Saturday, June 25

# Coronavirus: all the SARS-CoV-2 in the world could fit in a soda can (and how that mathematical conclusion was reached)

• Christian Yates*
• The Conversation

When asked to estimate the total volume of SARS-CoV-2 in the world for the BBC’s More or Less program on Radio 4, I will admit that I had no idea what the answer would be. My wife suggested it would be the size of a lap pool. “That or a teaspoon,” he said. “Usually it’s one or the other with these kinds of questions.”

So how do you begin to calculate what the total volume really is? Fortunately, I am used to making these types of estimates, having carried out several of them for my book “The mathematics of life and death.”

However, before embarking on this particular numerical journey, I must make it clear that this is a approximation based on the most reasonable assumptions, but I’ll happily admit that there may be room for improvement.

So where do you start? It is best if we first calculate how many SARS-CoV-2 particles there are in the world. For this, we will need to know how many people are infected. (We will assume that humans, rather than animals, are the most important reservoir for the virus.)

www.bbc.com