The WHO has labelled B.1.617.2 strain as the ‘Delta’ variant SARS-Cov-2 and categorized it as a variant of concern (VOC).
The variant, which is believed to have originated in India in December 2020, was identified as one of the drivers of the second wave of Covid-19 in the country.
According to data from initial risk assessments in England and Scotland, the variant is more transmissible than contemporary lineages.
The variant contains multiple mutations, of which at least 4 are of concern: L452R, P681R, D614G, T478K.
According to the WHO, the Delta variant is widespread and has been detected in over 80 countries so far.
According to the global science initiative GISAID, the UK has the highest number of such cases.
Public Health England(PHE) in its latest risk assessment said that a staggering 91% of the samples sequenced were of the Delta variant.
The Delta variant also has a substantially increased growth rate when compared to the Alpha variant, PHE said.
Secondary attack rates have remained higher for Delta than Alpha, PHE added.
There is still little data available about whether the Delta variant causes more deaths. However, PHE has said there is early evidence from England and Scotland to suggest that when compared to the Alpha variant, the Delta variant is more likely to cause hospitalization.
PHE said that both Pfizer-BioNTech and AstraZeneca vaccines are slightly less effective at preventing hospitalization in people with the Delta variant compared to those with Alpha variant.
In India, Health Secretary Rajesh Bhushan said that both Covaxin and Covishield are effective against the variant.
The new Delta Plus variant has been formed due to a mutation in the Delta or B.1.617.2 variant.
According to Vinod Scaria, of the Institute of Genomics & Integrative Biology, the variant can render the antibody cocktail of Casirivimab & Imdevimab ineffective.
As of June 22, 2021, there are 22 cases of the Delta Plus variant in India, namely in Madhya Pradesh, Maharashtra and Kerala, the Govt said.
The Union Health Ministry has classified the variant as a ‘Variant of Concern’.
The agency declared delta a "variant of concern" last month. 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, according to the health organization.
Scientists around the world and in India are concerned about 'Delta plus', an emerging form of the Delta variant of the novel coronavirus, which allows it to “escape” antibodies in recently approved treatment regimes.
