WSI’s TRUpath™ Process Relieves Laundries’ COVID-19 Concerns
As a result of the current pandemic, it has become increasingly important to understand how commercial wash formulas affect known amounts of viruses. Non-pathogenic surrogate viruses that display traits comparable to the pathogenic viruses are commonly used for testing. Surrogate viruses are used because they share similar physical structures to the pathogenic virus and display similar resistance to laundering conditions such as temperature, pH, detergency, mechanical action, and water exchanges.
The surrogate test virus is a non-enveloped virus which is more difficult to “kill”, and shares similarities with viruses that the U.S. Environmental Protection Agency (EPA) deems as surrogates for emerging viral pathogens, such as COVID-19. COVID-19, on the other hand, is an enveloped virus. Enveloped viruses, like COVID-19, are susceptible to many different environmental factors, which makes them easier to “kill.”
Log reduction is a measure of how thoroughly a process reduces the concentration of the virus. The EPA requires log 3 reduction for disinfectant products to be registered with viral claims.
| Log reduction | % reduction | CFU remaining |
| Log-0 | 0% | 10,000,000 |
| Log-1 | 90% | 1,000,000 |
| Log-2 | 99% | 100,000 |
| Log-3 | 99.9% | 10,000 |
| Log-4 | 99.99% | 1,000 |
| Log-5 | 99.999% | 100 |
| Log-6 | 99.9999% | 10 |
| Log-7 | 99.99999% | 1 |
The WSI TRUpath™ laundering process demonstrates a log 7 reduction of the surrogate test virus, which is a significantly greater reduction of the virus. A log 7 reduction results in a 99.99999% reduction of the viruses present on the fabric. As a result, WSI wash formulas are expected to be effective against COVID-19.