Thread by @BarnardResearch

A lot of attention on our @cmmid_lshtm preprint on the SARS-CoV-2 VOC 202012/01. For some background, the precursor work on a (single-variant) model looking at tiered restrictions and lockdown in England was published last night: authors.elsevier.com/sd/article/S14… ✨PEER REVIEWED(!)✨ 1/9

We fitted a (single-variant) model of SARS-CoV-2 transmission to the first and second waves in England from March - October 2020, using a number of data sources across NHS England regions 2/9

We used mobility and contact survey data to assess the effects of regional tiered restrictions (Tiers 1, 2, 3) introduced in England in October 2020 (pictured), and the effects of the Welsh firebreak 🔥 Northern Irish circuit breaker 🔐 lockdowns 3/9

On 31st October, the UK government announced a four-week lockdown in England from 5th November 2020. We used our measured responses to NI and Welsh lockdowns to project the impact on transmission of this new lockdown in England (Tiers + Wales effect pictured) 4/9

We projected the effect on deaths, healthcare burden and time under restrictions of different interventions, with and without school closures. Also considering different lengths and timings of lockdown interventions 5/9

Later, we assessed the true impact of the English tiered restrictions and lockdown as well as the projected lockdown scenarios (NI and Wales) on the reproduction number 6/9

The original report we wrote is here cmmid.github.io/topics/covid19… and the code is here github.com/nicholasdavies… 7/9

This work was done before the novel SARS-CoV-2 variants were of concern, which led us (in the last 5 days!) to update the transmission model to consider two variants (see

https://twitter.com/_nickdavies/status/1341845176361349123?s=20

for the lowdown) 8/9

With huge thanks to @cmmid_lshtm and @CCPUKstudy for their inputs, and @_nickdavies for leading the work. Work also in collaboration with @markjit John Edmunds and Calum Semple, who I could not tag above. Time to wrap presents.... 🎁🎄 9/9