Six cases of a mutant strain of coronavirus that first surfaced in the UK, have been detected in the country. The new strain is believed to be 70 per cent more infectious, but doctors have said there is no reason yet to believe that it is more lethal or will not be controlled by a vaccine. All six patients have recently returned from the UK, where cases have spiralled within days.

Three of the patients are in NIMHANS, Bengaluru, two in Centre for Cellular & Molecular Biology, Hyderabad and one in National Institute of Virology, Pune.

All patients have been kept in "single room isolation" in designated healthcare facilities by the state governments. Their close contacts have also been put under quarantine. Comprehensive contact tracing has been started for co-travellers, their families and others, the government said. 

Around 33,000 passengers arrived from the UK between November 25 and December 23. Of them, 114 have tested positive for Covid.  Genome sequencing for other specimens is on, the government has said. The states where these passengers arrived, meanwhile, is tracing them and their contacts for Covid RT-PCR tests.

The UK strain surfaces at a time the spread of the infection -- after hitting a peak in September -- has slowed down. Over the last 24 hours, the country logged 16,432 cases -- the lowest since June 24, when 15,968 cases were recorded. The overall coronavirus figure is now 1,02,24,303, the highest after the US.

"The situation is under careful watch and regular advice is being provided to the States for enhanced surveillance, containment, testing & dispatch of samples to INSACOG labs," read a government statement announcing the UK strain.