PUNE: The recently discovered Delta Plus variant of the SARS-CoV-2 virus will be isolated and grown at the Pune-based ICMR-National Institute of Virology (NIV) to test if it can be neutralized with Bharat Biotech’s Covaxin.
The NIV will isolate the variant from samples collected from Covid cases involving Delta Plus reported in India, Dr Samiran Panda, chief of epidemiology and communicable diseases (ECD), told TOI on Saturday.
Dr Pragya Yadav, head of NIV’s maximum containment facility, said: “As soon as it is isolated and cultured, serum samples drawn from those given Covaxin will be used in the lab to test if they can neutralize Delta Plus.” The NIV team said serum samples from recovered Covid patients will also be used to gauge the neutralization potential of the antibodies against the variant.
Not many cases of the latest variant have been detected in India.
According to the Global Initiative on Sharing All Influenza Data (GISAID), Delta Plus has been found in at least seven Covid-19 cases in the country.
GISAID is an open-access global initiative that boosts rapid sharing of data linked to the influenza viruses and the coronavirus-causing Covid-19.
Delta Plus, or the AY.1 variant, formed after the Delta variant mutated further.
Preliminary data indicates Delta Plus shows signs of resistance to monoclonal antibody cocktail treatments being tried in India.
AY.1, or B.1.617.2.1, is characterised by the K417N mutation in the spike protein of SARS-COV-2, which helps the virus enter and infect human cells.
“There is only one extra mutation in Delta Plus.
We still do not know how much this mutation allows SARS-CoV-2 to escape antibodies.
All that has been said so far, about this variant’s ability to escape antibodies, is speculative and needs more analysis,” Dr Yadav said.
Dr Sujeet Kumar Singh, director of the National Centre for Disease Control (NCDC), told TOI any mutation over and above the Delta mutation (B.1.617.2) in the variant is called Delta Plus.
The Delta variant with the K417N mutation is B.1.617.2.1 (AY.1) and colloquially known as Delta Plus, he said.
Dr Singh said, “The immune-escape ability of the variant is still not established.
But it is said it can have an immune escape property, as this mutation is also there in B.1.351 (Beta variant).
Its resistance to monoclonal antibody cocktails is being studied.
As of June 18, 205 sequences of AY.1 lineage have been detected worldwide, with US and the UK reporting over half the known cases.
As of now, two things are important: the number of Delta Plus cases are fewer in India, and scattered.
Two, the variant’s potential of high transmissibility, immune-escape effect and virulence are being studied.”