Do the experts believe in the R number?

The R-number has been declared the most important metric in monitoring Covid in Britain. For young children to return to school in June, or for pubs to open in July, it is always linked to the rate of Covid transmissions – the R-number – staying below one. Above one is the danger zone: it means each infected person is infecting, on average, more than one other. So plans to liberalise are put on hold and we possibly enter a more severe lockdown once again. When explaining his strategy last weekend, the Prime Minister even showed a picture of an R-Number speedometer. But it gave no reading. We’re instead told a range: is that it hovers somewhere between 0.7 and 1. But we have never been told exactly what the R-number is.

In today’s press conference, Deputy Chief Medical Officer Dr Jenny Harries gave an honest assessment of the R-number’s limitations. She didn’t sound very convinced of the idea that the UK – as a country – has a R-reading.