March 29, 2020 • Reading time 2 minutes
Published 30 March 2020
Yesterday the Telegraph published our estimations of how many people have the Covid-19 disease. We calculated that, as of Friday, there were 1.6 million people in England with the disease. Today Imperial has estimated a similar number. Both are high, but a long way off the potential and the pressure is substantial.
Testing has been a hot topic for a few weeks (do you think you may have had it?). But it takes time to build and develop the capacity, which unlike the exponential growth of infectious disease does not scale quite as quickly as many would like – the complex supply chain, access to reagent and the workforce challenges of who does the testing all being issues to solve.
Focusing tests on suspected patients in hospitals currently delivers the most value. When there is limited access to PPE, testing helps make sure it is only used when needed. This pattern of testing is visible in data on the rate of discovery (below).
Over 30% of people tested are now confirmed Covid-19 cases. The same number was less than 10% two weeks ago. While the spread of Covid-19 is exponential, the growth in testing is probably more…. quadratic (i.e. not quite as quick).
Once we get past the current Covid-19 peak in mid-April, a difficult question will be how and when we can return to normality (if that still exists). In China, they are still on lockdown across much of the country (i.e. a very controlled approach). The plan being suggested in the United States is worryingly relaxed (i.e. not a very controlled approach).
Probably the UK will try to find a third way – perhaps an intelligent NHSX App that can be linked to test results and provide contact tracing if an infection is found. One way to start this could be random testing (like in Iceland) to help understand and contain the spread of disease.