Time, temp, an ph. I do not know the specifics on COVID, but longer time at lower temp will kill viruses and bacteria just fine. That is why sous vide cooking works
WASHINGTON STATE
Author: KING 5 Staff
Published: 1:51 PM PST March 1, 2020
Updated: 11:53 PM PST March 1, 2020
Excerpt:
The Kent School District announced late Sunday that Kentwood High School and Covington Elementary School would be closed Monday, March 2. A Kent family with connections to both schools has an adult family member with flu-like symptoms awaiting test results for coronavirus.
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In addition to those five schools, Lake Washington Institute of Technology will be closed on Monday and Tuesday for cleaning and disinfecting ***after a group of nursing students visited Life Care Center in Kirkland, where 50 people are being monitored. ***