Environmental Contamination of SARS-CoV-2 Delta VOC by COVID-19 Patients Staying in the Hospital for More Than Two Weeks

Background: Patients infected with SARS-CoV-2 Delta VOC have a longer course of disease. We detected the air, surfaces, and patient's personal items in the wards of the second hospital of Nanjing during the outbreak of the COVID-19 Delta Variant to identify the environmental contamination, which provides a theoretical basis for the prevention and control of COVID-19 variation beads in the future.Methods: In the cross-sectional study, we collected and analyzed clinical features, demographic and epidemiological data, laboratory and swab test results, and surface and air samples of 144 COVID-19 cases.Results: The time from symptom onset to surface sampling was 25 days (IQR, 21 to 33 days). Positive throat swabs were detected in 52(36.1%) patients, of which only 8(5.6%) patients had N or ORF1a/b genes Ct value <35 on the surface sampling day. Among the 692 environmental surface and air specimens collected from 144 COVID-19 cases, 3 specimens (3/692, 0.4%) related to 5 cases (3.5%, 5/144) were detected positive on RT-PCR. Overall, bedside tables (2/144, 1.4%) were most likely to be contaminated, followed by toilet seats (1/81, 1.2%).Conclusion: The environmental contamination by SARS-CoV-2 Delta VOC-infected cases with disease duration of more than two weeks is limited.