The variant of concern

The sun is shining as the UK comes out of its winter hibernation lockdown after a traumatic winter. Yet, despite a hugely successful vaccination campaign and a massive increase in testing, many people remain deeply concerned. Most of this concern surrounds variants to the Wild Type - the strain of the COVID-19 virus with no significant mutations.

There is good reason to be concerned about variants ("Variants of Concern"). The second wave of COVID-19 in the UK has been dominated by the B117 variant, which appears to have originated in Kent. Unlike the Wild Type, B117 is both more transmissible and causes more severe illness. In numbers:

  • without social distancing, each person infected with B117 is likely to infect 3-4 other people compared to 2-3 others for the Wild Type

  • for every 100 +80 years olds infected with B117, 82 will become critically ill, and 16 are likely to die compared to 50 and 10 for the Wild Type

More cases and more critically ill people means more pressure on the NHS, which has triggered the need for both of the major national lockdowns.

The positive news is that the first generation of COVID-19 vaccines is effective at reducing both:

  • people getting infected, which means they won't get sick or pass on the virus to others; and

  • people becoming critically ill or dying if they do get infected

These effects are good since they mean the risk of a third wave of COVID-19 is reduced, and the impact on the NHS is also reduced. Provided the UK continues its heroic vaccine rollout, and there is some social distancing over the next few months, we should see B117 pushed into submission - just don't plan on going to any big events.

Given that the B117 variant of COVID-19 is widespread in the UK and under some control, it is not a concern. So how much should we be concerned about other "variants"?

Since the pandemic started, there have been over 137 million reported cases of COVID-19 (certainly a vast underestimate of total actual cases). From this massive number of infections, there have been around 4,000 variants identified. Of these 4,000, only four are currently recognised as Variants of Concern in the UK (four more variants are "under investigation"). Two of these Variants of Concern are homegrown - B117 and B117 with the E484K mutation.*

The two other Variants of Concern are B1351 (South Africa) and P1 (Brazil). Much less evidence is available on these variants - this uncertainty in and of itself creates concern. But at the moment, neither of these variants appears more transmissible nor more deadly than B117. Current evidence also suggests that vaccinations effectively reduce the number of people who get critically ill or die after becoming infe