Scientists in South Africa say there is a “reasonable concern” that the new variant of Covid-19 sweeping across the country might prove to be more resistant to current vaccines currently administered around the world, warning that this makes the need for a global roll-out of vaccines “even more critical.”
“It’s a theoretical concern. A reasonable concern… that the South African variant might be more resistant,” Prof Shabir Madhi, who has led trials for the Oxford-AstraZeneca vaccine in South Africa, told the BBC.
Prof Madhi was responding to comments by the UK government and scientists who said they are “incredibly worried” about the South African variant of the coronavirus that could evade vaccines.
The case surge in the UK is being driven by a new, more transmissible variant of coronavirus that apparently originated in Kent, England, and bears some similarities to the other variant, also believed to be in the country, but which first evolved in South Africa.
The South African variant is more likely to evade the vaccine than the new Kent variant, according to a key member of the Oxford vaccine team.
Sir John Bell, regius professor of medicine at Oxford, said that of the two, “I would worry a lot about the South African strain.”
Definitive answer probably in a matter of weeks
Prof Madhi said a definitive answer would probably come in a matter of weeks, with extensive testing already under way in South Africa.
The concern arises from the fact that the virus here has mutated far more than the variant in the UK, and one of those mutations might mean it can evade attack by antibodies that would normally fight coronavirus.
Vaccines teach the body to mount an immune response – which includes creating antibodies – to fight the coronavirus, should it ever encounter it.
Antibodies are small proteins made by the immune system that stick to the surface of viruses, effectively disabling them. If that ability to connect is weakened, then the antibodies created following the introduction of a vaccine might not be as effective.
Not useless but might weaken impact
Prof Madhi said it was “unlikely” that the mutation in South Africa would make the current vaccines useless, but might “weaken the impact.”
A vaccine expert at Wits University, Prof Helen Rees, said: “Fortunately, should further modifications of the vaccine be required to address the new variants, some of the vaccine technologies under development could allow this to be done relatively rapidly.”
South Africa recently angrily pushed back against suggestions from the British government that its variant was more transmissible than the one in the UK.
Scientists also insist there is no evidence of that, nor that the mutations here have made the virus deadlier.
Prof Rees said concern about the mutations in South Africa should add to global pressure for a swift roll out of vaccines across the world, and not just to wealthier nations.
“As the new variants are already spreading to other countries, the importance of ensuring that vaccines remain effective against new variants is a global imperative.”
Prof Barry Schoub, who chairs the SA government’s advisory committee on vaccines, said the “preliminary evidence” from tests did not suggest that mutations would allow the virus to ‘escape’ the impact of the current vaccines.
“The vaccines seem to be very effective,” he said, citing laboratory tests that appeared to show the current vaccines can still “neutralise this new variant.”
Prof Madhi said crucial laboratory experiments were yet to get underway and the efficacy of the vaccines would only be known “over the next few weeks.”