< Virus

SARS-CoV-2 and COVID-19, what's that? Some figures

Text updated on 2020-04-21

COVID-19 is a disease caused by the SARS-CoV-2 coronavirus.

The first cases were reported in November 2019 in the city of Wuhan, Central China. After that initial report, the virus spread around the world.

Virus diameter: 1E-7 meters, 10,000 times smaller than a mustard seed.

Volume: 1E-18 liters, 50,000 billion times smaller than a drop of water

Mass: 1E-15 grams, 350 million times lighter than a very fine grain of sand

Time: Ten minutes to enter a cell and 10 hours to release small virions, 1,000 virions per cell.

Maximum quantity of virus measured by RNA tests on samples :

Nasopharyngeal: 1 billion per milliliter (high), throat: 10,000 per milliliter, stool: 100 million per gram of stool, sputum: 100 billion per milliliter.

facebook twitter linkedin


Bar-On, Y. M., Flamholz, A., Phillips, R., & Milo, R. (2020). SARS-CoV-2 (COVID-19) by the numbers. Elife, 9, e57309.

Tests based on the amount of virus present in saliva.

Azzi, L., Carcano, G., Gianfagna, F., Grossi, P., Dalla Gasperina, D., Genoni, A., ... & Maurino, V. (2020). Saliva is a reliable tool to detect SARS-CoV-2. Journal of Infection.

Further reading

What do the abbreviations COVID, SARS, CoV, RNA, etc. mean?

Why put on a mask?

How do you wash your hands?