South African Covid variant: Everything we know so far
The government has sought to reassure the public over its vaccine programme amid mounting concerns surrounding the South Africa coronavirus variant.
Early data from a small trial indicates that the vaccine offers "minimal protection" against mild and moderate disease caused by the variant, known as B.1.351.
Oxford University has said it is redesigning its current vaccine to neutralise B.1.351, and that the updated version of the jab will be ready by autumn.
"While it is right and necessary to prepare for the deployment of an updated vaccine, we can take confidence from the current roll out and the protection it will provide all of us against this terrible disease," Nadhim Zahawi, the vaccines minister, said.
What are the facts?
Scientists have agreed more research is required into the level of protection the Oxford vaccine affords against the South African variant, but some expressed have concern over the preliminary findings from the southern hemisphere.
A study of 2,000 people, who were were mostly young and healthy, found that the vaccine showed "limited efficacy against mild disease primarily due to the B.1.351 South African variant".
The results appeared to confirm theories that mutations seen in South Africa will allow for ongoing transmission of the virus in vaccinated populations.
However, the study did not provide clarity on whether the vaccine was effective against severe disease caused by B.1.351, given that the trial participants had an average age of 31 and were deemed at low risk from such an outcome.
Shabir Madhi, who led the research in South Africa, said when looking at whether it could prevent severe disease, the vaccine could be compared to the one made by Johnson & Johnson which has proved effective.
"There's still some hope that the AstraZeneca vaccine might well perform as well as the Johnson and Johnson vaccine in a different age group demographic that I address of severe disease," he said on Monday.
Similarly, health minister Edward Argar said there is “no evidence that this vaccine is not effective in preventing hospitalisation and severe illness and death, which ultimately is what we're seeking with these vaccines today”.
South Africa has meanwhile suspended the rollout of the British-designed vaccine to healthcare staff following the results, which have yet to be peer reviewed.
The country received its first one million doses of the vaccine at the end of January ahead of a planned rollout to frontline health workers from the middle of February.
What do we know about the new variant?
B.1.351 is thought to be as transmissible as the variant that was first identified in Kent.
Initially detected in South African swab samples from October 2020, it has obtained a series of notable mutations in its spike protein – the part of the virus responsible for binding and entering human cells.
This includes the E484K mutation, which changes the shape of the protein in a way that makes it less recognisable to the body’s immune system.
As a result, the South African variant is capable of evading parts of the immune response triggered by vaccination or natural infection.
The vaccines that have been approved to date are still capable of offering protection against B.1.351, but various analysis and trial studies have suggested they may not be as effective.
How widespread is B.1.351 in the UK?
Mr Argar said the latest figure for the number of cases of the South African coronavirus variant in the UK is 147.
"It's a very small number but it's still something we quite rightly have got to keep a very close eye on,” he told the BBC.
However, it’s highly likely that there are more infections caused by B.1.351 in other parts of the country that have not yet been picked up.
Scientists sequence up to 10 per cent of all positive cases as part of the UK’s genomics surveillance programme.
This means there is “a high probability that further local cases are in circulation, making it more difficult that the spread of the variant can be contained,” according to Rowland Kao, a professor of veterinary epidemiology at the University of Edinburgh.
Worryingly, authorities in England have also found evidence of community-based transmission.
Eleven people with no travel links to South Africa were found to have been infected with B.1.351 earlier this month.
The infections were picked up in eight different English postcodes, suggesting that the new variant may now be spreading in local pockets of the population – rather than being imported via travellers to Britain.
Experts believe the cases may have second or third generation connections to South Africa but detailed investigations have not confirmed this.
The infections were been detected in the following eight areas: Hanwell, Tottenham and Mitcham in London; Walsall, West Midlands; Broxbourne, Hertfordshire; Maidstone, Kent; Woking, Surrey; and Southport, Merseyside.
Community spread of B.1.351 is to be expected on account of its transmissibility and stealth-like nature in passing from one person to another before the onset of symptoms.
Dr Julian Tang, a virologist at the University of Leicester, said the spread of the variant among people with no travel history “is not surprising and was somewhat inevitable once we heard about the identification of some imported cases a few weeks ago in the UK.”
Although only 11 community-based cases have been detected, it’s highly probable there are many more infections circulating undetected in each of the different areas identified by health authorities.
“So for every case we identify, there may be many others infected depending on the amount of pre-symptomatic/asymptomatic contacts that have occurred,” said Dr Tang.
What does mean for the vaccine rollout?
For now, the current lockdown measures in place will prevent B.1.351 from spreading like wildfire, as was the case with the British variant before Christmas, but its presence within the community is of concern for when the UK opens up again.
Pockets of the population will remain vulnerable to the virus, having not been previously infected or vaccinated, and may allow B.1.351 to continue circulating.
Given its high transmissibility, the South African variant could fuel a third wave of infections and hospitalisations that once again overwhelms the NHS – especially if restrictions are lifted too quickly and people begin mixing in public spaces.
Of course, the UK’s cause is helped by the impressive roll out of the Covid-19 vaccines, with figures showing that more than 12 million people have now received a first dose.
Trial studies have meanwhile shown that vaccines produced by Johnson & Johnson, Moderna and Novavax still offer protection against B.1.351 – roughly 60 per cent in the case of the latter – but are not as effective as they were against the original form of the virus.
Even so, both Johnson & Johnson and Novavax have reported that none of the people who received a vaccine in their South African trials died of Covid-19.
Indeed, even with lower efficacy rates, there is optimism that all six of the vaccines to have released positive trial results will either prevent or reduce hospitalisations and deaths among those exposed to B.1.351.
If further analysis and data confirms this, that’s a big win for the public and will ensure that life can start to gradually return to some degree of normality later this year – though the ability of B.1.351 to reinfect people (but not necessarily cause illness) will remain a threat that authorities must consider when easing restrictions.
What next?
Dr Susan Hopkins, of Public Health England, has said the UK was looking at whether those who had already taken a Covid-19 vaccine would need a fresh shot to cover the risk posed by new mutations.
"It is unlikely that people would have to start [the vaccine treatment] again, it is much more likely that it would be a booster shot – a bit like the annual flu vaccine," she said earlier this month.
Mr Argar similarly said it "would not be unreasonable" to have annual coronavirus booster jabs to protect against new variants that emerge.
For now, the main objective is identifying cases of B.1.351, both symptomatic and asymptomatic, that are circulating in Britain and acting fast to cut its chains of transmission.
The decision to implement “surge” testing in the eight affected areas of England will give authorities a better idea of how widespread the South African variant is, and it’s crucial that local residents follow government calls to come forward and get tested.
Local health teams will be carrying out door-to-door screening while mobile testing units are to be introduced to each area in a bid to pick up any further infections linked to B.1.351.
“This spread, even if small in scale, needs to be brought under control quickly, so Public Health England’s house-to-house checks, and intensive testing are the right thing to do,” said Simon Clarke, a professor in Cellular Microbiology at the University of Reading.
