The South African variant, of SARS-CoV-2, the virus responsible for COVID-19, may be better at evading the immune response created by the Pfizer-BioNTech vaccine, according to a yet-to-be peer-reviewed "real-world" study in Israel.
The study, available to read as a preprint, is currently under review and was conducted by Tel Aviv University and Clalit Health Services, Israel's largest healthcare provider. Israel is well-placed to carry out a real-world study on COVID-19 vaccines because over half the population have been vaccinated with both doses, including 80 percent of adults, with most having the Pfizer/BioNTech jab.
The study compared 400 unvaccinated people with 400 either partially or fully vaccinated. Among the fully vaccinated (150 people), the team found 8 cases where the patients developed COVID-19 due to the South African variant of the virus.
According to the study, the South African variant accounted for less than 1 percent of COVID cases in Israel. However, the incidence of this variant is about eight times higher than in those unvaccinated, indicating that this version of the virus can’t be countered as effectively by the Pfizer/BioNTech vaccine compared to other strains, including the UK variant, which is now the most prevalent variant in Israel.
“We found a disproportionately higher rate of the South African variant among people vaccinated with a second dose, compared to the unvaccinated group. This means that the South African variant is able, to some extent, to break through the vaccine’s protection,” Tel Aviv University’s Adi Stern told Reuters.
This is the first real-world study on whether the South African variant can bypass the vaccine, but the pharmaceutical companies behind the Pfizer and Moderna vaccines reported a reduction in the virus-neutralizing potential of the vaccine-induced antibodies against this variant in February, published in The New England Journal of Medicine.
The good news is that it doesn’t eliminate the potential completely, so it's possible severe cases of COVID-19 are still curbed by the vaccine even in the case of the South African variant.
While the results may appear concerning, the researchers cautioned that their sample size was small as the variant is not common in Israel, perhaps being "blocked" by the UK variant. Their study also wasn't designed to look at overall vaccine effectiveness against any variant, as it only looked at people who had already tested positive for COVID-19, and the vaccine is still highly effective.
[H/T: AFP via MedicalXpress]