After these two "waves" of Delta variant, will the sixth be that of B.1.1529?
It is far too early to answer them, but this new version of SARS-CoV-2 has just been identified in South Africa and it has several characteristics that could make vaccines less effective.
However, as always, we must remain very careful when a new variant appears.
We take stock.
What are the peculiarities of this variant?
The virus is constantly evolving, and when it replicates, "mistakes" may be made.
In this case, it leads to mutations, that is, the genome is changed in a given place.
These mutations can in particular occur at the level of the Spike protein, which is particularly sensitive because it is targeted by vaccines.
This variant B.1.1529, which could be given a name taken from the Greek alphabet by the World Health Organization (WHO) in the coming days, was officially identified this Thursday by South African scientists.
It groups together 32 mutations at the level of the Spike protein.
A profile deemed "really horrible" by Tom Peacock, virologist at Imperial College.
Read also Covid-19: after Delta, should we fear even more dangerous variants?
"Some of these mutations are associated with immune escape
(and therefore resistance to vaccines)
, but we are not really able to predict their real impact", indicates to Parisian Etienne Simon-Lorière, head of the genomics unit evolution of RNA viruses at the Institut Pasteur.
Other mutations, sported by previous variants like Alpha and Delta, are known to be able to make the virus more contagious.
Prof @Tuliodna is giving an insightful overview of the #NewVariant # B11529 pic.twitter.com/VnFBrj2pOT
- NICD (@nicd_sa) November 25, 2021
However, we will have to wait a bit to find out more.
"Although the data is limited, our experts are working overtime to understand what the potential consequences could be with this new variant," Professor Adrian Puren, acting executive director of the National Institute of Communicable Diseases said Thursday. South Africa.
The results of ongoing studies could be known within "two to three weeks," according to British epidemiologist Meaghan Kall.
Where has it already been identified?
A hundred sequences of this variant, that is to say positive cases passed under the very fine radars of scientists, have been identified in total in three countries: in Bostwana, in Hong Kong, and especially in South Africa. In several regions of this country, new positive cases are increasing “exponentially” and the share of B.1.1529 among sequenced positive tests is increasing very sharply. Clearly, this variant seems to have the capacity to take precedence over Delta, which has been particularly transmissible and hegemonic for several months in much of the world.
4. Here's how variants have spread in SA:
1. Light gray: lots of different types of virus (1st wave)
2. Green: 2nd wave (Beta)
3. Red: Delta, 3rd wave
4. Yellow: C.1.2 ( still detected at low levels, but not increasing)
5. Blue: B.1.1.529 (increasing fast) pic.twitter.com/osjXNUJmiL
- Mia Malan (@miamalan) November 25, 2021
“A few days ago, we weren't very worried.
There it is true that we have this signal to follow very closely ”, indicates Simon Etienne-Lorière.
However, the expert remains cautious in view of the sequencing data, not all the positive cases being analyzed in detail.
It is therefore possible that the actual share of variant B.1.1529 among the contaminations identified in South Africa is lower than that which appears in the results of the sequencing.
"Maybe they are sequencing specifically if this variant is suspected, so maybe the proportions are different.
But B.1.1.529 seems to succeed in spreading competitively ”, indicates the scientist.
And in France ?
No case of this variant has yet been identified in France, and Public Health France has never mentioned it in its risk analyzes.
“We put him on the list to watch him, but we don't expect to see him arrive right away because South Africa is an English-speaking country with which we don't have a lot of contact.
But it can go very quickly, ”says Etienne Simon-Lorrière.
For several months, health agencies in France but also in many foreign countries have, however, been able to demonstrate responsiveness when a new version of SARS-CoV-2 was detected.