Will Vaccines Work Against New Mutations?
Here’s what the science says
Elemental published an extremely thorough guide to the Covid-19 vaccine, answering every possible question. The FAQ is being updated and added to as the vaccine process continues. Here’s one of the newest questions.
Q: Will the current vaccines protect against the new Covid strains scientists have discovered?
In recent weeks, much Covid reporting has focused on two new variants of the SARS-CoV-2 coronavirus: one, called B.1.1.7, appears to have originated in the United Kingdom and the other, 501Y.V2, in South Africa. Though a study last August concluded that Covid vaccine candidates “would likely match all currently circulating variants,” the big question now is whether the two authorized vaccines, or any vaccines currently in trials, will protect against these brand new variants.
The South African variant raises more concerns than the UK one because of where its mutations occur. In mid-December, vaccine manufacturers had already begun studying whether their vaccines would work on the new variants. Scientists don’t have a firm answer, yet but the most recent data suggests some optimism. A small study by Pfizer and scientists at the University of Texas Medical Branch showed that the Pfizer vaccine seems to work against both new variants. However, the study is small and not yet peer-reviewed. Moderna has not yet published any data about the new variants and its vaccine.
It’s important to note that these kinds of mutations were not unexpected. All viruses mutate, the coronavirus has already mutated thousands of times, and scientists, including vaccine developers, expect it to continue mutating. What matters is how much it mutates and where those mutations occur. Current vaccines target the spike protein, which has already accumulated about 4000 mutations. These haven’t affected the vaccine’s effectiveness because current vaccines target multiple parts of the spike protein. It would take major changes to affect how well the vaccine works, and those are unlikely to happen soon, as University of Texas Medical Branch researcher Vineet Menachery told Vox.
Further, even if the mutations do affect current vaccines’ effectiveness, it doesn’t mean the vaccine would suddenly become useless. It may become less than 95% effective, but it would still offer some protection. If the coronavirus ever mutates so much that the vaccine becomes very ineffective, it wouldn’t require a whole other year to develop a new vaccine either. Since the Pfizer and Moderna vaccines use an mRNA platform, all they need to do to tweak the vaccine is swap out the genetic code so that it instructs cells to create a spike protein like those on the new variants. The downside is that it might mean another round of vaccinations, but for now, that still appears to be a problem in the future, not the present. We’ll update this question as we learn more.