Supriya Yadav, Microbiologist at Vital Neutraceuticals Pvt. Ltd.
In India, Covid-19 transmission is exploding at an unseen rate and the second wave has been more terrible than the first wave in every way. The country has reported an unexpected hike of new cases daily and death rates are mounting too every hour. Amid this, a new variant of the virus causing Covid-19 has been detected in West Bengal. The triple mutant variant’(also being referred to as the 'Bengal strain' of Covid-19) is reportedly more infectious than other strains. Well, previously Indian researchers had discovered the Indian variant i.e.,'double mutant variant' of the virus back in October last year.
Key Highlights
- In Maharashtra, over 60% of all coronavirus infections have been linked to the new B.1.617 variant, based on the infections that have been sequenced for their origin.
- Mutations play a role but as only 15% of those infected carry the B.1.618-triple mutant variant, it cannot alone explain the hike of cases.
- In Maharashtra, where the double mutant variant has been detected, about 80% samples have been of other variants.
All viruses naturally mutate over time, and Sars-CoV-2 is no exception. Since the virus was first identified a year ago, thousands of mutations have arisen, most notably the “Double and Triple mutant variant”. In this article, we review why these variants cause so much buzz to scientists, public health organizations, and the public at large and what we know so far about these variants. Below, we explore what viral mutations are, how they relate to the development of new viral strains, and whether the new SARS-CoV-2 variant identified is a cause for concern.
Here are 5 Things you should know about Covid-19 mutant Variants:
- What do you mean by the mutation of a virus?
- What is “Double Mutant Variant”?
- What is “Triple Mutant Variant”?
- How effective is the vaccine to new variants of the virus?
- How can we prevent future new variants of the COVID-19 virus?
Mutation is change in structure of a gene caused by the alteration of single base units in DNA, or the deletion, insertion, or rearrangement of larger sections of genes. Viruses mutate all the time, as part of evolutionary biology. Some mutations weaken the virus while others may make it stronger, enabling it to proliferate faster or cause more infections.
The double mutant Covid-19 variant was detected in samples collected from Maharashtra back in October last year. A double mutant variant of a virus is not a rare occurrence even if it’s not very common. Viruses evolve to sustain their lives and improve infectivity. However, in India's case, the double mutant variant, scientifically known as B.1.617 consists of two mutations on the spike protein (viz. L452R and E484Q) of the virus. A spike protein helps a virus to enter the body and infect it. This virus has been detected in a few samples, which is said to be more effective and lethal. In Maharashtra, over 60% of all coronavirus infections have been linked to the new B.1.617 variant, based on the infections that have been sequenced for their origin.
The scientists say that the virus has mutated further and has three types of mutations – hence the name triple mutant Variant, scientifically known as B.1.618. The triple mutant Variant was found to be mostly circulating in West Bengal. Research is being done to understand the link between triple mutant and the new surge in viral infections. It is of importance to know that this mutant is not only highly transmissible but it may also escape any sort of immune barrier. Mutations play a role but as only 15% of those infected carry the B.1.618-triple mutant variant, it cannot alone explain the hike of cases.
In Maharashtra, where the double mutant variant has been detected, about 80% samples have been of other variants. Vaccines are a critical tool for fighting the battle against COVID-19. Moreover, scientists are investigating to understand the repercussions for vaccines, which are based on the spike protein sequence. Meanwhile, most of us believe that the existing vaccines are likely to work to some extent to reduce infection/transmission rates and severe disease. We must proceed with vaccination even if the vaccines may be somewhat less effective against some of the COVID-19 virus variants. We are all safe only if everyone is safe.
As more people get vaccinated, virus circulation will decrease, which will lead to fewer mutations. Priority should be given to vaccinating high-risk groups everywhere to maximize global protection against new variants and minimize the risk of transmission. The best ways of protecting people before more people get exposed to the virus and the risk to new variants: more manufacturing of vaccines to the large scale and rolling out vaccines as quickly and widely as possible.
Conclusion
Current measures to reduce transmission – including frequent hand washing, wearing a mask, physical distancing, good ventilation and avoiding crowded places or closed settings – continue to work against new variants by reducing the amount of viral transmission and therefore also reducing opportunities for the virus to mutate. The problem is, the more variants we get, the greater the chance the virus will be able to escape part of the vaccine - and this may reduce its efficacy. In the short-term, only the harshest of lockdowns will reduce case numbers; only lockdown can reduce the number of people with the virus and from spreading.
