The coronavirus genome has mutated hundreds of times since last December, however most mutations have had very little to no effect (called silent mutations) at all on reproduction and mortality rate. Recently, variants involving changes to the spike protein have emerged from South Africa (501Y.V2), the UK (B117) and Brazil (P.1). All of the variant strains have the genome mutation N501Y which makes them more contagious as well as the mutation E484K which causes a change in the spike protein. In Canada some cases of the UK variant have been found due to community spread, and it is predicted that the variant will completely replace the original coronavirus strain by March 2021 due to it being over 50% more contagious. It was shown that people who contracted the new UK strain were more likely to have to have symptoms of fever, fatigue/ weakness as well as a cough. For the UK virus strain it is also predicted that the number of deaths of people in their 60s could rise from 10 per 1 000 to 13/14 per thousand people.
People can contract the new variant after having had the original coronavirus strain, as the memory B cells in the immune system are unable to recognize the new spike protein. The vaccine may provide some immunity as the variant strains have mutated a certain part of the spike protein and antibodies developed by the vaccine will be able to recognize the rest of the spike protein that was not mutated. It’s thought that people who contract the new strain after being given the vaccine will have a milder case of the virus. Currently in Canada, the UK variant is in the process of taking over other strains as over half of new cases are of that variant. There is also concern over the new variant ‘The Indian variant’ (B.1.617) and has been found here in Ottawa.
References:
https://www.youtube.com/watch?v=Djy3WNLz_mM&t=29s
“What Are Covid Variants – and
Should We Be Worried?” The Guardian, Guardian News and Media, 5 Feb.
2021, www.theguardian.com/world/2021/feb/05/what-are-covid-variants-and-should-we-be-worried
Mahase, Elisabeth. “Covid-19: What
New Variants Are Emerging and How Are They Being Investigated?” The BMJ,
British Medical Journal Publishing Group, 18 Jan. 2021, www.bmj.com/content/372/bmj.n158.full
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