Generally, the spread is seen moving from the west to the east of the country. But given that pattern, it would have taken longer for the surge. This did not happen, which shows that Omicron is rapidly replacing Delta," Niti Aayog member (health) Dr VK Paul said during the weekly press conference of the health ministry.

Echoing the recent concerns expressed by the World Health Organization that people are considering Omicron as mild and which is not right, Dr Paul said, "Omicron is not a common cold. It is not so simple and neither should it be taken so lightly. And even if Omicron appears less severe, it is because of the extensive vaccination coverage that we have achieved. The same Omicron has challenged the health infrastructure of many countries."