If this new version of the virus is here to stay, as it appears to be, what does that mean? Will this new version of the virus replace the old one? Will it be easier to catch? And, most important, will the current vaccines still be effective?
Eight of these 23 mutations affect the spike protein. This matters because the spike protein enables the virus to enter human cells, and it is a key target of our immune response, both in fighting off the virus during infection and in protecting us from disease following vaccination with the Pfizer and Moderna vaccines.
If the changes to the spike protein help the virus enter human cells more easily, then the virus could be transmitted from person to person more readily.
These mutations may also alter how well the host’s immune system combats the virus, potentially reducing the efficacy of the current vaccines.
The increase in frequency is concerning, as it suggests — but does not prove — that the B.1.1.7 isolates of SARS-CoV-2 are more transmissible than the original virus. Some have estimated that the new virus may be up to 70% more transmissible than the old virus. While these estimates are consistent with the data, it is entirely too early to make a definitive conclusion.
If this increase in transmissibility is confirmed, it might be due to of the mutations in the spike protein allows it to bind more tightly to the ACE2 receptor, which provides a gateway for the virus to enter human cells.
But it might also be due to any of the other changes to the virus.
If the new version, B.1.1.7, is indeed more transmissible than the old virus, it will be more dangerous in the sense that it will make more people sick.
Vaccine-virus mismatch is an ongoing challenge for scientists charged with developing the seasonal flu vaccine. But even with a virus-vaccine mismatch, the flu vaccine reduces the likelihood, and the severity, of disease.
The question is therefore not whether the vaccines will be effective, but rather how effective they will be. The severity of the mismatch matters, but the only way to determine its impact in this case is through scientific study, and to my knowledge, no data on that has yet been collected. In other words, it’s too early to say whether and how this new variant will influence the overall effectiveness of the Pfizer and Moderna vaccines.
The appearance of this new B.1.1.7 makes it even more important that people get vaccinated as soon as possible.
If this new version is more transmissible, or if the vaccine is less effective because of a virus-vaccine mismatch, more people will need to be vaccinated to achieve herd immunity and get this disease under control.
David Kennedy is an assistant professor of biology at Pennsylvania State University. This article is republished from The Conversation under a Creative Commons license.
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