A preprint came out yesterday entitled “Transmission Potential of SARS-CoV-2 in Viral Shedding Observed at the University of Nebraska Medical Center“. They looked at actual virus shed by patients in a healthcare setting (as opposed to artificial virus aerosols). They found widespread contamination of surfaces and objects in the room… but all of the detection was of viral RNA. They attempted to measure the viability of the virus but were unable to get any replication in tissue culture. Here’s the abstract:
Abstract: Lack of evidence on SARS-CoV-2 transmission dynamics has led to shifting isolation guidelines between airborne and droplet isolation precautions. During the initial isolation of 13 individuals confirmed positive with COVID-19 infection, air and surface samples were collected in eleven isolation rooms to examine viral shedding from isolated individuals. While all individuals were confirmed positive for SARS-CoV-2, symptoms and viral shedding to the 15 environment varied considerably. Many commonly used items, toilet facilities, and air samples had evidence of viral contamination, indicating that SARS-CoV-2 is shed to the environment as expired particles, during toileting, and through contact with fomites. Disease spread through both direct (droplet and person-to-person) as well as indirect contact (contaminated objects and airborne transmission) are indicated, supporting the use of airborne isolation precautions.
While this seems like good work, I take issue with the last line. There’s nothing in this data that supports the statement that disease can be spread through indirect contact. It’s of course certainly possible, but not shown here.