How new mutations affect the coronavirus?
Mutations are a common occurrence in most viruses. As a virus replicates inside a host, random errors while copying its genetic code can lead to mutations. Much of the time, these mistakes can be harmless or make a virus weaker. But occasionally, these mutations can help the virus to thrive, giving rise to new variants, which people are referring to as strains. Just as evolution would have it, those variants with the most adaptive features will be the ones that survive and multiply, which can lead to multiple variants of a given virus within a population.
Once a successful new variant emerges, there could be a number of potential consequences. The mutations could help the virus’s ability to infect the host and spread from person to person. They could also change the severity of the disease after infection, or make the virus harder to detect by existing diagnostic tests. In addition, mutations could enable that variant of the virus to be protected against antiviral medicines or vaccines.
Many COVID-19 variants are circulating throughout the world, such as those identified in South Africa and Brazil. One of the most notable variants emerged from the United Kingdom and has quickly spread across continents. Known as B.1.1.7, this variant has an unusually large number of mutations, with many of them in the spike protein, which the virus uses to attach to and infect host cells.
Research suggests that the new variant is associated with increased transmission, meaning the virus could be more contagious. Scientists are still studying the variant's severity for those infected, and the impact of the mutations on vaccine efficacy is still to be fully determined. This continued “strain surveillance” is critical for monitoring the course of a pandemic over time and determining the most effective public health response.