Variant Omicron: everything you need to know

The Omicron variant detected in South Africa is rapidly spreading to Europe, it is classified as a worrying variant of Covid-19 by the WHO and has a high number of mutations. 

According to Public Health France , 91,608 new cases were confirmed on December 23, 2021. This is a record level since the start of the epidemic in March 2020. These are "the worst figures ever recorded since the start of the pandemic" declared the Minister of Health Olivier Véran. “ As the Delta wave begins to decline, the Omicron wave rises extremely quickly,” he added, specifying a doubling of positive cases “almost every two days” . The Omicron variant would be according to the first scientific studies "perhaps two and a half times less dangerous once it has been caught than the Delta variant" . But there,"although it may be half as dangerous as the Delta variant, if we have three, four times more patients, the pressure on resuscitation can only increase sharply".

Omicron: where does the name come from?

The WHO named this new variant. Omicron is the 15th letter of the Greek alphabet. This corresponds to the system put in place by the Organization since the appearance of the variants, and which makes it possible to "name and follow the genetic lines of SARS-CoV-2" as well as to make the names "more accessible to a non-scientific public. “ said the WHO . This process is also useful not to name the variant in relation to the geographical location where it was identified and to avoid stigmatization. Note that the two letters before Omicron, Nu and Xi, have not been assigned.

Omicron: where does it come from?

The Omicron variant, whose scientific name is B.1.1.529, was recently detected in people infected between November 14 and 22 in South Africa in the province of Gauteng where Pretoria and Johannesburg are located, according to the National Institute of Diseases. transmissible ( NICD ).

A variant that developed in HIV patients?

How to explain the appearance of this variant? Researcher Tulio de Oliveira, who discovered Omicron, has a hypothesis that it developed in people with HIV, we learn on Futurism . He followed with his team a patient insufficiently treated for the virus and therefore immunocompromised. Also infected with Covid, she remained positive for 216 days, during which time 13 mutations and around thirty genetic alterations were identified. This would therefore have provided a favorable evolution ground for the virus which would then have mutated into Omicron. Further research is needed to confirm this hypothesis.

Variant Omicron: more contagious?

According to virologist Tulio de Oliveira at a press conference conducted by the South African Ministry of Health, this new variant seems to be more contagious. "It includes more than 32 mutations in the Spike protein, compared to the first SARS-CoV-2", announced the Institut Pasteur in a press release dated December 20, 2021.

It is “a hybrid variant between the South African BETA and the DELTA. It presents mutation profiles somewhat similar to these two variants, in particular variants which concern the Spike protein, which is the key to entering the virus into cells” .

The Minister of Health, Olivier Véran announced that researchers are working on the subject to see if Omicron should be worrying. “When in doubt, we act as if this variant is potentially dangerous,” he said . Certain measures have been put in place, in particular a decree until at least Tuesday evening which prohibits flights from southern Africa to France.

The World Health Organization (WHO) has published a note on the Omicron variant and considers that to date it is classified as a variant of concern and poses "a very high risk" globally, but that no deaths have been reported. been reported.

According to the characteristics of this variant, “there could be future peaks of Covid-19 which could have severe consequences depending on different factors and in particular where these peaks would occur”. The WHO also indicated on December 12 that Omicron seems to be spreading more quickly than the Delta variant, which is currently responsible for the majority of infections in the world.

In South Africa, the Omicron variant replaced the other forms of Sars-Covd 2 within weeks. "Analyses in different countries indicate that the doubling time for cases is around 2 to 4 days. For example, more than 10,000 cases have been listed in England on December 15, 2021, where it should be the majority by the end of year 2021" , reports the Institut Pasteur.

At this time scientists do not know if the rate of diffusion is due to Omicron "escaping immunity, taking advantage of inherent higher transmissibility, or if it is a combination of the two" . However, it "is likely that Omicron will outperform Delta in settings where there is community transmission."

What symptoms?

If the variant seems more contagious than the others, it is not necessarily more dangerous in terms of its symptoms. According to South Africa's National Institute for Communicable Diseases , no unusual symptoms have been reported following infection with the omicron variant, and some individuals are asymptomatic. “To date, we have no knowledge of the pathogenicity of this variant because there are only a few cases yet,” said Olivier Véran.

The WHO reported on December 12 that symptoms were less severe with the Omicron variant. Also according to Dr Angélique Coetzee, president of the Medical Association of South Africa interviewed by The Telegraph , the variant causes mild symptoms: “the symptoms were different, milder than those previously treated” , such as body aches, a dry cough. On the other hand, she underlined great fatigue in the patients, but no loss of smell or taste. She also mentioned a case of fever and high pulse in a 6-year-old child. "I'm not saying there won't be serious illnesses but, so far, even the patients we've seen who weren't vaccinated have mild symptoms." "I'm sure a lot of people in Europe have this virus, but it was only poorly detected because we were on the lookout for Delta symptoms."