Covid-19: why the new variants worry the health authorities so much
While the circulation of the British variant worries scientists and doctors, the emergence of new mutations in the SARS-CoV-2 virus makes the situation even more worrisome. Explanations.
SARS-CoV-2 has certainly mutated many times before, and there is nothing abnormal about it: it is characteristic of RNA viruses. But some variations of the virus, which are more contagious, gain traction by spreading widely. This is the case with the English variant: the first case was reported in mid-December in the UK, and it only took a few weeks for it to become the majority in the country and spread to many countries.
South African and Brazilian Variants: What We Know
On December 18, a first case attributed to the South African variant of the virus was notified to the WHO. It has been in circulation since August. Since then, this variant called 501YV2 has also circulated in several countries.
Scientists say this new strain of coronavirus is of particular concern. According to the president of the Scientific Council and immunologist Jean-François Delfraissy, there is no certainty about the efficacy of vaccines against this variant of the virus "probably still a little more toxic than the English virus".
At the source of the scientists concerns, the E484K mutation, common to the South African variant and the Brazilian variant detected in the Spike protein, is in the small spike that allows it to enter cells more easily while escaping the antibodies. The first tests carried out in the laboratory seem to indicate that this variant would have the ability to fool the antibodies and interrupt their mission.
Covid-19: and now, the Los Angeles variant
According to the New York Times, a new variant of the SARS-CoV-2 virus is believed to be spreading in California, where the Covid-19 epidemic is in full swing. Called L452R, it is said to be highly contagious, to the point of accounting for at least a quarter of cases in the state to date, compared to just 3.8% at the end of December.