Global Virus Network issues guidance on new Covid-19 variant

The newly identified Covid-19 variant, named NB.1.8.1, is spreading rapidly across parts of Asia including India and other regions such as the United States.

While the variant has sparked concern due to its rising numbers, global health experts are urging caution, not panic.

The Global Virus Network (GVN) - an international coalition of top virologists and research centres - which is closely tracking the situation, says there is no current evidence that NB.1.8.1 causes more severe illness than earlier variants.

However, its growing presence has led the World Health Organisation (WHO) to list it as a 'Variant Under Monitoring.'

The variant, a sub-lineage of the Omicron family, was first detected in January 2025 and has now been found in 22 countries.

As of May 18, 2025, NB.1.8.1 accounted for 10.7% of global Covid-19 virus samples submitted to the international database GISAID, global science initiative and primary source for freely sharing



genomic data of viruses, especially influenza viruses.

This is a sharp rise from just 2.5% four weeks earlier. In India, active Covid-19 cases have climbed to 6,491 (as of June 9), with more than 500 new infections reported in the past 24 hours.

States such as Delhi, Kerala, Gujarat, Uttar Pradesh, and West Bengal are reporting steady increases in cases.

Other countries are also seeing a rise. In Taiwan, hospital visits due to Covid-19 symptoms rose by 78% in one week, with nearly 6,000 people seeking care between April 27 and May 3.

In the United States, more than a dozen cases of NB.1.8.1 have been reported, initially detected through airport screenings in California, Washington, Virginia, and New York. The variant has since been found in Ohio, Rhode Island, and Hawaii.

Despite the rise in infections, experts say the pattern remains consistent with seasonal surges, and vaccines continue to provide strong protection against serious illness.