In my last entry, I mentioned a new strain of SARS-CoV-2 (B.1.1.7) characterised by numerous mutations including ∆H69/V70 and N501Y in the spike (S) protein. This strain is rapidly increasing as a proportion of all UK strains in circulation, especially here in the South-East of England. PHE thinks it is more infectious than pre-existing strains. In vitro, the ∆H69/V70 S protein promotes cell invasion via the ACE2 receptor more efficiently than the ancestral protein. B.1.1.7 may have evolved to escape anti-S antibodies in plasma, at least in part, by invading target cells rapidly thereby "hiding" from antibodies. To date, there are no data to suggest it is intrinsically more deadly than ancestral strains.

The brilliant genomics surveillance of the virus in the UK deserves our grateful thanks for the detection and analysis of B.1.1.7. About half of all SARS-CoV-2 genomic sequences worldwide have been UK genomic surveillance.

Reuters has an excellent account of coronavirus mutations and their spread around the world. National Geographic has more of the story on the strains and their origin.

When the government announced the discovery of this strain – and the threat it posed – it hoped that this would help people understand the need to increase the tier restrictions in England. However, unsurprisingly (and predictably) it spooked overseas governments, who promptly announced travel bans from the UK.

Among the bans was all cross-channel traffic. This led to the immediate stoppage of lorry traffic crossing from Dover to France. Within hours, trucks were filling the runway at Manston airport, and Operation Brock was put in place to have an orderly back up of trucks parked on the M20. So many trucks were involved, that they seemed to litter any spare parking place in Kent, and presumably further afield. Many of the truckers are from central and east Europe, EU citizens returning home for Christmas blocked from entering the EU.

Little provision for the individual truckers seemed to have been put in place ahead of time: this was disgraceful given the possibility of a no-deal Brexit in a few days time with consequential travel chaos (although, thankfully, that is now not happening). There seemed to be little to no provision for food/water/hygiene outside the drivers' cabs. As a result, volunteers from all over Kent (and further afield) provided food and water: among others, the Sikh community provided food from their kitchens. My friend Zuzu, who is Czech, went on an emergency run to provide food. The only way to resolve the issue was to use lateral flow tests for the drivers: around 15,000 tests were given in a couple of days; 800 UK troops were deployed in support of this. 25 sapeurs-pompiers du Nord and 37 Polish doctors, nurses and technicians flew in and contributed to the testing. Days on, the travel ban continues to wreak havoc on Kent’s roads.

All this despite the European transport commissioner saying that blocking cross-Channel traffic is wrong, because drivers in their cabs are socially isolated and pose little threat. The commissioner was correct about this: around 0.2% of the drivers tested positive, less than the background rate in the population. In any case, S∆H69/V70 has evolved independently many times, and has been known on the continent for some months (e.g. in the Czech Republic and Denmark). Compared to the UK, genomics surveillance is relatively lacking in EU (and most other) countries, so its prevalence is largely unknown. Nevertheless, B.1.1.7 is now making its way around the continent, as well as other places around the world.

It was against all this background that we went for a family walk at Hothfield Heathlands on Christmas day, something of a family tradition. On the way there, we crossed a bridge over the M20 and could see Operation Brock in place. Driving on the A20 to Hothfield, we passed trucks parked in every possible place, waiting for the chance to head home.

Later that day, I headed back to the bridge over the M20 to get a record of this moment. The opening picture shows trucks on the afternoon of Christmas day parked up. They stretched back way out of view, nose-to-tail.

What a way to spend Christmas in 2020.