COVID-19 by the numbers

Reviewed by Emily Henderson, B.Sc.Apr 2 2020

Numerical data sometimes reveal facts that are otherwise concealed within an onslaught of information from an overwhelming number of sources. Prof. Ron Milo and research student Yinon Bar-On of the Weizmann Institute of Science's Department of Plant and Environmental Sciences, together with American colleagues Prof. Rob Phillips of Caltech and Dr. Avi Flamholz of the University of California, Berkeley, have now employed an original research method to organize the flood of coronavirus information in an orderly framework.

The scientists examined hundreds of studies from around the world. The first stage of the project required the scientists to understand the different measurement and estimation methods so that they could coordinate and translate all the findings into the same "language" – a complex task requiring great care. The scientists' experience helped them in this task, as they translated and consolidated a wealth of data and findings that they accumulated in previous studies: the number of cells in the human body, biomass distribution on Earth, and more. (For example, see: http://book.bionumbers.org/.)

The research was fast-tracked to publication in the journal eLife. One of the interesting findings highlighted by the collected data is the similarity between the coronavirus genome and the genome of other viruses. For example, the genome of the coronavirus is:

• 96% identical to a coronavirus genome that infects bats
• 91% identical to a coronavirus genome that infects scaly anteaters (pangolins)
• 80% identical to the SARS virus that erupted about two decades ago
• 55% identical to the MERS virus that erupted eight years ago
• 50% identical to the coronavirus that causes "common colds"

The scientists also present numerical data on the coronavirus's attachment to various organs in the body (bronchi, lungs, different types of cells, and more).

The study presents the number of copies and other quantitative features of virus "targets," which are relevant for developing vaccines and pharmaceuticals that block the virus's ability to adhere to and penetrate a human cell.

An additional part of the team's research relates to the virus's mutation accumulation rate. This value is related to the chance (risk) that the virus will bypass vaccines developed against it – and return to attack humans. The coronavirus's mutation accumulation rate is relatively slow compared to influenza viruses; Prof. Milo cautiously estimates that this may indicate that drugs and vaccines developed by scientists will be more durable in curbing this virus over time.