A small preliminary study carried out in South Africa suggests that the protection offered by the antibodies of a double dose of the Pfizer vaccine is considerably reduced but not canceled with the omicron variant and suggests that those infected earlier and vaccinated are more protected.
The study, based on the analysis of the effects of omicron on blood samples from 12 people previously vaccinated in South Africa with Pfizer-BioNTech’s anticovid solution, was carried out by specialists from the Africa Health Research Institute, AHRI) and released last night for peer review by the scientific community.
“Laboratory research from South Africa strongly suggests that the omicron variant of SARS-COV-2 escapes the antibody immunity induced by the Pfizer-BioNTech (Comirnaty) vaccine, but that people who were both vaccinated and previously infected retain considerable immunity,” noted AHRI (which is based in the city of Durban) in the presentation of the report.
The executive director of the institute, Willem Hanekom, pointed out that the “clinical implications” of these preliminary data have yet to be defined and specified that, although the most likely conclusion is that the existing formulas offer less protection against omicron, “vaccinologists agree that current vaccines still protect against serious illness and death. “
While these data cannot be directly equated in terms of vaccine efficacy, the observed drop in antibody protection is 41 times greater for the omicron variant than for the parent coronavirus.
One of the study authors, researcher Alex Sigal, later specified through social networks that the data from this study are “better” than was initially expected for omicron, given its multiple mutations.
“Based on the genome, I thought it would be worse. It seems that it is mostly a question of quantity, the more antibodies the better,” Sigal noted on Twitter in conversation with other scientists.
Other specialists also pointed out that, since the blood of people with the double dose who had also suffered a previous omicron infection was mostly neutralized, a third booster dose could be the key to combat this variant.
The study, however, does not include information regarding samples with third doses because at the moment they are not being applied in South Africa (which has only about 25% of its population vaccinated).
In addition, scientists consider that antibodies are not the only response tool against the virus provided by vaccines, since, for example, they also stimulate “memory” B and T lymphocytes that would remember how to fight that virus in the future.
The chief executive of the pharmaceutical company Pfizer, Albert Bourla, said Tuesday at a forum organized by The Wall Street Journal in New York that the symptoms caused by the coronavirus omicron seem milder, but he warned that the variant is transmitted faster.
Bourla noted that his company is investigating the protection of its vaccines against this variant and assured that he hopes to have more information in the coming weeks, but did not offer a specific date.