Omikron: This dead vaccine is hardly effective against the corona variant

Created: 12/28/2021 Updated: 12/28/2021, 1:26 PM

From: Sophia Lother

How well did inactivated vaccines protect against the Corona variant Omikron?

One study does not provide good news for either of these vaccines.

Frankfurt - The Corona variant * Omikron is spreading rapidly around the world. It has a particularly large number of mutations, especially on the spike protein. According to the Robert Koch Institute, some of these amino acid changes are known to have an impact on transmissibility and immune escape. With the advent of the omicron variant, the concerns of many increased that the corona vaccines * used to date might also be less effective in protecting against corona infections and severe Covid-19 courses.

So far it is known:

Due to the omicron variant, some vaccines, such as those from Biontech / Pfizer and Astrazeneca, * may no longer have such a strong effect, which is why a booster vaccination is urgently recommended.

According to an international study, the vaccine from Moderna is particularly suitable against the Corona variant Omikron. * But other players have now entered the vaccine market.

In addition to protein vaccines such as Novavax, * which work on the basis of viral protein particles produced in the laboratory, there are also so-called dead vaccines.

One of them is Coronavac from the Chinese manufacturer Sinovac.

But especially on this dead vaccine, a study is now delivering downright devastating results.

Dead vaccine Coronavac hardly works against Omikron: How does the Corona vaccine work?

Inactivated vaccines work on the basis of inactivated, i.e. killed, coronavirus pathogens. This is how the classic, well-known vaccines against tetanus or whooping cough work. As early as spring 2021, the WHO issued emergency approval for Coronavac, among other things. However, previous research has already shown that these dead corona vaccines have some disadvantages *. In October 2021, a study in the journal Nature showed that the protection against infection is lower with the dead vaccines than with the mRNA vaccinations from Biontech / Pfizer and Moderna * or the vector vaccine Astrazeneca. * Other studies came to the conclusion that the amount of neutralizing antibodies in dead vaccines is lower.

In Brazil, too, work is being carried out on the production of the corona inactivated vaccine Coronavac.

© Instituto Butantan / Picture Alliance / dpa

The Omikron variant did not yet exist at that time, of course.

This has changed now.

Researchers from Hong Kong compared the effectiveness of the vaccine from Biontech / Pfizer * with the effect of Coronavac from Sinovac.

For this purpose, it was investigated how high the protection against the Corona variant Omikron turns out if vaccinated persons who received either Biontech or Coronavac as a first and second vaccination were then vaccinated again with one of the two alternatives as a booster.

The result was published by the University of Hong Kong.

Corona inactivated vaccine against Omikron: Study delivers sobering results

It turned out that people who had been vaccinated twice with the dead vaccine, who also received Coronavac as a booster, did not develop a sufficient number of antibodies against Omikron.

It was different with those who received the vaccine from Biontech / Pfizer as a booster.

Regardless of whether they had received the dead vaccine as a first or second vaccination, their antibodies together with the mRNA booster were at a sufficient level.

A health care worker in Colombia shows a dose of the corona vaccine CoronaVac.

© Secretaria Salud Bogota / dpa

In addition, the researchers found that neither a double vaccination with the dead vaccine Coronavac nor with Biontech / Pfizer produced sufficient antibodies against Omikron.

“All those who already have two cans of Comirnaty [from Biontech / Pfizer's note.

Red] or Coronavac should be given a third dose of Comirnaty vaccine six months after their second vaccination.

In this way you can develop optimal protection against the Omikron variant, ”emphasized Malik Peiris, one of the heads of the study.

(slo)