ABSTRACT
Background: The risk of SARS-CoV-2 infection when people handle the linens used by coronavirus disease (COVID-19) patients is uncertain. We examined the risk of SARS-CoV-2 infection among workers who change and wash the linens contaminated by SARS-CoV-2.Methods: This was a randomized controlled trial. Participants at a hospital and an accommodation facility who tested positive for SARS-CoV-2 were registered from September 16 to November 19, 2020. One of five washing (water, detergent, or softener) and disinfection (80℃ 10 min or 250 ppm sodium hypochlorite) methods was assigned to each facility on each washing day (the day of admission (day 1) and day 3) using static simple randomization. Samples before and after washing/disinfection were tested for RT-PCR and virus isolation on day 1 and day 3. The air in the workspace and the personal protective equipment worn by linen-handling people were also tested on days 1, 3, 5 and 7.Findings: Among 700 samples from 13 COVID-19 participants and their surrounding environment, SARS-CoV-2 RNA was detected from 14% (52/362) of the linens used by COVID-19 patients (cycle threshold (Ct) value:33-40). After washing or disinfection, SARS-CoV-2 RNA was detected from samples washed by laundry detergent or fabric softener with high Ct values (>36). SARS-CoV-2 RNA was also detected with high Ct values (>36) from 10% of gowns from people who handled used linens (5/52) but not from goggles nor N95 masks, and from 15% of air samples in the rooms where linens were retrieved (16/104). No SARS-CoV-2 was isolated from any samples.Interpretation: The risk of SARS-CoV-2 infection in handling linens used by COVID-19 patients exists but seems to be low and the contaminated linens were safe after washing by laundry detergent.Funding: This study was supported by the grant from Ministry of Health, Labour and Welfare (Grant No. 20CA2036).Declaration of Interest: All authors declare that they have no conflict of interest.Ethical Approval: This study was approved by the Institutional Review Boards of the National Institute of Infectious Diseases Japan (approval No. 1167) and International University of Health and Welfare (approval No. 20-Nr-066).