Thread by @JeremyFarrar

There is lots of high-quality data on COVID-19, but we haven’t always done a good job of explaining what it really means, or put the data in context of a fast moving dynamic epidemic, when days matter. So I am going to have a go.

The @ONS have provided outstanding data & I'm proud @wellcometrust are a partner along with @OfficialUoM, @UniofOxford, @PHE_uk - @Join_ZOE, Pillars 1-4, Test-Trace-Isolate, @ISARIC1 CO-Cin, Public Health in Scotland, NI, Wales, #NHS, COG-UK, in Schools, Care Homes & many more

But looking at figures released today is like looking back in a rear-view mirror. When look at data on number of deaths today, we're seeing how prevalent infections were & state of the epidemic up or more than a mth ago.The data doesn't show you the state of the epidemic today

For those who tragically die from this virus, there is a lag time of up to & sometimes more than a month from time of infection, to testing positive to their tragic death. Deaths we see today show the infection problem, transmission & state of the epidemic we faced in September.

But we know transmission & infections have been growing rapidly since then, the epidemic is very dynamic & expanding, prevalence is high & r is well above 1. Which means, sadly, inevitably, we will see cases, illness, hospitalisations & deaths growing in the days & weeks ahead.

We’ve surpassed the ‘reasonable worst-case scenario’ @uksciencechief & @CMO_England & SAGE outlined in Sept. We won’t see very sad consequences of the level the virus is transmitting today until start Dec.That is the dynamic of the consistent evidence based scientific projections

The best time to act was a month ago but these are very tough decisions which we would all like to avoid. The second-best time is now. The sooner we get on top of the disease, reduce transmission, r<1, the sooner we can get our society back to normal & the economy back on track.

Nobody 'wants' a lockdown, myself very much included. Full & generous support for people & businesses is a crucial part of making it work. But we have quickly breached the reasonable worst-case scenario, we are further ahead in this phase of the epidemic than many have assumed.

Sadly, there is now no easy path ahead, just the least bad option. To bring #COVID19 under control, we have to act now. The virus will not wait for us.

For a way of visualising what the time lag means this from @HarvardChanSPH showing the lag between cases and deaths in the USA.
hsph.harvard.edu/news/hsph-in-t…

Or for how the epidemic spread in the USA from - 23 seconds shows the spread from March-September from @CovidActNow (thank you)
blog.covidactnow.org/covid-spread-u…

The coming months are going to be very difficult in UK, in Europe and North America. But we can & will get through this. We will be in a much better position in early 2021, when we will start to see better diagnostics, effective vaccines & treatments.

But have act now, reduce transmission, reduce hospitalisations, protect vulnerable & #HCW,reduce illness due to COVID & non-COVID, & more lives we can save. Quicker UK & all countries can get back on their feet. Health,COVID & non-COVID & Economies are linked & interests aligned

Good weekends all.