One confirmed XE case in India, no reports of clusters in country

India now has a confirmed case of a person infected with the XE variant, according to Indian SARS-CoV2 Genomics Sequencing Consortium (INSACOG) bulletin. The location is not known yet.

INSACOG is a network of national testing laboratories set up by the government. In the bulletin for April 18 and 25, INSACOG mentions that one case of XE has been confirmed in the country. The location of the person is not yet known, and the Union Health Ministry is yet to issue any statement on the matter.

In the latest bulletin, INSACOG said that Omicron (BA.2) is the dominant variant in India till date. “As compared to the previous week, 12 states have shown an increase in cases, while nineteen states have shown a decline,” it said, adding that suspected recombinant sequences are under further analysis.

“BA.2.10 and BA.2.12 are BA.2 sub-lineages that have been detected and many old BA.2 sequences have been reclassified into these new sub-lineages. So far these sub-lineages are not reported to be associated with increased severity of disease,” the bulletin said.

Detailing the distribution of the variants of concern (VoC), INSACOG bulletin said there were 4266 Alpha variants, 220 Beta, 3 Gamma, 43928 Delta, 5607 of B.1.617 and B.1.617.3, 20450 AY series, 45359 Omicron, and 1 XE variant in the total 119,834 samples sequenced.

Therefore, one case of XE is confirmed in the country.

Experts have said that the XE sub-variant is 10 per cent more transmissible than the dominant BA.2 variant of Omicron, which had triggered the third wave in the country in January.

So far there are no reports of XE clusters across India.

The BA.2.12.1, the Omicron sub-lineage that is causing the rise in Covid-19 cases in the National Capital Region (NCR), has a mutation in the spike protein which is akin to a mutation found only in the Delta lineage. Whether this causes any severity in infections is to be seen, but so far, clinicians claim that most Covid-19 positive cases are asymptomatic or mild.

Speaking to Business Standard, Shahid Jameel, ssenior research fellow at Green Templeton College at Oxford University explained that Omicron now has two main lineages – the BA.1 and the BA.2 – both with several sub lineages. “As a group, BA.2 spreads about 20 percent better than BA.1,” he said, adding that there are two key mutations in the spike in BA.2.12.1.

“There are two key mutations in Spike in BA.2.12.1 that are missing from BA.2.12 and other sub lineages. These are L452Q and S704L. Of these a similar (not identical) mutation L452R is found only in the Delta lineage,” Jameel explained.

How the XE variant behaves in terms of spread and degree of infection is yet to be seen. Business Standard