New @cmmid_lshtm analysis (led by @Jarvis_Stats @KevinvZandvoort) looked at UK social interactions on 24–26th March (just after lockdown) and found a 70% reduction in daily social contacts relative to normal levels. cmmid.github.io/topics/covid19… 1/
Typically, people in UK make about 10 daily contacts on average – after lockdown this dropped to around 3 daily contacts among the surveyed sample of 1,356 UK adults (which was designed to be representative of age, gender, and geographical location). 2/
If this reduction in social interactions holds across the population, a simple age-structured model would suggest the reproduction number of COVID-19 in the UK is now likely to be below 1. 3/ 
For context, several studies have shown that these age-specific contact patterns can capture key aspects of the transmission dynamics of respiratory infections, e.g.
academic.oup.com/aje/article/16…
sciencedirect.com/science/articl…
journals.plos.org/plospathogens/… 4/
academic.oup.com/aje/article/16…
sciencedirect.com/science/articl…
journals.plos.org/plospathogens/… 4/
It's worth noting, of course, that any decline in COVID-19 transmission will take a week or two to show up as a change in case data (because of the incubation period and delay to reporting), and up to a month to show up as a change in deaths. 5/5
