For the last few months, the UK seemed to have had the virus under control. Between the end of June and the end of August, new weekly cases per 100k had remained under 10 (see dashboard for our data). It is worth noting that this period included the several weeks following the lifting of lockdown – a time when lockdown restrictions were eased significantly. The public started mingling in larger groups, eating in restaurants again, went to their favourite local pub, returned to their physical places of work, increased their leisure activities and booked holidays. This caused no material increase in the case data. However, since the end of August the weekly cases per 100k has been increasing to the point that it is now in the high-teens.

This caused Boris Johnson to implement a new strategy last night, called the ‘rule of six’, where gatherings will be restricted to a maximum of six people indoors, outdoors and in private homes (starting on Monday 14th September). However, there are a number of exceptions to this rule. So many, in fact, that the rule itself has already come under great scrutiny. With workplaces, schools, universities, protests, funerals, weddings (to name a few!) on the exemption list, it’s hard to see how useful or effective this strategy will be. Looking at the numbers, a weighted moving average (WMA) of daily COVID cases in the UK on Sunday 6th September showed 1,982 cases instead of 2,988 new cases in 24 hours. Not quite “record breaking” as the sensationalist headlines suggested. Granted, the trend in daily case numbers is increasing, but the rate of increase is slower than that experienced at the end of March. Back then, the UK’s weekly cases per 100k number went from 7 to 30 in 13 days. Now, the UK’s figures have gone from 9 to 18 in 15 days – a much smaller increase in a longer frame of time.

The increasing daily cases in the UK can be partly attributed to the increase in daily tests. At the start of September, more than 175k daily tests were being processed in the UK. Cumulatively, the UK has tested more than 25% of its entire population. This is a good thing. The more testing, the reduced likelihood of someone who is positive but asymptomatic spreading the disease. The more testing, the greater the accuracy of the data and the better understanding we have of how the virus behaves. The side effect is that more testing will expose more cases, and thus the ‘growth rate’ of the virus will increase.

The situation in the UK is quite different to say, India. In India, the weekly cases per 100k increased from 7 weekly cases per 100k on 30th June, to 37 on 9th September. During the same period, the UK’s weekly cases per 100k went from 7 to 19. Hence, India’s rate of increase is significantly higher than the UK’s. Given that India has also been ramping up its testing, having achieved a record of 1.17 million tests in 24 hours (Wednesday 2nd September), it’s clear that both countries have seen more cases as a result. Yet, the spread of the virus is occurring in two very different ways.

For the UK, does the uptick in cases suggest lockdown restrictions like ‘the rule of six’ should be re-introduced? Probably not. The lifting of lockdown is clearly not the direct contributor to increased cases. Instead the UK should keep lifting restrictions, keep testing and keep reviewing the case data alongside the critical context of the data. In parallel, we should get people back to the office, back to leisure activities and back to travel.