Article by Gavin Freeguard: “Covid-19 did not only dominate our lives in April 2020. It also dominated the list of new words entered into the Oxford English Dictionary.
Alongside Covid-19 itself (noun, “An acute respiratory illness in humans caused by a coronavirus”), the vocabulary of the virus included “self-quarantine”, “social distancing”, “infodemic”, “flatten the curve”, “personal protective equipment”, “elbow bump”, “WFH” and much else. But nestled among this pantheon of new pandemic words was a number, one that would shape our conversations, our politics, our lives for the next 18 months like no other: “Basic reproduction number (R0): The average number of cases of an infectious disease arising by transmission from a single infected individual, in a population that has not previously encountered the disease.”
![graphic](https://oup.silverchair-cdn.com/oup/backfile/Content_public/Journal/jrssig/21/1/10.1093_jrssig_qmae004/2/m_qmae004f1.jpeg?Expires=1709884371&Signature=09uURPu4GghslQCPg14OAigyT1uBrOlRiZOfoLDE9tGmbmtHsvOpQXYPtb-itQjTafUYNw3gZe4LNF2wPcVd4ai2nwS8DYw3bffurjOu5oZ9rz0fFsu27crZVMBPEfafoIWu~E3qZMiNy-CiIIzdTNlru3alZ0b0J1ag~3OhAR5RbTjiJnAjYLQ5VD0Z-CMTQnI6hb3i-jv12tj7BeOYblGTb8gE81eQXoqb0tOmx8hn35w2nJAT0pPiQNSR9QTd9617Pd~mHEVocydzCuC47YVBBO1lmzDtBu8JNgz50UpiuUixZIgEDW8-QbSD0WlIWhkK6H4wQ2HsrK5-6jR6jg__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
“There have been many important figures in this pandemic,” wrote The Times in January 2021, “but one has come to tower over the rest: the reproduction rate. The R number, as everyone calls it, has been used by the government to justify imposing and lifting lockdowns. Indeed while there are many important numbers — gross domestic product, parliamentary majorities, interest rates — few can compete right now with R” (tinyurl.com/v7j6cth9).
Descriptions of it at the start of the pandemic made R the star of the disaster movie reality we lived through. And it wasn’t just a breakout star of the UK’s coronavirus press conferences; in Germany, (then) Chancellor Angela Merkel made the most of her scientific background to explain the meaning of R and its consequences to the public (tinyurl.com/mva7urw5).
But for others, the “obsession” (Professor Linda Bauld, University of Edinburgh) with “the pandemic’s misunderstood metric” (Nature: tinyurl.com/y3sr6n6m) has been “a distraction”, an “unhelpful focus”; as the University of Edinburgh’s Professor Mark Woolhouse told one parliamentary select committee, “we’ve created a monster”.
How did this epidemiological number come to dominate our discourse? How useful is it? And where does it come from?…(More)”.