Why the R number is important to fight coronavirus
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Coronavirus R0: What is the R number and why does it matter?

In the daily briefing earlier this week, Prime Minister Boris Johnson said to avoid the "disaster" of a second peak the UK must keep the R rate below one.

But what is the R number and why does it matter?

BBC health correspondent Laura Foster explains what governments are aiming for and why it matters.

Video by Terry Saunders, Laura Foster and Tobias Chapple

  • 02 May 2020
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