FOUR cases of a India's 'double mutant' strain of coronavirus have been detected in Scotland for the first time.

New figures from Public Health England show that 73 cases of the variant, known as B.1.617, have been identified in England with a further four in Scotland.

The variant is characterised by two distinct mutations on its spike protein which are believed to make it more infectious, and potentially more resistant to vaccines.

The discovery of 77 cases of the variant in the UK has raised questions about why the India has not been added to the 'red list' of countries which required travellers to complete a 10-day supervised quarantine in hotels.

Scotland requires all international arrivals to isolate in hotels, but this can be avoided if passengers coming from non-red list countries catch connecting flights via airports in other parts of the UK or Ireland first.

They would still be required to self-isolate, but can do so at home instead. 

Professor Devi Sridhar, chair of global public health and a member of the Scottish Government advisor group on Covid-19, said this showed "why the red list approach just doesn’t work from a public health perspective".

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Deepti Gurdasani, a senior lecturer in epidemiology at Queen Margaret University London (QMUL), tweeted: "Not only do we are we continuing to see rises of the so-called South Africa variant, despite efforts to contain it, we also seem to have imported the double mutant from India - with *77* cases identified so far.

"When were these identified? And why isn't the govt acting?"

The Indian variant was reportedly first detected in England in February and cases are now said to be dispersed across England, with many linked to travel

Details of the location and circumstances behind the cases in Scotland are unknown at this stage

Dr Anthony Costello, a member of Independent SAGE (Scientific Advisory Group for Emergencies), said: "This is a disaster. We have more than 50 flights from India daily. Seventy-seven cases of a really nasty India variant that affects younger people already here?

"Surge testing without isolation support. Contacts not being tested. This is a total shambles. We have learnt nothing after a year."

The Indian variant is characterised by two mutations, known as L452R and E484Q, which have never before being found occurring together in the same variant.  

India's Health Ministry said in March that the combined mutations "confer immune escape and increased infectivity".

India has experienced a massive surge in Covid cases in recent months and on Thursday recorded more than 200,000 new infections in a single day - the highest in the world.