Environmental contamination by SARS-CoV-2 Omicron variant in a designated COVID -19 treatment hospital

Abstract:

Objective To evaluate the contamination of public environment and medical staff's personal protective equipment (PPE) by SARS-CoV-2 Omicron variant. Methods Public area, PPE removal area and PPE of a designated COVID -19 treatment hospital were sampled. Real time fluorescence quantitative polymerase chain reaction was adopted to detect SARS-CoV-2 nucleic acid and Ct value was reported. Factors related to positive SARS-CoV-2 nucleic acid results of PPE were analyzed. Results A total of 100 environmental specimens from ward public area were collected and the overall positive rate was 30.00%. Positive rates of elevator floor in PPE removal area (60.00%), corridor public area floor (60.00%), and the elevator button in PPE removal area (40.00%) were the highest. SARS-CoV-2 nucleic acid detection rates in the first-level and second-level PPE removal areas were 18.33% and 1.67%. SARS-CoV-2 nucleic acid was detected from 48.33% staff's PPE, 35.00%, 21.67% and 8.33% of which were detected from soles of outer shoe covers, outer gloves and protective clothing. Univariate analysis showed that PPE of doctors and medical staff performing high-risk manipulation had high positive rate of nucleic acid (all P < 0.05). Conclusion Omicron variant contaminated the ward public area, the first-level PPE removal area and PPE to different degrees. Personal protection as well as regular environmental cleaning and disinfection can reduce the infection risk of medical staff.