Kolkata, Dec 30 (IANS): The new and more contagious Covid-19 strain has been detected in a Kolkata resident who came back from the United Kingdom (UK) this month, a West Bengal health department official said.

He is among at least two people to have tested positive for Covid-19 in Kolkata after he had arrived at Kolkata's Netaji Subhas Chandra Bose International (NSCBI) airport.

According to health department sources, one person is found to be carrying the new strain and he is now kept in isolation at a state-run medical facility in Kolkata. All precautions have been taken. In fact, the persons with whom he came in contact with during the journey have also been asked to stay in isolation.

Meanwhile, the Union health ministry on Wednesday said at least 20 of the infected people have been kept in isolation and the fellow travellers and close contacts were also being traced and quarantined.

The UK flight came to NSCBI airport carrying 222 passengers of which 25 passengers did not their Covid-19 reports. They were taken to the nearest Covid testing centre and two of them were tested positive for Coronavirus.

Sources said that one of them was admitted to the Calcutta Medical College and Hospital while other person was shifted to Rajarhat's CMCI. Their test samples were sent to Pune for further verification to confirm if they were carrying the new strain of Coronavirus.

A new strain of the coronavirus has emerged in the UK sparking off serious panic in many countries, including India. The new strain of Covid-19, code-named as B.1.1.7, has been widely tracked in the UK in the recent times.