2 doses of Pfizer / BioNTech vaccine effective against mutations

gave | Friday, February 12, 2021 – 12:06 | Last Updated: 12 02 2021 – 12:06

Oxford University virology department in the UK found that people with 2 doses of Pfizer / BioNTech coronavirus vaccine had strong immunity to the original coronavirus, including the Kent and South African mutations of the virus. Based on the scientific research results, scientists announced that the vaccine continues to provide strong protection against mutated coronavirus.

British scientists tested the immune system against the mutated coronavirus in the first part of the study. It was found that although individuals’ antibody responses to the mutated virus were dulled, they may have high enough antibodies to protect most people from becoming infected after the second dose of vaccine. Antibodies from those vaccinated with two doses of the Pfizer / BioNTech vaccine were seen to recognize and inactivate viruses carrying some of the mutations in South Africa and Kent (the mutation common in the UK).

William James, a virology professor at the University of Oxford, and his colleagues collected blood samples from people recovering from coronavirus and healthcare professionals who had one or two doses of Pfizer / BioNTech vaccine. ‘Isolates’ of the B117 and B1.351 virus mutations, identified as Kent and South African mutations, and an older mutation similar to those circulating a year ago were obtained. Antibodies and T cells from individuals were then tested against these mutated viruses to see how well they performed.


The study found that the human antibodies were moderately effective against the original virus after the first dose of vaccine, less effective against the Kent variant, and unable to inactivate the South African variant. On the other hand, strong ‘T cell responses’ against all known variants were detected in the same individuals after the first vaccine. Scientists found that with the second dose of vaccine, people provided much stronger protection against mutations and the original virus.


“It may not necessarily protect you against infection (the first dose), but this first dose is very likely to make it much easier for your immune system to respond well next time,” Prof William James said of the results of their scientific study. “We think this is why the second dose produces such a strong antibody response, because the T cells are already there and ready to react.”


Professor James says, “It makes no promise that you won’t get sick from the new mutations, but it does show that there is something that will work and your immune system can respond to them. In more than 90 percent of cases, the antibodies people produce after the second dose have risen to the level we hope to neutralize the virus and protect them from infection. “We are pretty confident that they will be protected against South Africa and Kent mutation as well as the (original) species,” he said.