UK claims South Africa's COVID variant more dangerous, latter rejects
South African Health Minister Zweli Mkhize has strongly rejected UK Health Secretary Matt Hancock's claim that the African country's new coronavirus strain is more contagious than the one in the United Kingdom. The development comes at a time when the new virus strain has spread to more countries, with Japan, Germany, Switzerland, Denmark, Netherlands, Belgium, and Australia detecting cases of the UK-linked variant. Here's more.
- 'Appears to have mutated further': Hancock on South African strain
- Three new strains of coronavirus detected so far
- No evidence that 501.V2 is more transmissible: Mkhize
- Unusually high mutations found in the UK strain
- Spike protein changes in other two variants
- Increased transmissibility could cause large increase in incidence
- Here's what the European Centers for Disease Control stated
- Possible explanation for emergence of new variant
- Will the existing vaccines work against new COVID strains?
'Appears to have mutated further': Hancock on South African strain
Earlier, Hancock announced restrictions on travel from South Africa, saying the COVID variant there was "highly concerning, because it is yet more transmissible, and...appears to have mutated further" than the UK's strain. As many as 50 countries have banned to and from the UK so far over the new coronavirus variant. However, scientists are yet to determine if these mutated variants are more dangerous.
Three new strains of coronavirus detected so far
So far, three new coronavirus strains with the N501Y mutation have been discovered across the world. They include the UK's B.1.1.7, or VOC202012/01, which is reportedly present in at least seven countries. There's also the 501Y variant that's been seen in the UK's Wales. Then there is South Africa's 501.V2 variant, which has been found only in the African country, as per genomic surveillance.
No evidence that 501.V2 is more transmissible: Mkhize
"At present, there is no evidence that the 501.V2 (variant) is more transmissible than the United Kingdom variant -- as suggested by the British health secretary," stated Mkhize. "There is also no evidence that [it] causes more severe disease or increased mortality than the UK variant or any variant that has been sequenced around the world," the South African minister added.
Unusually high mutations found in the UK strain
It is interesting to note that the UK's B.1.1.7 variant underwent 17 changes/mutations, especially in the spike protein, which is unusually high. The spike protein allows the virus to attach more strongly to human cells, leading to infection. However, the lineage of the South African and Welsh variants is distinct from the UK variant; these variants don't even include some of the same mutations.
Spike protein changes in other two variants
The South African variant also has a high number of mutations, including changes in spike protein, which may increase its transmissibility. Even the Welsh strain, which has reportedly been around for a few months but didn't spread rapidly, also showed changes in spike protein.
Increased transmissibility could cause large increase in incidence
London School of Hygiene and Tropical Medicine's researchers found that while the UK variant is 56% more transmissible, there's no evidence yet that it leads to more serious disease cases. "Nevertheless, the increase in transmissibility is likely to lead to a large increase in incidence, with COVID-19 hospitalizations and deaths projected to reach higher levels in 2021 than were observed in 2020," they said.
Here's what the European Centers for Disease Control stated
While the UK variant's origin remains a mystery, a new threat assessment report by the European Centers for Disease Control (E-CDC) says SARS-CoV-2's mutation rate is two changes per month, as per "molecular clock estimates." "Random mutations acquired during circulation of the virus would not explain the unusually high...spike protein mutations," it said, adding it's also "not very likely due to global travel patterns."
Possible explanation for emergence of new variant
"One possible explanation for the emergence of the variant is prolonged SARS-CoV-2 infection in a single patient, potentially with reduced immunocompetence, similar to what has previously been described. Such prolonged infection can lead to accumulation of immune escape mutations at an elevated rate," E-CDC said.
Will the existing vaccines work against new COVID strains?
Determining the new COVID variant's origin will be crucial for preventing further mutations and ascertaining what implications the mutations might have on the pandemic and efficacy of the existing vaccines. However, major vaccine makers stated their vaccines will still work against new strains. BioNTech CEO Ugur Sahin said if their vaccine fails to provide adequate protection, they could reset the shot within six weeks.
