Coronavirus: Glasgow's Indian variant outbreak is a warning against 'traffic light' travel

Nicola Sturgeon described the ‘red list’ system as “a bit too leaky” as the Scottish Government repeatedly, and to no avail, urged the UK Government to enforce blanket supervised hotel quarantine to all returning passengers, as was being introduced north of the border.

READ MORE: Glasgow to remain under Level Three restrictions

The UK Government demurred, insisting that the danger was low given that non-essential travel was already banned anyway, arrivals were required to provide evidence of a negative PCR test before entry, and 10-day home self-isolation would still apply to everyone else.

The pitfalls were obvious: people can test negative and still be incubating the virus, and compliance with voluntary self-isolation at home is wide open to breaches - from people failing to stay home or fully isolate from members of their household (who then go out into the community), to inviting visitors into their home.

There were reports of crowded airports and passengers from red list and non-red list countries freely mingling in queues in poorly ventilated arrivals halls.

It quickly emerged that while the red list (initially focused on the Brazilian P1 and South African mutant strains) covered swathes of Africa and South America, dozens of other destinations such as France, Belgium, Denmark and Canada where these variants had also been detected had been left off.

The strategy was described as “fairly futile” by one virologist, as others repeatedly stressed that we were relying on genomic sequencing in other countries (limited in many cases) to inform our risk assessments.

Yet the pandemic was continuing to rage around the globe, giving the virus ample opportunity to evolve and mutate into potentially harmful new strains that could easily be in circulation for months before they triggered any alarm bells.

READ MORE: More than 92% of older Scots have had both vaccine doses

Meanwhile, Scotland was also left in the absurd position of enforcing costly hotel quarantine on the limited number of international arrivals flying direct into Glasgow, Edinburgh and Aberdeen, while the majority coming in on connecting flights from London or Dublin could head straight home to supervise their own quarantine.

And while this debate went round in circles in February, something predictable happened: a new Covid variant entered the UK.

The first known specimens of B1.617 - the Indian “double mutant” - were picked up in samples processed on February 22.

At the time India was not on the red list; in fact, it was seen as a low risk country where the virus had petered out, with overly optimistic speculation that the country had reached herd immunity through natural infection.

Graph showing how the B1.617.2 variant has come to dominate in India (Source @TWenseleers)

By the time this strain was designated a ‘variant under investigation’ by UK authorities in mid-April, there were already 77 known cases here - 73 in England and four in Scotland.

It has since been split into three subtypes, with the B1.617.2 “variant of concern” alone now responsible for at least 35 cases in Scotland as of May 10th and 1,313 cases UK-wide by Thursday.

In some parts of England, including Bolton, Blackburn, Bedford and South Northamptonshire, the B1.617.2 is accounting for between 54 per cent and 77% of cases analysed.

READ MORE: Why UK scientists are growing worried by the Indian variant

It is believed to be driving the surge in cases in Pollokshields where roughly one in every 100 residents is now testing positive.

It is a reasonable assumption that, had supervised quarantine applied universally, we would not now be in the position of putting the brakes on Glasgow’s exit from lockdown.

Some will ask why this variant poses a threat at all given our high vaccination coverage: a third of all adults are fully vaccinated, including 94% of over 65s, and two thirds of all adults have had at least one dose.

First (blue) and second (purple) vaccine doses by age group

But 65% of adults under-50 in Scotland remain completely unvaccinated, including more than 95,000 people aged 16 to 64 with underlying health conditions.

The Seychelles offers us a cautionary reminder that the virus will find a way.

On Tuesday, the World Health Organisation confirmed it was reviewing data from the Indian Ocean nation where the case rate has soared ten-fold in a month, to more than 400 cases per day in a population of around 98,000 where some 60% are already fully vaccinated (compared to 34% in Scotland).

Around 80% of those needing hospital treatment had not been vaccinated and tended to be people with co-morbidities, according to the health ministry, but 37% of those testing positive had had both doses.

The country uses AstraZeneca and Sinopharm vaccines which the WHO says are between 76-79% effective against symptomatic infection, based on clinical trial evidence.

Back in the UK, a Covid modelling paper for England this week warned that “a variant that is 30-40% more transmissible than B117 [Kent] is projected to generate more total hospital admissions than the first wave” - even if the vaccine works against it - due to comparatively high levels of partial and unvaccinated populations as the roadmap out of lockdown progresses. 

The official line is that B1.617.2 is “at least as transmissible” - but there is growing evidence that it is outcompeting Kent and may in fact be around 60% more transmissible.

Modelling for SAGE expert group showing that even if vaccines provided 100% protection against a new variant, if it were 30% more transmissible (green line and shading) then hospital admissions would still slightly surpass wave one, with much larger surges for 40-50% transmission (orange and blue)

Regardless of whether it causes more severe disease or can ‘escape’ vaccines (there is no clear evidence it does), simply being able to infect more people more rapidly and reach enough who are vulnerable would create havoc.

Crucially, the modelling indicated that the projected surge in hospitalisations would be reduced to modest levels if England delays Monday’s planned reopening.

This has been ruled out, with surge testing and vaccinations in hotspot postcodes rolled out instead and progress into a traffic light system for travel going ahead on Monday which will allow anyone returning from an amber country (the vast majority of countries on the list) to self-isolate at home.

Funnily enough, just like those returning from India did at the beginning of the year.