Coronavirus: The Delta variant has become the dominant strain in the UK.New Delhi:
As the pandemic's first wave subsided towards the end of last year, it led to a sense of casual relief. But it did not last as the second wave hit soon with much more fury. This wave was blamed primarily on mutation in coronavirus, which fuelled a talk about its variants. The most worrisome of these mutants of SARS-CoV-2 is the Delta variant, now spreading to several countries.
However, mutation in coronavirus is not a unique phenomenon. Viruses mutate all the time and most of them are deemed non-dangerous.
The Delta variant, first reported in India in October last year, has already become the dominant strain in the UK and is moving in that direction in the US and a few other countries. Authorities in India have reported a further mutation in Delta, which has been identified as Delta Plus. But it is not yet clear how virulent or lethal it could be.
Dr Randeep Guleria, the director of All India Institute of Medical Sciences (AIIMS), Delhi, said there is not much data on the Delta Plus variant to suggest that it was more infectious or caused a higher rate of mortality.
Why Is Coronavirus Mutating?
The more a virus spreads in a population, the more is it likely to undergo changes. When a virus replicates itself, it may change its properties. Depending on where these changes are located in the virus's genetic material, they may affect its transmission or severity. This could also lead to a change in the symptoms it can cause. Some changes can even cause it to weaken the virus.
What Are Variants?
There could be multiple variants of SARS-CoV-2 circulating in the world since the pandemic's outbreak in Wuhan in 2019. According to a World Health Organization (WHO) report, those with the most potential to cause harm are called “variants of concern” and monitored closely by health officials.
Recently, the WHO also proposed using labels consisting of the Greek Alphabet - Alpha, Beta, Gamma, Delta, etc - to name the variants. This would help people - the non-scientific community - in differentiating and discussing the variants.
Here Are The "Variants Of Concern" Listed By The WHO:
Delta variant (B.1.617.2): One of the most virulent, this variant caused a lot of trouble in India during the second wave. Researchers say this variant transmits at double the speed of Alpha. This variant forced new lockdowns in several countries, including in Australia and Bangladesh.
A few days ago, White House Chief Medical Advisor Dr Anthony Fauci said that the Delta variant, which now makes up more than 20 per cent of all new cases in the US, could be the “greatest threat” to US attempt to defeat the pandemic.
However, WHO Chief Scientist Dr Soumya Swaminathan told NDTV on Thursday that the Delta Plus variant- a new mutant version of the Delta strain first detected in India - was not presently a “variant of concern” and its infection numbers were still low.
Kent or Alpha variant (B.1.1.7): First reported in the UK in September 2020, this variant has spread to at least 170 countries and could be mutating further, according to WHO.
Beta variant (B.1.351): This was first reported in South Africa in August 2020. Since then, it has overwhelmed the country's health system and has now spread to 120 countries.
Gamma variant (P.1): It was first reported in north-western Brazil in December 2020. It has affected at least 70 countries.
These apart, there are a few other variants that have not shown any dramatic motive to spread or impact healthcare response. Some of these are Epsilon (US, March-2020) and Zeta (Brazil, April-2020).
What Do Scientists Know About The New Variants?
According to a report in the United States Centers for Disease Control and Prevention (CDC), viruses change through mutation, and new variants are expected to occur. “Sometimes new variants emerge and disappear. Other times, new variants persist,” states the CDC report. Scientists are studying these variants to learn more about them to find out if they “spread more easily from person-to-person, cause milder or more severe disease in people, are detected by currently available viral tests, respond to medicines currently being used to treat COVID-19, and change the effectiveness of COVID-19 vaccines”.
A report in The Lancet, dated June 28, 2021, states that the Delta variant has been causing “a sharp increase in COVID-19 cases in the UK”. The report adds that the daily hospital admissions and the number of patients requiring mechanical ventilation are now increasing in both England and Scotland, despite the ongoing roll-out of widespread vaccination in the UK.
How Effective Are Vaccines Against The Variants?
Since the Delta variant is reported to have the potential to infect partially vaccinated people, the focus of research globally is now to see how effective the vaccines already developed can be against it or whether it would require more doses.
A few days ago, the United States' National Institute of Health (NIH) said that Covaxin effectively neutralised both Alpha and Delta variants of coronavirus
About a week ago, the Central government said that both Covishield and Covaxin worked against Alpha, Beta, Gamma and Delta, variants, while effectiveness tests against the Delta Plus variant were ongoing.
When it comes to the third COVID-19 vaccine available in India - Sputnik V - according to its developers, is around 90 per cent effective against the Delta variant of coronavirus.
WHO expects the vaccines that are currently in development or have been approved should provide at least some protection against new virus variants. In a video titled, “What We Need To Know”, Kate O'Brien, WHO Director of the Department of Immunization, Vaccines and Biologicals, said that the situation was “dynamic” right now.
Watch the video here:
Ms O'Brien said, “But what I think we can say with pretty strong confidence is that we need to proceed as quickly as possible with vaccination.”