XBB prevalent Covid variant in international travellers, show India's tests

Omicron variant blamed for 40% of all cases being reported in the US

India’s whole genome sequencing (WGS) of international passengers who tested positive for Covid-19 in the last two weeks shows that “XBB” is the most common sub-lineage of the virus among them.

Data released by the Union health ministry on Thursday showed that around 905,647 passengers came to India since December 24, 2022. Around 19,227 samples were tested and around 124 were found to be Covid-19 positive. All the samples that tested positive were sent for WGS, and so far 40 reports have been received.

As many as 14 samples of the 40 were of XBB variant, while BQ1.1, BQ 1.122, BQ 1.1.5 strains were detected in nine samples (see chart).

India is testing two per cent of all international air travellers irrespective of their port of departure, responding to Covid-19 cases surging in some countries. Health Minister Mansukh Mandaviya said in December that the government has mandated RT-PCR test for travellers from China, Hong Kong, Japan, South Korea, Singapore and Thailand from January 1.

XBB is causing a surge in re-infections in the US and other parts of the world, evading immunity gained from vaccination and prior infection. This relative of the Omicron variant is roughly behind 40 per cent of all cases being reported in the US.

India, which has administered more than 2.2 billion vaccine doses to its citizens already, has not reported any surge in cases so far. It is reporting daily fresh cases in the range of 160-200. On Wednesday, India had tested 190,000 samples.

Omicron variant XBB is the most prevalent in India, said a weekly bulletin by the Indian SARS-CoV-2 Genomics Consortium (INSACOG), a scientific advisory group, on December 12, 2022.

“Omicron and its sub-lineages continue to be the dominant variant in India. XBB is the most prevalent sub-lineage (63.2 per cent) circulating all over India. BA.2.75 and BA.2.10 were also circulating to a lesser extent. Especially, in Northeast India, BA.2.75 is the prevalent sub-lineage. However, any increase in disease severity or hospitalisation has not been observed over this period,” the bulletin said.