A 24-year-old man who returned from Ireland to Kolkata was found to be infected with the omicron variant of coronavirus on Friday, health officials said.
At present, West Bengal has three Omicron patients who are undergoing treatment, they said.
The new patient got admitted to a hospital on December 21, following which his sample was sent for genome sequencing and it came back as positive for omicron, a health department official said.
The patient is undergoing treatment in an isolated room in the restricted COVID unit of the hospital since his admission, he said.
"The patient is haemodynamically stable and relevant conservative medical management is going on," he added.
Earlier, a person who returned from Nigeria, and another person who came back from the UK were found to be infected with the omicron variant.
A seven-year-old boy who came back from Abu Dhabi via Hyderabad was also omicron-positive but he has recovered.
West Bengal on Friday reported 550 new COVID-19 cases and five more deaths, as per the daily bulletin.
The state has so far reported 16,29,530 COVID-19 cases and 19,707 deaths.
Kolkata, North 24-Parganas, South 24-Parganas, Hooghly and Birbhum districts reported one death each.
Of the new cases, 217 were reported by Kolkata.
The state now has 7,446 active cases.
So far, 16,02,377 people have recovered from the disease, including 532 on Friday.
The new cases were detected after testing 37,016 samples