With India’s Covid-19 crisis deepening day by day and country’s health infrastructure left in shambles, reports now say that a triple mutation strain has been traced in parts of India. For the unversed, mutation is when the viruses keep changing and the more they spread, the more they mutate, which is what exactly happened in the case of India’s double mutant strain.
Two of these triple-mutant varieties have been found in samples collected from Maharashtra, Delhi, West Bengal and Chhattisgarh, and this might aggravate India’s Covid crisis further. On Wednesday, Vinod Scaria, a scientist at the Council of Scientific and Industrial Research’s Institute of Genomic and Integrative Biology (CSIR-IGIB) in New Delhi, rolled out a Twitter thread detailing the discovery of a new mutant coronavirus with a distinct set of genetic and immune escape variants. Initial sequences of the variant B.1.618 were found in West Bengal.
“It (the double mutant) was detected way back. It was found again in November and December. By February, this variant is exploding, almost coinciding with the surge in Maharashtra. The discovery should have been acted upon immediately. But nothing happened. Now we are fire-fighting,” reports mentioned.
What is a Mutant Strain?
In simple terms, just like all viruses, the coronavirus keeps changing as it passes from one person to another. The Covid-19 virus has been mutating ever since it emerged. During replication, a virus often undergoes genetic mutations that may create what are called variants. Variants with distinctly different physical characteristics may be co-termed a strain.
However, a lot of these mutations are not dangerous and don’t alter the way the virus behaves. Some mutations trigger changes in the spike protein that the virus uses to latch on to and enter human cells, a report by BBC said. A triple mutant refers to variants which have three different strains that have combined together to form a new variant. As of now, multiple SARS-CoV-2 variants are circulating globally and a triple mutant strain could be the next challenge for India.
Why is a mutant strain dangerous and needs effective monitoring?
These variants could potentially be more infectious, cause more severe disease or evade vaccines. As per CDC, here are some of the potential consequences of emerging variants:
- Transmissibility (Can spread more quickly in people): One mutation of the virus, namely D614G confers increased ability to spread more quickly than the SARS-CoV-2.In the laboratory, 614G variants propagate more quickly in human respiratory epithelial cells, outcompeting 614D viruses. There also is epidemiologic evidence that the 614G variant spreads more quickly than viruses without the mutation.
- Severity (Can cause either milder or more severe disease in people): Experts in the UK reported that B.1.1.7 variant may be associated with an increased risk of death compared to other variants.
- Ability to evade detection by specific viral diagnostic tests: Most commercial reverse-transcription polymerase chain reaction (RT-PCR)-based tests have multiple targets to detect the virus, such that even if a mutation impacts one of the targets, the other RT-PCR targets will still work.
- Potential impact on vaccination: These strains can evade the protection that immunizations are designed to generate. Both vaccination against and natural infection with SARS-CoV-2 produce a polyclonal response that targets several parts of the spike protein. The virus would likely need to accumulate multiple mutations in the spike protein to evade immunity induced by vaccines or by natural infection.
- Decreased susceptibility to therapeutic agents such as monoclonal antibodies.