The discovery of a new mutant SARS-CoV2 virus in southern parts of England about 10 days ago led to growing alarm and poured cold water on some of the enthusiasm that emanated from the advent of a bunch of Covid-19 vaccines and, for Indians, from the fact that the active cases have started coming down steadily over the last many weeks.
The variant, seen to be 70 per cent more contagious than earlier strains of coronavirus causing Covid-19 in initial studies, has forced the UK government to go for tighter restrictions across the country and has prompted as many as 40 countries to ban travel from the UK.
Mutation, or change, is an adaptive mechanism of viruses, a survival strategy of sorts. Viruses always try to mutate to stay relevant. Such mutations arise when the virus replicates. More importantly, it was one of the many mutations that SARS-CoV2 has undergone since it was first discovered in China last year.
What is there, then, to be worried about?
This particular variant seems to be genetically distinct from previously circulating variants of SARS-CoV. This has the propensity to transmit more with a slew of mutations in the spike protein which the virus uses to latch on to an enzyme present on human lung cells. However, there is no indication at this point in time the new variant is associated with increased infection severity. Moreover, it has emerged at a time when things were getting a little relaxed on account of reporting of lesser number of fresh cases and expected arrival of a few Covid-19 vaccines.
What measures are being taken to ensure that the new mutation does not lead to a spike in cases?
A number of countries, including India, have temporarily severed travel links with the UK. No flights are allowed to come to India from the UK till December 31 and the situation will be reviewed later to see if the travel ban needs further extension. For the last two days, RT-PCR tests have been made compulsory for those who travel from or transit through the UK and have Covid-19 like symptoms.
The Central government also issued a new standard operating procedure, wherein the government will conduct genome sequencing of all Covid positive passengers arriving from the UK between December 21 and 23 to determine whether they have been infected by the new strain of the virus found there.
It has also asked States and the Integrated Disease Surveillance Programme to step up monitoring of travellers from the UK who arrived in India from November 25 to December 8. Genome sequencing will be done on the virus found in all the positive patients. If it is found to be of the new variant, the patients would be isolated.
Will the new mutation render Covid-19 vaccines being developed ineffective?
No. Most experts doubt that it will have any major impact on vaccines, even though it’s not possible to rule out any effect. Vaccines typically activate our immune system to produce a range of antibodies against a single viral protein, making it less likely that viruses can easily escape their attack, concur experts.
However, one worry is that the mutations that the new mutant has accumulated are in the spike protein which the virus uses to get attached to the lung cells. So, it is technically possible for a mutation to a coronavirus to change the shape of its spike protein, making it harder for the antibodies to get a tight grip on them.
But experts observe that at some point in time one particular mutation can make the current crop of vaccines ineffective. Already many flu vaccines undergo such ‘vaccine matching’, the process of modifying flu vaccines to combat new viral strains that are in circulation in each season. The time may not be here for SARS-CoV2 yet. Probably.
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