Speculations are rife about whether the new mutant of the coronavirus has fueled the second wave of Covid-19 that is currently spreading rapidly in India.
In February, in it’s weekly epidemiological update, WHO said, “A variant can be labeled as “of concern” if it has been shown to be more contagious, more deadly or more resistant to current vaccines and treatments”.
The Indian Covid-19 variant officially known as B.1.617 was first found in India. It is the fourth variant that has been designated as “global concern” after Britain, South Africa, and Brazil.
Recently, the World Health Organization clarified that they have not associated the B.1.617 variant as the ‘Indian variant’. The organisation has urged to refer to the virus and its variants by their scientific names and not by the names of the countries in which they are first discovered.
On May 12, the agency’s South East Asia office tweeted, “WHO does not identify viruses or variants with names of countries they are first reported from. We refer to them by their scientific names and request all to do the same for consistency.”
What is B.1.617?
On May 12, the World Health Organisation declared B.1.617, a “variant of concern” from what they previously called it, a “variant of interest”. The specialized agency of the United Nations responsible for international public health further said that the predominant lineage of B.1.617 was first identified in India last December. An earlier version of this variant was first discovered in October 2020.
According to WHO, B.1.617 contains three sub-lineages (B.1.617.1, B.1.617.2 and B.1.617.3), which differ by few but are potentially relevant mutations in the spike protein as well as prevalence of detection globally. The sub-lineages appear to have higher rates of transmission, including observed rapid increases in prevalence in multiple countries.
Where was the B.1.617 found?
There is not enough data around where exactly the B.1.617 variant was found first. The Indian state of Maharashtra first reported the detection of this variant. In January, 19 samples from various districts were sequenced, and B.1.617 was found in four of them. In February, 234 samples were sequenced from 18 districts, and 151 samples from at least 16 districts had this variant. In March, as many as 65 of 94 samples had it.
As mentioned in The Hindustan Times, the three lineages of a variant of the SARS-Cov-2 virus now accounts for 66% of all samples tested in the recent 45 days in India.
The variant has now spread to many parts of the world with a rapid increase in prevalence in several regions. An open-access database published by WHO reveals that over 4500 sequences have been uploaded to GISAID and assigned to B.1.617 from 44 countries in all six WHO regions, and WHO has received reports of detections from five additional countries.
Which factors are responsible for the increased transmission of Covid-19 in India?
According to a recent risk assessment of the situation conducted by WHO, increase in the transmission of COVID-19 in India had several potential contributing factors including an increase in the proportion of cases of SARS-CoV-2 variants with potentially increased transmissibility; several religious and political mass gathering events increased social mixing; and under use of and reduced adherence to public health and social measures (PHSM).
On May 9, Soumya Swaminathan, an Indian paediatrician and clinical scientist said, “B 1.617 has some mutations which increase transmission, and which also potentially could make (it) resistant to antibodies that are generated by vaccination or by natural infection”. She further warned that “the epidemiological features that we see in India today indicate that it’s an extremely rapidly spreading variant.”
Could B.1.617 be fueling the ongoing surge in Covid19 cases?
While speaking with The Indian Express, an Indian researcher pioneering Precision Medicine and Clinical Genomics, Dr. Vinod Scaria said that we cannot conclusively say that these variants are driving the surge in the second wave. Some evidence suggests that in some states, the B.1.1617 lineage is predominant, and could be contributing to the rise in cases. “This lineage is defined by 15 genetic variants including six spike protein variants. Two of these are E484Q and L452R that are involved in immune escape as well as increased infectivity,” he said.
Senior Indian virologist Shahid Jameel said, “Double mutation in key areas of the virus’s spike protein may increase these risks and allow the virus to escape the immune system. There may be a separate lineage developing in India with the L452R and E484Q mutations coming together.”
Are the vaccines efficient in fighting the new variant?
Some Scientists believe that the existing vaccines might help control the new variant when it comes to preventing severe disease.
A study published by Indian SARS-CoV-2 Genomic Consortia and the scientists of the Cambridge University in the UK in the bioRxiv, an open-access preprint server said, “Extensive vaccination will likely protect against moderate to severe disease and will reduce the transmission of B.1.617 given the in vitro neutralisation data we and others have presented.”
White House chief medical adviser and America’s top pandemic expert Dr. Anthony Fauci said, “Covaxin has been found to neutralise the 617 variant of the deadly virus. So, despite the real difficulty that we’re seeing in India, vaccination could be a very, very important antidote against this.”
A report published by The Hindustan Times mentioned a statement by Dr Anurag Agarwal, director of the Institute of Genomics and Integrative Biology where he said, “What we found was a reduction in the ability of the antibodies to neutralise this variant, but they weren’t ineffective. There are infections reported in vaccinated individuals but all vaccines protect against severe disease”.