One letter, three dots, five digits. Around the world, there is a concern response to B.1.1.529, a new variant of the coronavirus discovered in South Africa. A growing number of infections with this variant is causing fairs to fall and aircraft from southern Africa are no longer allowed to take off to a growing number of destinations.
A working group of the World Health Organization (WHO) that maps out mutations of the virus meets today. B.1.1.529 may be assigned a letter from the Greek alphabet, if the working group identifies it as a variant or interest or even a variant or group. What is known so far about B.1.1.529?
In recent weeks, the number of positive tests in South Africa has suddenly increased considerably, especially in the province of Gauteng. Upon closer inspection of the samples, there was a virus variant that had not been found before in 77 cases. That number seems small, but at the same time, the number of positive tests across South Africa increased from a few hundred a day to already a few thousand.
South African experts suspect that those two developments – a new variant and a large increase in infections – could mean that the virus is more contagious than previous variants. Meanwhile, the virus has also been found in other countries. Four cases are known in Botswana. Two cases were found in Hong Kong and one in Israel, coming from travellers from southern countries in Africa. In Belgium, too, has been a positive test with the new variant.
In addition, 32 changes have been found on the so-called spike protein compared to the original virus. With the spike protein, the virus attaches to human cells. The current vaccines are designed to produce antibodies that target the spike protein.
32 mutations sound a lot, but “whether those mutations are a problem is still anybodys guess,” says Eric Snijder, professor of molecular virology at LUMC. Other variants such as the alpha and delta variants had ten to fifteen changes from the original virus. “We have now been many months on and evolution is continuing steadily.”
Minister De Jonge explains why a flight ban has been introduced:
part, the mutations found were also found in other variants, says virologist Marion Koopmans. She is part of the WHO team that determines whether this variant is classified as worrying. “Some of those mutations can make antibodies less easily bind to the spike protein.” However, Koopmans wants to watch to make conclusions to that now: “It remains to be figured out what consequences the mutations have.”
It is important, for example, whether it affects the vaccines: “With delta, protection against infection decreased slightly, but protection against serious illness remained in place.”
Consequences of mutations still unknown
Before there is certainty about whether this variant is more contagious, why and what the consequences are, months can go over it, says Snijder. For example, mutation N501Y was found in multiple variants, such as alpha, beta and gamma and was suspected to play an important role in the higher degree of spread. “Only recently did the evidence for that come through,” says Snijder.
According to Koopmans, it will take at least a few weeks before we know more about the infectiousness. The epidemiological development in South Africa is worrying, but there may be other explanations for the rapid increase in the number of infections than biological properties of this variant: “You should always look for that.”
In addition to monitoring the epidemiological situation, lab studies must also be done, says Koopmans: “Cells are then infected with different variants and then it is checked if one variant displaces the other.” Before you can perform those tests, you do need virus material that needs to be grown first.
Eric Snijder also suspects that we will only have more certainty about this variant in a while: “The fastest thing is to do tests with animal models. But that can also take weeks to months. If you want to take precautions, you cant wait for that.”
Whether a flight ban helps is uncertain, Snijder and Koopmans think. Earlier variants were also not stopped by it. “That doesnt mean you cant try a flight ban, but the question is whether it makes sense,” says Koopmans. And there is evidence that the virus is already spread further than we can see.
B.1.1.529 is not a direct relative to the globally dominant delta variant, but is more similar to older variants. From the source in China, several branches have emerged, Snijder explains: “We had the dominant branches in good picture, but onplaces where we have less visibility of it may be that the virus has developed in a different way.”
B.1.1.529 may have emerged in a different place, but now more or less accidentally discovered in South Africa, because there is a lot of sequencing – mapping the genetic material of the virus. Koopmans points out that various differences have also been found within the samples of B.1.1,529: “It may mean that it has been breeding under the radar for a long time.”
Eric Snijder thinks that too: “This doesnt happen in one night. And there is no reason to believe that the virus has evolved.”