MUTATED NOVEL CORONAVIRUS
Context
- A mutated variant of the novel coronavirus SARS-CoV2 has been associated with recent infections in England. The question being raised is whether the mutation could affect people’s response to vaccines.
- The virus has undergone several mutations since it first infected humans, which scientists say is neither unexpected nor a cause for panic.
More about news
- New mutation identified by UK researchers as N501Y. It is likely to be a mutation in the spike protein. There has been a single nucleotide change in one portion of the spike protein, so there would be no bearing on the disease biology or even diagnostics
Effect on Infection and Vaccination
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- Several coronavirus vaccines are designed to create antibodies targeting the spike protein.
- The vaccines target multiple regions on the spike, while a mutation refers to a change in a single point. If there is one mutation, it does not mean vaccines would not work.
- All SARS-CoV-2 strains are genetically similar to one another, and scientists do not expect these mutations to have a significant impact on their ability to cause more severe disease than what has been observed so far.
- Many mutations mean nothing at all, or at least are more successful for reasons not known. For instance a different strain may be more transmissible, but cause less disease.
- Researchers need to monitor the mutations as there is no evidence that the new strain in the UK is more transmissible or more severe/resistant to treatment or vaccination.
- Previous mutations of Covid-19 include D614G, which emerged in Europe in February, and the Spanish-originated A222V that emerged in summer but they all behaved the same way.
- Vaccines, in general, tend to target an early version of the virus.
- Usually, an older strain of a virus will preserve enough features that it will provide immunity against a whole group of variants.
- Our immune system has a terrible memory for flu viruses, noting that the immune response to the flu only lasts around a year before we need to get revaccinated. For example, for more than 45 years, we’ve had a very effective vaccine for measles, mumps, and rubella (which are also RNA viruses).
- These viruses have not mutated [enough] to escape the protection provided by the vaccines. The same could very well apply to COVID-19.