Latest estimates suggest the UK-wide reproduction rate of coronavirus – the so-called “R rate” – has remained at 0.7 to 1.0 for a second week.
Boris Johnson has said driving the R down is key to any further easing of the lockdown measures. There is a time lag in the calculations, with the government scientists’ latest R value relating to what was happening two to three weeks ago.
If R is greater than 1 the epidemic is generally seen to be growing; if R is less than 1 the epidemic is shrinking. R measures the number of people, on average, that each sick person will infect.
An R number of 1 means that on average every person who is infected will infect 1 other person, meaning the total number of new infections is stable.