How many SARS-CoV-2 viruses are in circulation at the moment? And what is their total mass?

To clarify: if there are 10 000 viruses on average in an infected human and 100 000 humans are infected the answer would be (if all viruses are in humans, which probably isn't true) 10^4 x 10^5 = 10^9 viruses.

Of course I am only looking for a rough estimate, a number that, when multiplied with 10 or 0,1 (so two magnitudes) or so, is correct.

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1 Answer 1


Based on all species of viruses, Everyday you breathe in 100 million viruses. There can be 1mn+ viruses per ml of blood of patients. Covid-19 diameter = 125 nm.

Perhaps it's wrong, the maths would go something like this:

1mn * 1000ml * 5liters * 400k patients = 2^12 - 2^13 sars2 viruses.

total volume of viruses = 2^13 viruses / 1^15 viruses per cm3 = 0.02 cm3

(10^7 nanometers per centimeter, 125nm diameter, gives, about 10^(5*3) viruses per cm3.)

Weight of all the Covid Sars 2 in the human population = a raindrop or a teaspoon of hydrocarbons/mayonnaise, probably less than a teacup.

Perhaps i am wrong, it's reasonable to think that the people with major symptoms contain about 1 ml of virus. 20k x 1ml = 20cm3


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