Table of contents

  1. Using this guide
  2. Clinically extremely vulnerable
  3. Coronavirus and COVID-19
  4. Coronavirus Job Retention Scheme
  5. Deaths and COVID-19
  6. Furlough
  7. Local lockdowns and restrictions
  8. Lockdown
  9. Long COVID
  10. New variants of the coronavirus
  11. NHS Test and Trace
  12. Outbreak or pandemic
  13. Pre-coronavirus and pre-lockdown
  14. Quarantine
  15. R number
  16. Self Employment Income Support Scheme Grants
  17. Self-isolation
  18. Shielding
  19. Social distancing
  20. Spread
  21. Support bubble
  22. Vaccines and vaccinations 
  23. Waves

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R number

R number refers to “reproduction number”, which is the average number of secondary infections produced by a single infected person.  

If R is greater than 1, the epidemic is growing.  

If R is less than 1, the epidemic is shrinking.  

If R is equal to 1, the total number of infections is stable.  

Use “reproduction number (R number)” and define it as “the average number of secondary infections produced by a single infected person” the first time you use it. You can refer to “R number” after that.  

Do not use:  

  • “R Number” with both capitalised  
  • “r number” with both lower case