New variant Omicron may increase the risk of re-infection with Covid-19


WHO: New variant Omicron may increase the risk of Covid-19 re-infection

The World Health Organization (WHO) has used the Greek letter Omicron to name a new variant of Covid-19 that has just been discovered in South Africa.

The Omicron variant identified by South African scientists contains more than 30 mutations in the spike protein. Photo: AFP

Accordingly, WHO has listed Omicron, with the original name B.1.1.529, on the list of worrying variants. Medical experts are extremely concerned about the transmissibility of the Omicron variant because it has a series of unusual mutations and the record shows that this variant is different from other worrying variants.

Maria Van Kerkhove, WHO’s Chief Technical Officer on Covid-19 emphasized in a video posted on Twitter that: “Omicron or B.1.1.529 is considered a worrisome variant because it has a number of worrying properties. hesitate”. “This variant has a large number of mutations, and some have some disturbing properties,” said Maria Van Kerkhove.

Health experts fear that the rapidly increasing number of Covid-19 infections in South Africa’s Gauteng province – where the Omicron variant was first discovered – means there is a risk that this variant is likely to evade. higher immunity than other variants. According to the WHO report, the number of Omicron infections is increasing in most provinces of South Africa.

It should be recalled that WHO only lists Covid-19 variants as of concern when they are more contagious, more virulent or evade public health measures, including vaccines and therapeutics. .

Data presented at a November 25 meeting organized by South Africa’s Ministry of Health showed that some Omicron mutations are more resistant to antibodies, which could reduce the effectiveness of the vaccine. resistant to Covid-19.

Certain mutations can also make Omicron more contagious. Many other mutations of Omicron hitherto have yet to be reported, leaving researchers unable to determine how they might affect variant behaviour, according to a presentation given at a meeting of the South African Ministry of Health.

“Preliminary evidence suggests that the risk of reinfection with this variant (Omicron – BTV) is increased compared with other worrisome variants,” WHO said in a November 27 statement. The agency says it will take weeks to understand how the Omicron variant affects diagnosis, treatment and vaccines.

South African scientist Tulio de Oliveira noted at a recent press conference that the Omicron variant contains about 50 mutations, but more than 30 of these are present in the spike protein, the region of the protein that interacts with human cells before entering into cells.

Furthermore, the receptor-binding domain (RBD) – the part of the virus that first comes into contact with human cells – has 10 mutations, much higher than the two for the Delta variant, which has spread rapidly. rapidly since the beginning of this year and become the dominant variant globally.

The above mutation in Omicron means that it most likely came from a patient who couldn’t get rid of the virus, giving it the opportunity to genetically evolve. This hypothesis has also been put forward for the Alpha variant before.

“There is a lot of work underway in South Africa and in other countries to better understand the new variant (Omicron – BTV),” said Maria Van Kerkhove, WHO’s Chief Technical Officer on Covid-19. , in terms of transmissibility, severity, and any impact on our countermeasures, such as diagnosis, treatment or vaccines”.

“There is very little information so far, but those studies are ongoing,” the WHO representative added.

About 100 Omicron variant genomes have been identified in South Africa, mainly in Gauteng province. This variant has also been detected in Israel, Botswana, and Hong Kong.

Many of the mutations identified in the Omicron variant are associated with higher antibody resistance, health officials said. This can reduce the effectiveness of the vaccine and affect how the virus behaves with vaccinations, treatments, and transmission.

“There are two approaches to what’s going to happen: Either wait for more scientific evidence or act now and,” said Sharon Peacock, professor of public health and microbiology at the University of Cambridge. withdraw later if not necessary”

“I think it’s better to go hard, roll it out early and fast, and apologize for mistakes, than the academic view that we need to get clear evidence before we act. Contagion. Rapid epidemics in South Africa could be due to super-spreading events or other factors,” she said.

Immediately after the initial information about the Omicron transformer, the European Union, the United Kingdom, Israel, Singapore, and the United States simultaneously applied travel restrictions for people from countries in southern Africa.

After the UK’s move, South Africa’s foreign ministry said that Britain “seems to have rushed to prevent the epidemic because even WHO has not yet given advice on next steps”.

In this regard, WHO recommends that countries should not rush to impose travel restrictions, but instead need to adopt a “scientific approach based on risk assessment”.