According to latest results from the COVID Symptom study, while infection rates have fallen, this drop has slowed and is beginning to level off.
The REACT-1 study provides regular updates on the prevalence of COVID-19 across the UK based on the results of nose and throat swabs, obtained from a random sample of the population. These latest data, which cover the period up to 13 February 2021, is based on a sample of 85,473 swab results, of which 378 were positive, giving a weighted prevalence of 0.51% compared to 1.57% in the previous analysis that covered January 2021. Similarly, the Office for National Statistics (ONS) latest weekly data (also based a random sample of nose and throat swabs), covering the period up to 12 February 2021, estimates a prevalence of 1 in 115 people, which again, is lower than their previous estimate, also from January 2021. The COVID symptom study is an app-based study which collects self-reported symptomatic data on a daily basis. As such this is the most up-to-date source of information on infection trends, whereas both REACT-1 and the ONS data provide an estimate of prevalence over a slightly longer period of time. Both these surveys indicate that the incidence of COVID-19 has reduced over the last few weeks.
The latest COVID Symptom data, which is based on around 1 million weekly reporters, also shows that the incidence of COVID-19 is declining. Data from the app estimates that there are 14,064 daily new symptomatic cases and this equates to a much lower prevalence of 1 in 294 people in the UK. While these data are more encouraging, suggesting that the rate of infection is falling even more than the estimates from either the REACT-1 or the ONS, the COVID symptom study suggests that the observed fall in new cases has actually started to slow and even plateaued, with the group estimating that the UK R value is 0.9. The reasons for the slowing of cases remains unclear but one theory proposed by the authors is that after vaccination, people have become less guarded. The app data shows that cases have started to rise again in those aged 20–39 but encouragingly that the case rate among those aged 60 and over have started to fall. The incidence of new cases also appears to vary between regions of the UK. For example, the app data indicates that there are 16 to 26 new daily cases in London, but between 15 and 31 in Yorkshire and The Humber.
Nevertheless, while all three sources of incidence data clearly suggests that the infection rate is falling in the UK, there are still a high number of daily cases, which is a cause for concern.
Citation
Data Press release. 19 February 2021. COVID Symptom study. https://covid.joinzoe.com/post/rapid-drop-in-cases-slows-down