Virus Mutation: New SARS-CoV-2 strain

SCIENCE & TECH/ HEALTH/ GOVERNANCE/

Topic: General Studies 2, 3:

• Government policies and interventions for development in various sectors and issues arising out of their design and implementation.
• Science and Technology- developments and their applications and effects in everyday life. 

Virus Mutation: New SARS-CoV-2 strain

Context: A year after the novel coronavirus announced itself in China, there was yet another critical update in December 2020 — the emergence of a new strain of the virus, caused by mutations, that seemed to be 70% more transmissible.

Mutations were reported from different parts of the world, including Denmark, Australia, England and South Africa, but the rapid domination of the new strain — lineage B 1.1.7 — in the south of England set off a chain of events, including curbs on travel and Christmas celebrations.

What is the WHO saying?

• WHO Chief cited a basic fact of virology, that viruses mutate over time and it is natural and is to be expected. 
• Trying to counter many ill-informed discussions triggered by panic from the usage of the word ‘mutation’, WHO Chief said the U.K. had reported that the transmission was higher, but there was no evidence that it causes a more severe disease. 
• He also added that ongoing studies will clear the air on this angle.

Why do viruses mutate?

• Mutation is part of the life cycle of a virus. 
• Once the virus latches on to a host, it begins to replicate and make copies of itself. 
• During the process of virus replication, random errors arise, one or two protein molecules change, possibly induced by the immune response mounted within infected people.
• These changes in the genomic structure of the virus can be considered mutations. Not all mutations are significant, but those that affect the virus’s ability to survive or replicate are important.

How was the new strain identified?

• The English variant was identified in genomic surveillance by COVID-19 Genomics UK (COG-UK), a consortium that analyses genome sequencing data from the U.K.
• The variant is the result of multiple mutations in the spike protein (the point of viral entry into the host) of SARS-CoV-2, as well as mutations in other genomic regions of the RNA virus.
• COG-UK reportedly identified one of these mutations as ‘N501Y’, in an area of the spike protein that binds to a key protein in the human cell, the ACE2 receptor. This was an indication that the alterations may, theoretically, result in the virus becoming more infectious.
• As of December 13, according to Public Health England (PHE), there were 1,108 cases of the variant identified “predominantly in the South and East of England”. 
• The U.K. government’s website explains that backwards tracing using genetic evidence suggests this variant emerged in September 2020 and then circulated at very low levels in the population until mid-November.
• The increase in cases linked to the new variant first came to light in late November when PHE was investigating why infection rates in Kent were not falling despite national restrictions. 
• They then discovered a cluster linked to this variant that was spreading rapidly into London and Essex.

Can it be detected through PCR tests?

• The PCR test is used to identify a number of gene targets and will pick up this variant too. 
• The U.K.’s Chief Medical Officer has said that current swab tests are able to identify the new variant.

Is it known how a vaccine will react?

• Various studies are on to determine the impact of the vaccine on severity of disease or mortality. Also, scientists are working to know about the implication of mutated viruses for the vaccine that has already been developed.
• Scientists advocate for continuation of vaccination drives already started in many countries like UK, US and Russia. This is because vaccines will offer protection even from a mutant virus. 
• By their very nature, vaccines will make a variety of different antibodies and memory cells that will help fight off the infection
• Vaccines will reduce the number of people who get infected, reduce the number of people spreading the infections, lower the number of hosts, lower the chances of further mutations, and allows to get things under control

How can you protect yourself?

Simply by following the original advice on COVID-19 hygiene. Using a face mask, regularly washing hands, and maintaining distance with others when in a public setting will continue to be the best practical ways to prevent the infection.