What does "....10000 units per 15 min (quick reduction)" mean?

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mesa
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Hello, looking to find out what the term "10000 units per 15 min (quick reduction)" from the WHO means in terms of using heat to kill a virus.
 
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mesa said:
Sure thing:

https://www.who.int/csr/sars/survival_2003_05_04/en/

Thanks. Later in the document, they clarify that the amount refers to "10 000 infectious virus units in 15 min." So basically, they had a solution of the virus containing 10,000 infectious viruses, heated it at 56°C for 15 min, and found no infectious viruses remaining after heat treatment (meaning the heat had inactivated all of the viruses in solution).

One can measure the number of infectious viruses in a solution by applying that solution to a plate of cultured cells, and measuring the number of cells that become infected (a process called viral titering).
 
I would tend to think that the 10000 units refers to a plotting of before and after on a logarithmic scale, base 10, since if the studies are dealing with a large number of items ( viruses in this case ) before the application of the treatment to the much smaller number if items after the treatment.
In other words a 10000 unit reduction is a 104 reduction of the items in the original sample.