Covid Omicron: What do we know about the new variant of Covid, the Omicron: according to experts, it is likely that the shield offered by vaccines against serious forms of the disease is still high
Omicron’s Italian “patient zero” had already received two doses at the time of the infection in South Africa. Should we fear that the new variant will escape vaccines?
It will take a few weeks to answer this question, but the companies that produce mRna vaccines are already working on a preparation specifically directed against Omicron that could be ready – according to Pfizer – in “a hundred days”.
The possibility that the strain “holes” the protection offered by current vaccines is however considered remote by experts.
“It is more likely that the virus partially escapes the immune defense, as already happened in the Delta infection in which the effectiveness of vaccines has dropped compared to previous variants, but the defense against serious disease has remained high – explains Sergio Abrignani, full professor of Immunology at the State University of Milan and director of the National Institute of Molecular Genetics “Romeo and Enrica Invernizzi” -.
In the case of Omicron, a further decrease in protection against infection is possible, but still a good defense against severe disease.
The new strain has 32 mutations in the Spike – is it worrying? – Covid Omicron
It is not certain that all mutations are “negative”, or that they make the virus more transmissible or pathogenic.
Omicron has some characteristics common to the Beta and Gamma variants (those considered more “dangerous”), but to understand the ability of current vaccines to protect against infection and disease, further data on the protective effect of antibodies and T lymphocytes are needed.
“Neutralizing antibodies inhibit infection by preventing the virus from entering cells, while T lymphocytes are also needed to protect against the disease, which kills already infected cells – clarifies Abrignani -: neutralizing antibodies mostly recognize the very region mutated Spike binding to human cells.
Is the third dose of the vaccine protective, even if not “perfect” for Omicron?
Yes, because it strengthens the immune response which, as mentioned, also affects areas of the virus unchanged compared to the original strain, that of Wuhan. A possible Omicron spike-specific vaccine – such as those announced by Pfizer and Moderna – could be used for the fourth dose.
Is it theoretically possible that Covid Omicron causes more severe symptoms?
Do we risk new lockdowns?
Is it possible that the Covid Omicron variant developed, as hypothesized by geneticist François Balloux of University College London, in an immunocompromised individual, perhaps because of untreated HIV / AIDS?