As of: December 8th, 2021 11:59 a.m.
A first study shows that current corona vaccines have a much weaker effect against the new Omikron variant. According to virologist Ciesek, the data say nothing about whether vaccinated people are protected from a severe course.
According to the virologist Sandra Ciesek, the first laboratory tests on the effect of corona vaccines against Omikron indicate a weaker defense reaction. The scientist from the University Hospital Frankfurt published the first results on Twitter, which show a significantly reduced antibody response to the new variant.
“The data confirm that the development of a vaccine adapted to Omikron makes sense,” wrote Ciesek. South African experts had already presented similar data the day before, according to which the antibody response in people vaccinated against Omikron is weaker.
Immune response reduced 37 times
However, Ciesek also pointed out that it is not possible to read from their evaluation whether vaccinated people are protected from a severe course at Omikron. Because the immune response is not only based on antibodies, but also, for example, on T cells.
According to Ciesek, the antibody response to Omikron is up to 37 times reduced compared to the Delta variant – there is also a reduction in people with a booster vaccination. The data have not yet been reviewed by specialist colleagues and have not been published in a specialist magazine.
Drosten: “Third dose required”
The virologist Christian Drosten praised Ciesek’s survey as “important data” and again emphasized the need for a booster vaccination. “Doesn’t look good for someone who was vaccinated twice. Third dose required,” wrote Drosten on Twitter.
In order to examine the effect of a vaccine against a certain variant of SARS-CoV-2, researchers usually do so-called neutralization tests. It is checked how many antibodies a vaccinated person has in the blood that can bind to the virus variant and thus switch it off. The actual protection of vaccinated persons cannot be determined with this, however, clinical studies with thousands of test persons or evaluations of the ongoing infection process are required.
African study with similar results
Researchers at the Africa Health Research Institute in South Africa published preliminary data on Tuesday on the effectiveness of the BioNTech / Pfizer vaccine against Omikron. According to a communication, the results suggest that the virus variant escapes the antibody response of two-fold vaccinees. In vaccinated persons who were also infected, however, a considerable antibody response was measurable. These results have not yet been published in a specialist journal either.