Infection, risk, effectiveness of vaccines and treatments … What do we know about the Omigran variant in six questions?

Orange, with media services Released Sunday, December 19, 2021 at 7:00 p.m.

LANDMARKS. A month after being identified, this new strain looks and feels very contagious Partial escape from vaccines.

A large unknown remains: the severity of the infection.

1. Where does the Omigron variant come from?

This is the latest version of SARS-CoV-2 (the corona virus that causes goiter) Identified in late November in Botswana, Then in South Africa. Its uniqueness lies in the early strain of the virus known as Wuhan and its high number of mutations compared to previous variants such as the delta, which has largely dominated global pollution since the summer of 2021.

It is not known exactly where and how Omigron appeared. One hypothesis fascinated many scientists: the virus would have gradually evolved at low noise In the body of a person with an immune deficiency, A process that takes several months to develop a significantly different version from the initial strain.

2. Is it more contagious than previous variants?

It is obviously very contagious. This was only a hypothesis when it first appeared, but considering the epidemic situation in many countries, it was confirmed in the first weeks of December. Omigron is spreading “at a rate we have never seen in any other way” and “can be found in most countries,” World Health Organization (WHO) Director-General Tetros Adanom Caprais warned this week. It has so far been found in 80 countries.

South Africa and its neighbors recorded the eruption of Govt cases with the arrival of Omigran, which saw meteor rises in many European countries. This is the situation in Denmark and the United Kingdom. In more detail, Omigron Can dominate Europe According to European Commission President Ursula van der Leyen, in mid-January.

3. Will he definitely replace Delta?

It’s more likely, but scientists suggest other possibilities: Omigran changes its precursor for a while, but returns it, or both variants work together, as do some strains of the seasonal flu virus.

4. Are vaccines effective?

This is one of the biggest challenges posed by Omigran, as current vaccines against delta variant infections are already losing their effectiveness over time. Mutations in Omigran significantly reduce antibody immunity to the virus. In effect, it is People who have been infected with the virus before can become infected again And affects a large number of vaccinated people. Several recent studies conducted in the laboratory support this last hypothesis. They show a decline in antibody levels against Omicron in people who have been vaccinated with AstraZeneca or Sinovac by Pfizer / BioNTech, Moderna and many more.

As Pfizer and Bioendech in particular have reported, booster doses seem to clearly boost immunity through antibodies, but we are far from sure how long this effect will last. However, this does not mean that vaccines lose all of their effectiveness. Because antibodies are only part of the immune response, it contains cells called D lymphocytes.

In fact, a study published this week in South Africa suggests that the Pfizer / BioNTech vaccine may be more effective against severe forms developed by Omigran, including the first two doses.

5. Can treatments cure this variation?

Omigron seems to cause difficulties with synthetic antibody treatments, especially for patients who have already been hospitalized. On the other hand, one can hope that it will not oppose the anti-govt pills recently announced by Merck and Pfizer Labs. However, this is a hypothesis, linked to the activity of these drugs, which still needs to be supported by facts.

6. Is it less dangerous?

It is now The big unknown. Medical reports from the past few weeks have made it clear that Omigran is no more dangerous than its predecessors, including Delta. According to the famous American scientist Anthony Fossie, it is “almost certain”, even believing it to be less dangerous.

But should we bet on this event? This is a risky bet. Already, Omicron is certainly not painless, as shown by the first death recorded in the UK earlier this week. After all, scientists warn against an optical effect. If Omicron is less dangerous but more contagious, its effects can be severe at the joint level.

“We are worried Because people think Omicron is harmless, “the WHO boss is worried.” Although Omicron causes less severe symptoms, The number of cases could again plunge health systems Who is not ready. ”