Finally, Centre flags surge link to double mutant

However, the Centre added a key caveat: the epidemiological and clinical correlation of B.1.617 and the surge is not “fully established”.

Significantly, the Centre included B.1.617, under the category of “Variant of Concern,” along with B.1.1.7 (UK variant); B.1.351 (South Africa variant), and P1 (Brazil variant).

Having said that, the data reveals a telling pattern. Of the about 13,000 samples sequenced, 3532 were found to have Variants of Concern. Of these, 1527 had the B.1.617 variant.

The majority of this was been detected in samples collected from surge states: Maharashtra (761); Karnataka (146); West Bengal (124); Delhi (107); Gujarat (102); Chhattisgarh (75); Jharkhand (61); and Madhya Pradesh (53).

Of the 1527 which had the B.1.617, only 23 were linked to international travel, the rest were all part of the community spread — local population.

“Initially, the epicentre for B1.617 lineage was found to be Maharashtra. The current surge in cases seen over the last one and half month in some states shows a correlation with rise in the B1.617 lineage,” said Dr Sujeet Singh, Director, National Centre for Disease Control.

“However, its epidemiological and clinical correlation is not fully established…without the correlation, we cannot establish direct linkage to any surge. However, we have advised states to strengthen public health response — increase testing, quick isolation, prevent crowds, vaccination — in those regions where presence of B.1.617 has been noted,” Singh said.

Singh said that information on genome sequencing was shared with states twice in the month of February; four times in March; and four times in April.

The Indian Express had also reported that following a request from the United Kingdom, samples of the double-mutant are being sent to London to enable wider studies on the effectiveness of the existing vaccines against it.

On Wednesday, Renu Swarup, Secretary, Department of Biotechnology, reiterated that genomic sequencing data, in isolation, doesn’t give “us any indication unless and until it is correlated with clinical data.”

But she underlined that preliminary data shows vaccines are effective against the double mutant variant.

“We have also prepared neutralisation assays of these variants and all vaccines are being studies. Preliminary data shows that our vaccines are effective,” Swarup said.

Experts had earlier told The Indian Express that because both the mutations of B.1.617, E484Q and L425R, were located in the virus’s critical spike protein — that binds it to the receptor cells in the body – its destructive potential should have raised red flags and led to widespread gene surveillance.