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The Vital Number We Need To Know To Beat COVID
Death rates. Case rates. Case rates in proportion to testing. Recoveries. Hospitalizations.
The numbers of the COVID-19 epidemic are stark. At the time of writing the US has recorded over 1.2 million confirmed cases, with the true number likely higher, and a bit over 72,000 deaths.
People under lockdown are watching for case counts per day to start falling.
We’re all paying so much attention to numbers, but there’s one which isn’t getting enough attention.
That number is the R0.
What is R0?
R0 (R naught) is a mathematical term that’s used to gauge the contagiousness of an infection.
A disease’s R0 is the average number of people any given patient infects. It’s short for basic reproduction number, and assumes that all individuals in the population are susceptible to infection.
R0 is calculated by epidemiologists, and it’s not generally measured directly, but rather through models. Discussing it, therefore, comes with some caveats.
However, it’s still a vital number.