XBB 1.16 variant likely behind surge of Covid infections in Telangana

A fast-spreading new recombinant variant XBB1.16 of SARS-CoV-2 is believed to have originated in Maharashtra

Hyderabad: A fast spreading new recombinant variant XBB1.16 of SARS-CoV-2, believed to have originated in Maharashtra and then reported elsewhere, is now behind the fresh surge of Covid infections in Telangana, Maharashtra, Gujarat, Karnataka and other States.

For the past few days, the Covid positivity rate in several States, including Maharashtra, Karnataka and Gujarat, has increased, which has also coincided with the rise of the seasonal H3N2 influenza. In a single day, the Maharashtra health department on Tuesday reported 155 positive infections and two-related fatalities while Telangana recorded 52 positive infections on Tuesday and 54 on Wednesday.

The genomic data of new SARS-CoV-2 variants in the last week of February and the first week of March, which is collected by GISAID, the international body that tracks new SARS-CoV-2 variants worldwide, has given clear indications of the dominance of XBB 1.16 in several Indian States.

Based on the available information from biologists and geneticists who are vigorously tracking and identifying new variants, the percentage of growth of XBB 1.16 during January and February in India was nearly 2 per cent and by March, the growth rate increased to nearly 40 per cent. While not much information is available on the virulence of XBB 1.16, the new variant, however, is able to evade immunity, a big reason why it is spreading at a quick pace.

It is believed that the new recombinant variant first came into focus when Indian travellers tested positive for it in Singapore. At present, apart from India, the XBB1.16 variant is actively in circulation in the United States, Singapore and Brunei.

Till recently, the XBB 1.5 has been the dominant lineage of SARS-CoV2 in the country. Recombinant variants of SARS-CoV-2 like XBB and XBB1 and emerging new variants like XBB 1.16 are generated when two or more viruses together infect a cell at the same time.

While the probability of co-infection is quite rare, recombination of Omicron sub-lineages has occurred in India, leading to recombinant variants. The XBB is a recombinant lineage of two Omicron sub-lineages including BA 2.75 and BJ 1. Based on GSAID data, the XBB 1.16 and XBB 1.5 are the direct descendants of XBB and XBB 1.