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Covid. England, Notes from epidemiologist, Neil Ferguson.

Source: Adapted from CDC

-Current England strategy = <20K Deaths from COVID (vs 500k no strategy)

-Peak ICU demand in 2.5 to 3 weeks 

-With current strategies + recent surge in NHS capacity = ICUs will have enough capacity though may get close on local level.

-Testing needs significant ramp for strategy shift in 3-4 weeks

-Current strategy => 5 - 10% London is infected, will vary across country. 

-Without suppression/current strategies, Ferguson et al model still suggests 500K deaths and overwhelmed health service 

-Original modelling did not include much on testing + contact tracing as Public Health England made clear that testing was not going to be anywhere near sufficient in Feb/March. 

Notes on listening to epidemiologist, Neil Ferguson (NF), give evidence to Parliament Select committee. Video is below + links to papers. Matters still moving fast and there’s uncertainty (though NF expresses reasonable confidence at times) but as of 25 March, this provides a base case scenario for England. This are my interpretations of the meeting, mistakes possible. Full video source is below. Full Transcipt available here.

-SAGE gives advice on science, does not set policy.

-On assessing true NHS capacity - especially for mechanical ventilation and ICU - was only available in early/mid March.

-Based on original capacity estimates, NHS would be overwhelmed 8x without suppression

-NHS has brought on new capacity as of mid March, but would still be overwhelmed 3x without suppression. NHS capacity estimates are rising.

-“Reluctant” conclusion that suppression only viable strategy. Reluctant because of huge economic damage. 

-UK examined many strategies. (A few other counties did too, but UK comprehensively looked at many strategies).

-“Reasonably Confident” that with current strategies + recent surge in NHS capacity then NHS  ICUs will have enough capacity nationally. It may get close on local level. (BY, I had the sense it might get very close on local levels from the tone of his response. Increase NHS capacity from eg “Nightingale” hospitals being built in a few days in several places eg London ExCeL Centre).

-On why we could not follow a South Korea “Contact + trace” strategy:

-Very clear that England did not have testing capacity in Feb to do this

-South Korea also has distancing and other strategies not only testing

-Very clear mass testing is very important going forward

-Peak infections in London - many variations locally -  likely to be 5 - 10%.

-Current England strategy = fewer than 20K Deaths (vs no supression strategy or no strategy = 500K deaths)

-Peak ICU demand likely in 2.5 to 3 weeks (from 25 March)

-Suggestion that in 3 to 4 weeks, a shift in strategy will be needed. Implication that this shift will need mass testing.

-There is an impact on health from economic damage. This work was mostly weighting the strategies needed to keep the NHS from being overwhelmed

-Summer may have an impact on virus transmission. NF suggests this may only be in the 10% to 20% range based on other viruses. Expressed uncertainty here.

-Reproduction rate “What we can see though in Europe in the last week or two is a rate of growth of the epidemic which was faster than the expected from early days in China. And so we are revising upwards our central best estimate of the reproduction. To something more a little bit about of the order of 3 or a little bit above rather than about 2.5 levels”

-“Adds more evidence to support the more intensive social distances measures applied this week because of the the higher the reproduction number…But the current value is still within the wide range of values modelled previously”

-Suggestion that vaccine or similar or transition first (BY: a testing + tracing? is an exit strategy as suppression not sustainable long term. (BY: That’s why my idea focuses on vaccine speed).

NF is suffering from COVID himself. Tyler Cowen awarded his group one of the first prizes from his awards on solutions to COVID-19 (Emergent Ventures). I believe the committee was focused on England as opposed to the whole UK.

The whole set of papers from SAGE can be found here and his video evidence plus more evidence is in the video below. SAGE =Scientific Advisory Group for Emergencies.

The Imperial College papers are here. The link to the video is here on Parliament TV.

My thought on speeding the pathways on regulatory approval for vaccines.


There are a set of valid criticisms/queries on (amongst many others):

-whether SAGE took enough evidence from Chinese scientists and others outside of UK

-why UK testing hasn’t scaled up faster (and involved those who do have testing capability)

-why preparedness was not better given . eg SARS-classic, and many thinkers (eg Bill Gates) forecasting the scenario we are now seeing.

But, IMO, there are misplaced criticisms on the Ferguson model and what it was suggesting. It was this model that convinced UK government to move to a supression strategy to keep from overwhelming the NHS. This has almost certainly saved thousands of lives and not overwhelmed the NHS albeit at an economic cost that also has second order negative impacts. (Note, a skeptical view can be found at Hector Drummond)

Full Transcipt available here.