An early research report from a South African lab has offered some insight into how people vaccinated against COVID-19 might fare against the new Omicron variant.
The preliminary report of a study, which has not yet been peer-reviewed, carried out by the Africa Health Research Institute released earlier this week found that Omicron seems to have more capacity to evade vaccine-induced immunity.
However, it also stated that “Previous infection, followed by vaccination or booster is likely to increase the neutralisation level and likely confer protection from severe disease in Omicron infection.”
Dr. Alex Sigal, a virologist at the Africa Health Research Institute, said in an interview, “I expect boosters to restore better levels of protection. And, importantly, early clinical data from South Africa suggest that immunity — whether from vaccines or prior infections — is still effective in preventing the more severe forms of Covid-19.”
12 participants took part in this study. All of whom had been vaccinated with Pfizer. Half of them had previously been infected with SARS-CoV-2. The report notes it is not complete, particularly among those who have already contracted COVID-19.
On a separate note, Pfizer Inc. and BioNTech SE also reported earlier this week that a third or booster dose of their Pfizer vaccine neutralised the Omicron variant in lab tests but warned the two-dose regimen was significantly less effective at blocking the virus.
A third dose increased antibodies 25-fold compared with two doses against the Omicron variant, the companies said, according to the Wall St Journal. But two doses might still prove effective in preventing severe illness from COVID-19, because immune cells are able to recognise 80 per cent of parts of the spike protein that the vaccine targets.
“This is very positive news that should make everyone even more motivated to get vaccinated” and get a booster, said Pfizer Chief Scientific Officer Mikael Dolsten.
Pfizer’s chairman said the company started developing a version of its vaccine targeting Omicron last month, and that it could be available by March 2022. Moderna is on a similar path.
Information sources:
- https://www1.racgp.org.au/newsgp/clinical/first-omicron-studies-hint-at-enhanced-role-for-bo
- https://www.nytimes.com/live/2021/12/07/world/covid-omicron-vaccine
- https://www.nytimes.com/2021/12/08/briefing/omicron-pfizer-booster-scholz-germany-olympics.html
- https://www.wsj.com/articles/pfizer-biontech-covid-19-vaccine-loses-significant-effectiveness-against-omicron-in-early-study-companies-say-11638964121
