of the coronavirus, including a variant discovered late last year in the London region that has driven U.K. infection rates up sharply. 

Government scientists say that, like the South African variant, the new British strain appears to be more easily passed between people, but they expect it to respond to the vaccines in the same way as the more widespread versions of the disease.

South Africans stuck waiting 

Meanwhile, South Africans are still waiting to learn when any vaccines might actually become available in their country outside of the trials.

The country's largest trade union has accused the government of "gross incompetence" with its a vaccine rollout plan. A group of eminent scientists, including Glenda Gray, slammed the government in an op-ed published on Sunday for what they said was an "astonishing" lack of planning.

Within hours of the criticism, Minister of Health Dr. Zweli Mkhize gave an online presentation outlining the government's plan. He said the goal was to vaccinate two-thirds of South Africa's 57 million people by the end of the year, beginning in February.

"We are targeting a minimum of 67% of the population to achieve herd immunity," he said.  

South Africa's Ministry of Health has reported a total of 1.1 million cumulative COVID-19 cases across the country, with a positivity rate of about 32% and almost 30,000 confirmed deaths. It's the worst national coronavirus epidemic in Africa.