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Neutralising antibody levels induced by the Oxford-AstraZeneca vaccine against different SARS-CoV-2 variants

This article was published on
June 28, 2021

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A research letter published in The Lancet looks at Oxford-AstraZeneca vaccine-induced neutralising antibody activity against different SARS-CoV-2 variants.

A research letter published in The Lancet looks at Oxford-AstraZeneca vaccine-induced neutralising antibody activity against different SARS-CoV-2 variants.

Publication

AZD1222-induced neutralising antibody activity against SARS-CoV-2 Delta VOC

Not peer-reviewed
This work has not been scrutinised by independent experts, or the story does not contain research data to review (for example an opinion piece). If you are reporting on research that has yet to go through peer-review (eg. conference abstracts and preprints) be aware that the findings can change during the peer review process
Peer-reviewed
This work was reviewed and scrutinised by relevant independent experts.

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Expert Comments: 

Prof Jonathan Ball

This study shows that overall levels of antibodies that can prevent virus infection in the lab are greater following two doses of the Pfizer vaccine than with two doses of the AZ vaccine, and this is especially noticeable for some viral variants that are in circulation.

It isn’t clear if these lower antibody levels are due to differences in the vaccine delivery system – where AZ use a chimpanzee adenovirus and Pfizer uses mRNA – or in the form of the coronavirus spike protein used to raise immunity.

What this type of laboratory study doesn’t tell us is how well vaccine immunity is continuing to protect people from serious disease and death. There’s more to immunity than simply high levels of virus-killing antibodies, and it may well be that as far as protection against serious disease is concerned, there is still a lot of immunity left in the tank. So far, the evidence suggests that, in most people, the vaccines are continuing to perform well.

But that doesn’t mean we should be complacent. We should continue to monitor vaccine effectiveness, especially against existing and new variants that will undoubtedly arise in future.

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