On Wednesday, April 28, the World Health Organisation (WHO) said that the Indian Strain of the Coronavirus has been detected in 17 countries. The Indian Strain, which is contributing to the surge of COVID-19 cases in India, is also known as the B.1.617 variant of SARS-CoV-2 or double mutant. The UN health body said that the Indian Strain has been found in over 1,200 sequences uploaded to the GISAID database. GISAID is a global science initiative and primary source established in 2008 that provides open access to genomic data of influenza viruses and the coronavirus responsible for the COVID-19 pandemic.
The WHO has also described it as a "variant of interest", suggesting it may have mutations that would make the virus more transmissible, cause more severe disease or evade vaccine immunity.
“Preliminary modelling by WHO based on sequences submitted to GISAID suggest that B.1.617 has a higher growth rate than other circulating variants in India, suggesting potential increased transmissibility, with other co-circulating variants also demonstrating increased transmissibility,” the report by the global health body said.
In 2021, we have heard about many variants of SARS-Cov-2 that have created havoc in many parts of the world. In India, particularly, apart from reckless behaviour against the COVID-19 protocols, experts believe that the second wave of Coronavirus in India was also propelled by the double mutant strain. Double mutant is considered to be slightly more transmissible but scientists are still trying to study the Indian Strain which has raised global concern. Here is what we know so far:
What is B.1.617?
The double mutant is called B.1.617 in scientific terms and is one of the variants of SARS-CoV-2 that causes COVID-19. It is called double mutant because of two key mutations on the spike of the virus - L452R and E484Q.
The L452R mutation has been found in fast-spreading variants in California (B.1.427 and B.1.429). This mutation was first detected in Denmark in March and was later found to be widespread in California. It can increase the binding power of spike proteins with ACE2 receptors on human cells, making it more transmissible. L452R can also potentially enhance viral replication.
The E484Q mutation has been found in multiple other variants as well, including the UK (lineage B.1.1.7) variant and South African (B.1.351) variants of the Coronavirus. It can slip past the immune response and have much greater binding and antibody escape capabilities.
When was it first detected?
According to Indian SARS-CoV-2 Genomics Consortium (INSACOG), the consortium of laboratories that are sequencing a sample of genomes from coronavirus patients in India, B.1.617 was first detected in India on December 7, 2020, in Maharashtra. Later, 361 samples taken from January to March by Pune’s National Institute of Virology found 61 per cent or 220 samples in Maharashtra to be of double mutation. Maharashtra is one of the worst-affected states in the country and accounts for lion's share of coronavirus cases in India.
In March, the Union health ministry formally acknowledged the presence of double mutant in India and said it was detected in Delhi, Maharashtra, Punjab and some other places.
Is this variant more dangerous?
The two mutations have been seen separately where they have characterised as highly infectious and transmissible but together these mutations can evade antibodies and can be far more infectious. This double mutation also carries two different spike protein markers which makes it more efficient in attaching with the human host cells and multiplying faster.
Anurag Agrawal, the Director of the Institute of Genomics and Integrative Biology (IGIB), told PTI, “As far as we know, neither the UK variant nor B.1.617 is associated with increased severity of illness or death. The UK strain is proven to have higher transmissibility and B.1.617 may have increased transmissibility."
"But B.1.617 variant has more transmissibility is not been proven and there are several characterises to prove it and the studies have not been completed. But looking at Maharashtra's experience, it looks more transmissible, but it is yet to be proven,” he added.
Nithya Balasubramanian, the head of healthcare research at Bernstein India, told Bloomberg TV, “We did the math and we do believe that a lot of the increase in the reproduction number can be explained by these mutations. So, yes, the mutations are a big cause for worry."
William Haseltine, a former professor at Harvard Medical School wrote in Forbes on April 12, “The B.1.617 variant has all the hallmarks of a very dangerous virus. We must do all that is possible to identify its spread and to contain it."
Jeffery Barrett, director of the COVID-19 Genomics Initiative at the Wellcome Sanger Institute in the UK, tweeted that the Indian variant has spread at such low levels over the past few months, and that makes it "likely not to be as transmissible as B.1.1.7".
Although many health experts claim that the B.1.617 variant spreads faster and is more infectious but there is no scientific evidence to prove it.
“While the UK variant is proven to have a higher transmissibility, with the India strain, there is only scepticism so far,” said Anurag Agrawal.
Is the vaccine effective against B.1.617?
Amidst all the gloom, one ray of hope is that the two Coronavirus vaccines currently in use in India - Covishield and Covaxin – have efficacy against the double mutant.
Anurag Agrawal has said that the study on the effectiveness of the available vaccines on the B.1.617 variant suggests that post-vaccination, the infections are milder.
Another study by the Centre for Cellular and Molecular Biology (CCMB) in Hyderabad under the CSIR suggests that early results using in-vitro neutralisation assay show that both convalescent (prior infection) sera and Covishield-vaccinated sera offer protection against the B.1.617 variant.
White House chief medical adviser and America's top pandemic expert Dr Anthony Fauci on Tuesday, April 27, claimed that India’s home-grown COVID-19 vaccine – Covaxin - is found to be effective against the Indian double mutant strain.
"The most recent data was looking at convalescent Sera of COVID-19 cases and people who received the vaccine used in India, the Covaxin. It was found to neutralise the 617 variants,” said Dr Anthony Fauci.
Although it remains unclear whether the Indian variant is responsible for the increase in infections in India but it bodes well for the world that both vaccines are indeed effective against the Indian strain. Despite being home to the world's largest vaccine manufacturer, India has fully vaccinated less than 2 per cent of its 1.3 billion-strong population. The sooner the vaccination picks up in the country, the better protection it will be able to build up against double mutant variant.