India records two new Covid variants; is there anything to worry about

The two new variants, called NB.1.8.1 and LF.7 are sub-variants of the Omicron variant that was active till 2022. NB.1.8.1 is a descendant of the JN.1 variant, while LF.7 is another offshoot related to it. These variants carry multiple mutations in the spike protein of the virus, which help it transfer quite easily to humans. For example, NB.1.8.1 has mutations like A435S, V445H, and T478I that may increase its transmissibility.

According to latest INSACOG data, one case of NB.1.8.1 was detected in Tamil Nadu in April 2025, and four cases of LF.7 were found in Gujarat in May 2025. Across the world, NB.1.8.1 has been detected in over 20 countries, including Asia, US, Japan and South Korea.