The second wave of Covid-19 cases in India has risen faster than the first wave. Many experts are of the view that this is because the mutated variants of novel coronavirus are more infectious and transmissible.

A mutation is not rare, as viruses mutate all the time.

While some mutations weaken the virus, others may make it stronger, enabling it to transmit faster or cause more infections.

Since the beginning of the pandemic, there are thousands of different versions or variants of SARS-CoV-2 circulating in the world.

But only a few of them managed to grab the attention of scientists for being more infectious, easily transmissible or lethal.

Mutated Virus

The concerning variants identified so far are informally associated with the name of the county where scientists first found them.

These are; the B.1.1.7 UK variant, the P1 Brazil Variant, the B.1.351South Africa Variant and the double-mutant, which combined mutations from two separate virus variants--E484Q and L452R.

India, which is the second most-affected country after the United States, has reported several Covid-19 cases linked to coronavirus variants from the United Kingdom, South Africa and Brazil.

According to research findings, some of these variants are found to be concentrated in specific regions in India.

According to a study by NIMHANS that was published in medRxiv, researchers had sequenced genomes from 73 international travellers arriving in Karnataka and 103 local Covid cases in Bengaluru. The study revealed that the UK variant was the major lineage imported into the state, detected in 32.9 per cent of samples processed. But experts did not detect variants from Brazil and South Africa.

NIMHANS researchers found another variant dubbed B.1.36 in 27.4 per cent of the ‘imported’ samples. This variant was first identified in Saudi Arabia in February 2020.

In terms of the UK variant, the Union Health Minister Dr Harsh Vardhan said on 6 April that 80 per cent of Punjab’s coronavirus cases have the UK variant.

Experts in India found the "double mutant" variant in more than 60 per cent of cases sampled for genome sequencing in Maharashtra.

On 21 April, Vinod Scaria, a scientist at the Council of Scientific and Industrial Research’s Institute of Genomic and Integrative Biology (CSIR-IGIB) said on Twitter that a new mutant coronavirus with a distinct set of genetic and immune escape variants has been detected by scientists.

As per the finding, the initial sequences of the new variant were found in West Bengal.

How Concerning Are These Variants?

In terms of risk factors, the New York Times reported in March that British scientists warned that the B.1.1.7 UK variant is contagious enough that new control measures, including closing down schools and universities, might be required, along with the acceleration of vaccine rollout.

The experts estimated that the UK variant was 56 per cent more contagious, while the UK government released an initial estimate of 70 per cent.

However, the study by British researchers found no evidence to claim that it is more deadly than other variants.

Another study published in the journal Nature suggested that the risk of dying from this version of the virus at the 28-day mark is 61 per cent more than if infected with other strains.

A Reuters report revealed that as per new data, the P1 Brazil variant is likely able to reinfect people who survived infections with earlier versions of the virus.

Scientists also found that this variant is more contagious than the initial strain of the novel coronavirus.

It includes a mutation known as E484K, which is also present in the South African variant.

E484K is also called an "escape mutation" as it helps the virus dodge the antibodies.

The South African variant includes another mutation, called N501Y, which appears to make it more contagious or easy to spread.

In terms of B.1.617 “double mutant”, it has been found in countries like Australia, Belgium, Germany, New Zealand, the United Kingdom and the United States.

Dr Aparna Mukherjee, senior scientist at the Indian Council of Medical Research (ICMR), told News18 that this variant can “theoretically be responsible” for increased transmissibility and possible immune escape.

But unlike other variants, this one is still under investigation and has not yet labelled as a "variant of concern".

She suggested that during this current scenario genome sequencing will help to know how the virus is changing and whether any particular measures are required in terms of prevention and control.

However, amid all the rising concerns related to all the variants, an ICMR study found that Bharat Biotech's Covid-19 vaccine Covaxin neutralises against multiple variants and effectively neutralises the double mutant virus as well.

Even earlier Y.K. Gupta, former Dean and Head of Pharmacology AIIMS, Delhi and current president of AIIMS - Bhopal and AIIMS-Jammu also told Business Standard that Covaxin and Serum Institute's Covishield will be effective against all the variants found so far.