Dr NK Arora, Chair of the COVID-19 working group of National Technical Advisory Group on Immunisation (NTAGI) said, "Variant is very important and currently among four variants, Indian variant, that is, B.1.617 is overtaking rest of the variants. It is circulating in the country which has three sublineages. Out of the four variants variant, 617 has overtaken all other variations at the moment. People are worried that if it goes out globally it will spread very rapidly." "At the moment one of the major issue is variants or mutations. The mutation is not a national but a global problem. All over the world people are worried because the vaccines have been rolled out but if vaccines are not effective against these mutations or the variants then one will have to work. So at a larger scale, four things are very important for variants of mutations which are being studied," added Dr Arora.