How is using E. Coli for testing sterilization an accepted protocol? Viruses, even big ones like corona viruses, are much smaller than bacteria. Viruses are very very different than bacteria.They should have tested the sterilization procedure on a virus. Yes, it is harder but lives are at stake.

Escherichia coli is a rod-shaped bacterium. Each bacterium measures approximately 0.5 μm in width by 2 μm in length. Coronaviruses are large pleomorphic spherical particles with bulbous surface projections.[12] The diameter of the virus particles is around 120 nm.

There are 1000 nm in 1 um.