When the story of the new Covid-19 variant broke, my initial reaction was scepticism. I thought this new strain could just be a random genetic marker that coincided with an outbreak of cases that was caused by behaviour (or even “chance”) rather than by any important biological differences. We have more sophisticated measurement capability for biological data than for social data, and I worry that not enough has been done to rule out social explanations.
For example, despite Covid-19 cases rising dramatically since September mobility indices have remained above the levels they saw in June, which were significantly higher than their April lows. So the UK’s November lockdown only temporarily slowed large scale community spread and did not get it under control.
We already know that people are changing their behaviour. Schools have reopened. We did not need any special biological explanation for why cases have continued increasing.
As we’ll see below, the most rapid increase has occurred in London where the estimated percentage of the population testing positive has likely surpassed 2 per cent.
